# Model of a Bessemer Hot Tube Oil Field Engine



## cfellows (Sep 10, 2012)

I've been thinking about this for some time now and have done a few preliminary drawings.  So, I think my next engine project will be a somewhat stylized model of a Bessemer 2 stroke oil field engine.  I want to get it as close to the real deal as I can without using any castings.

At this point I'm planning on a 1.25" x 1.75" bore and stroke.  The flywheel(s) will be a little under 9" diameter and the cylinder will be made from a piece of DOM tubing, 4" long x 2" diameter.  It will be water cooled and I want to try to make it fired with a hot tube. 

If I can make this work, it will be a pretty simple engine to build.  There won't be any gears, no valves, and no ignition, although I may have to fall back on an ignition system if I can't get the hot tube to work.  It should also be an easier hot tube engine to make since it won't require an injector or injector pump.  I plan to use a vapor fuel tank so I won't need a carburetor.

Here is a video of the engine that is my inspiration:

[ame]http://www.youtube.com/watch?v=_9QbtZNOKX0&feature=autoplay&list=ULiY3F-KIcuws&playnext=1[/ame]

This model was designed by John Burns and the castings are supposedly still sold by Robert Horner although I was never able to reach the latter.  I did reach John Burns and he gave me a little bit of information about his design, but he no longer has any financial interest in the plans or castings.  At any rate, I believe the Burns model is larger than I want to build and the castings are probably priced at a great deal more than I would want to spend.  Besides, designing them is half the fun! 

I hope to start making chips in the next few days although a 10 day vacation scheduled for the end of the month will probably delay much progress on the engine.

Chuck


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## hitnmiss49 (Sep 10, 2012)

Chuck,

The construction of that model was published in Modeltec Magazine in about 1980 to 1982. I'm not sure what the number of the issues were but if you can locate them it would probably be a big help. Modeltec is no longer in publication but I am sure there are many people out there with the copies you need.

I have an original 22 1/2 hp Bessemer that I could send you pics of any part of the engine that might help you.

I will be following this project closely as I have wanted to build one like this for a long time.

Lonnie


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## Brian Rupnow (Sep 10, 2012)

Chuck--I've never heard of this engine, but knowing your track record I'm sure that what you create will certainly be interesting. Good luck, I'll be following.---Brian


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## cfellows (Sep 10, 2012)

hitnmiss49 said:


> Chuck,
> 
> The construction of that model was published in Modeltec Magazine in about 1980 to 1982. I'm not sure what the number of the issues were but if you can locate them it would probably be a big help. Modeltec is no longer in publication but I am sure there are many people out there with the copies you need.
> 
> ...


 
Thanks Lonnie.  Following your lead, I did some research and found a PDF index of Modeltec on Google:

http://www.discoverlivesteam.com/magazine/MODELTEC INDEX.pdf

Couldn't find anything on the Bessemer but there are a series of references to an Oil Field Pumping Engine starting in 1994 and running into 1995.  Do you know anything about that series of articles?

Chuck


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## kuhncw (Sep 10, 2012)

Chuck, I believe the ModelTec article covered a Reid engine.  This is the engine with the power cylinder and a smaller cylinder in tandem that pumped air into the power cylinder.  

Regards,

Chuck Kuhn


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## Ed T (Sep 10, 2012)

If I recall the hot tube is an externally heated "pipe" that runs into the combustion chamber and helps to initiate what is basically compression ignition. Very much like the glo plug on a model airplane engine. I would be concerned that the thermodynamics of such a device might not scale too well. Don't know for sure, just a hunch. If that's the case, I'd make provision for some kind of more conventional ignition or, at least, don't design into a corner that makes it very hard to do.


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## mhirst121 (Sep 10, 2012)

Hello Chuck, that will make a nice looking model. The hot tube is not a problem on a model, they work just as well as the full size engine once you get the correct size hole down the tube. For others that may not know you move the burner either closer or further away from the cylinder to move the `hot spot` to alter your ignition timing. The model I am currently on with is gas fuelled and hot tube ignition. In the past I have converted all manner of small power engines to run on hot tube ignition, villiers, briggs and lister d`s to name a few.
The Reid engine runs on the Clerk cycle, an early type of two stroke that had two cylinders, one for charging and one for combustion, these models also run well on hot tube ignition.

Cheers,
MartinH


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## hitnmiss49 (Sep 10, 2012)

Chuck,

The series on building the Oil Field Pumping Engine is I believe the correct one that detailed the building of John Burns Model Bessemer. I think I have the issue with the final article in the series if I can find it. I think he did not refer to it as a Bessemer because he did not have the rights to that name which belong to Cooper-Bessemer. He does own the rights to the Reid name.

I don't remember there being a build article in Modeltec for the Reid Model but I never saw all the Magazines so it is possible. That was a very good magazine. It was a shame they went bankrupt.

If I can be any help with pics or measurements from my 22 1/2 hp Bessemer don't hesitate to contact me on here or with a PM.

Lonnie


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## cfellows (Sep 11, 2012)

mhirst121 said:


> Hello Chuck, that will make a nice looking model. The hot tube is not a problem on a model, they work just as well as the full size engine once you get the correct size hole down the tube. For others that may not know you move the burner either closer or further away from the cylinder to move the `hot spot` to alter your ignition timing. The model I am currently on with is gas fuelled and hot tube ignition. In the past I have converted all manner of small power engines to run on hot tube ignition, villiers, briggs and lister d`s to name a few.
> The Reid engine runs on the Clerk cycle, an early type of two stroke that had two cylinders, one for charging and one for combustion, these models also run well on hot tube ignition.
> 
> Cheers,
> MartinH



Thanks, Martin, I'd sure be interested in seeing any pictures or drawings you might have of one of your hot tubes.  If I understand them correctly, the tube doesn't actually extend into the cylinder... rather they extend outward from the cylinder and the fuel mixture is forced out into the tube until it reaches the hot spot whereupon it ignites.



hitnmiss49 said:


> The series on building the Oil Field Pumping Engine is I believe the correct one that detailed the building of John Burns Model Bessemer. I think I have the issue with the final article in the series if I can find it. I think he did not refer to it as a Bessemer because he did not have the rights to that name which belong to Cooper-Bessemer. He does own the rights to the Reid name.
> 
> I don't remember there being a build article in Modeltec for the Reid Model but I never saw all the Magazines so it is possible. That was a very good magazine. It was a shame they went bankrupt.
> 
> ...



Thanks for the offer Lonnie.  I will take you up on that if need be.  I know the pistons on these engines needs to be at least as long as the stroke.  I'm assuming they must be hollow rather than solid.  Are they sealed on both ends?

Chuck


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## hitnmiss49 (Sep 11, 2012)

Chuck,

I do not think the piston would need to be hollow on a model. Jan Ridder's Simple 2 Stroke operates on the same principle as the Bessemer and it has a solid piston. He does however have an expansion chamber outside the cylinder so perhaps that could be the benefit of a hollow piston. I always assumed it was to reduce the mass of the piston to help balance the engine.

Lonnie


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## hitnmiss49 (Sep 11, 2012)

Chuck,

I did a couple quick measurements this morning on my 22 1/2 HP Bessemer. I already had it partially disassembled so it was pretty easy to get these measurements.

Bore 10"
Stroke 15"
Piston 10" x 16"
Cylinder is just over 31" deep  12" from the head end of the cylinder to the ports. The piston goes 1/8" past the ports on the return stroke.
Flywheels 4" Wide x 68" Diameter

As you can probably see from these measurements the piston almost touches the back of the cylinder on the return stroke and the deflectors on the front of the piston goes a little ways into the head on the compression stroke.

Hopes this helps you in designing your model.

Lonnie


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## Kaleb (Sep 11, 2012)

Would you be able to upload some plans down the track? This sounds like a good project to make on my 9" Hercus.


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## cfellows (Sep 11, 2012)

hitnmiss49 said:


> Chuck,
> 
> I did a couple quick measurements this morning on my 22 1/2 HP Bessemer. I already had it partially disassembled so it was pretty easy to get these measurements.
> 
> ...


 
Thanks, Lonnie, it looks like I've got my dimension ratios about right.  

Chuck


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## cfellows (Sep 11, 2012)

Kaleb said:


> Would you be able to upload some plans down the track? This sounds like a good project to make on my 9" Hercus.


 
Yes, this should be a pretty simple engine, so I will make some drawings available.

Chuck


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## Lance (Sep 11, 2012)

Chuck, you have my utmost attention. My great uncle had a lease with a besssemer he pumped until he was in late eighties. I was stunned one year I went to visit and he had drug the bessemer out and replaced it with a chrysler 318, told me it easier to start.. He pumped with the 318 and coon hunted well into his ninteys. I would love to have a model of a Bessemer.
Lance


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## cfellows (Sep 12, 2012)

OK, I guess this is officially a work in progess at this point.  I broke ground on the piece that will become the front or cylinder end of the frame.  I started out with a chunk of 2" x 3" x 3/8" angle iron 2 3/4" wide.  The engine frame could just as easily be made out of cold rolled flat steel, but I want the finished engine to look at least a little bit like it was made from castings.  







After squaring the sides and machinging the piece to length, I cut off the excess on the 2" leg of the angle iron.  






See, it's starting to look like a casting already, huh?  The two ends of the piece will line up with the sides of the frame, so the edges need to match the profile of the frame sides at the bottom.  The first step is to use a 3/8" end mill and plunge cut the radius near the base, making multiple plunges taking about .020" each time.











Next I used my metal cutting bandsaw to cut off the excess above the plunge cuts, then mounted the piece in my milling vice and used an end mill to bring the edges down to the final size.  This is what it looks like after I finished milling it to width.






Now to get the top part cut to the proper shape.  First I cut the corners off with my bandsaw






Then finished off the radius shaping using my rotary table and an end mill.  This took some time since I could only cut about .020" each pass.











Next will be the frame sides...

Chuck


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## cfellows (Sep 12, 2012)

By the way, here's a drawing of what I'm aiming for with the engine frame.






Chuck


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## hitnmiss49 (Sep 12, 2012)

Chuck,

That is a great start you have there. I can't wait to see a video of it running. 
What size do you plan on making the Flywheels?

Lonnie


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## cfellows (Sep 12, 2012)

hitnmiss49 said:


> Chuck,
> 
> That is a great start you have there. I can't wait to see a video of it running.
> What size do you plan on making the Flywheels?
> ...


 
Thanks, Lonnie.  The flywheels I have are a little under 9" diameter and weigh about 5 lbs each after machining.  I have 2 of them, but will only use 1 if the engine runs like I want with just 1.

Chuck


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## hitnmiss49 (Sep 12, 2012)

Chuck,

I think it will probably run fine with one flywheel. There were a lot of engines around this part of the country that were steam engines originally. They would drill the well with the steam engine then fit it with a gas cylinder later. They are commonly referred to as half-breeds. Most of them had one flywheel but many had an extra ring attached to the flywheel to make it heavier.

Lonnie


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## cfellows (Sep 12, 2012)

I finished cutting out the sides.  Still have a fair amount of shaping and finishing to do on them, but thought I'd post a couple of mock-up pictures to show the group kind of how it's going to look.












The cylinder, as shown, is the finished length and diameter, although it will need to be carved out and a water jacket added.  The flywheel is also the finished size.

Chuck


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## ProdEng (Sep 13, 2012)

Great idea using the radius in the angle iron; filed away for future reference


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## Jasonb (Sep 13, 2012)

Chuck please tell me you are not going to go to all the trouble of making it look like a cast engine and then use socket head screws as per your drawing 

J


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## cfellows (Sep 13, 2012)

Jasonb said:


> Chuck please tell me you are not going to go to all the trouble of making it look like a cast engine and then use socket head screws as per your drawing
> 
> J


 
Well, you know, can't make it look too much like a cast engine.  Wouldn't want to be accused of counterfitting!


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## cfellows (Sep 13, 2012)

Thanks, folks, the words of encouragement.  I got the engine frame mostly finished up today.  






After squaring and sizing the ends and milling all the bandsaw cuts on the bottom sides, I clamped the pieces in my milling vice and plunge cut the radiuses at each end of the cutout with a 3/4" end mill.  You can also see where I began cutting out the waste with my 4 x 6 bandsaw.

Here it is after both pieces have the waste cut out with the bandsaw.






Here I've cleaned up the cuttouts with an end mill, made the bottom piece, drilled and tapped the holes and bolted both side pieces to the bottom piece.  





















Still have to attach the front piece to the side pieces with SHCS's (sorry Jason) but I ran out of steam for the day.  More tomorrow.

Chuck


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## cfellows (Sep 14, 2012)

hitnmiss49 said:


> Chuck,
> 
> I did a couple quick measurements this morning on my 22 1/2 HP Bessemer. I already had it partially disassembled so it was pretty easy to get these measurements.
> 
> ...



Lonnie, what is the diameter of the piston rod where it comes out of the back of the cylinder?  Trying to get an idea of what mine needs to be.

Thx...
Chuck


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## Jasonb (Sep 14, 2012)

cfellows said:


> Still have to attach the front piece to the side pieces with SHCS's (sorry Jason)
> Chuck


 
Thats fine, I assume they will be counter bored and then filled with JB Weld or similar

J


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## hitnmiss49 (Sep 14, 2012)

cfellows said:


> Lonnie, what is the diameter of the piston rod where it comes out of the back of the cylinder?  Trying to get an idea of what mine needs to be.
> 
> Thx...
> Chuck



  Chuck, that rod is 1.625" diameter. 

Lonnie


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## hitnmiss49 (Sep 14, 2012)

Chuck,

 Here is is pic of a Pattin Bros Oilfield Engine. It looks almost identical to the model you are building. There are a few differences between it and the Bessemer, mainly the intake valve being on top. the exhaust on the side and the hot tube on the front of the head instead of on top. It also has a longer bedplate. 
The Pattin Bros were built in Marietta, OH. They are harder to find because there were not nearly so many built.
This is not my pic so I give credit to the person that generously posted in on the internet.

Lonnie


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## cfellows (Sep 14, 2012)

Thanks, Lonnie.  Although I'm calling this engine a bessemer, it's going to be pretty highly stylized and would probably more properly be called a generic half breed oil field engine.  I like the idea of having the hot tube coming out of the front of the head as it makes heating it a lot simpler.  

I plan to make my piston rod 1/4" diameter which would make it exactly 1/5 the diameter of the piston.  That's a little bigger, ratio-wise, than your bessemer so I think it will be strong enough.

Chuck


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## cfellows (Sep 14, 2012)

Here is a drawing of my plan for the cylinder assembly (minus the hot tube...).






I'm planning on only having coolant around the top part of the cylinder as shown to prevent having to seal around the intake and exhaust ports.  I also don't plan to have any coolant flowing through the head, again, to simplify things.  Assuming I don't run the engine very fast or hard or for long periods of time, does anyone think I'll have a problem with the engine overheating?

Thx...
Chuck


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## hitnmiss49 (Sep 14, 2012)

cfellows said:


> Here is a drawing of my plan for the cylinder assembly (minus the hot tube...).
> 
> 
> 
> ...



Chuck, what program are you using to do these drawings?

Thanks, Lonnie


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## cfellows (Sep 15, 2012)

I use Visio.  Doesn't do 3d but does a decent job of 2d with 3d shading.  I've tried them all and this one meets my needs the best.

Chuck


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## Brian Rupnow (Sep 15, 2012)

Chuck--You are doing just marvelous with this build. Cool looking drawings too.


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## cfellows (Sep 15, 2012)

Thanks, Brian.

Sometimes in a small shop you have to be resourceful.  I needed to tap some 8-32 holes in the end of the engine frame which is 10.25" long.  So here's a picture of how I did it.






These pictures are probably a bit of old news since I already posted mock-up pictures.  But, in these pictures, everything, except the flywheel, is fastened together.
















Chuck


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## cfellows (Sep 17, 2012)

Got started on the crankshaft today.  Started out with a piece of 1.5" x 5/8" cold rolled steel 5.5" long.  After measuring and laying out, I made cut lines along the length of each side of the shaft, then drilled and bandsawed out the opening between the webs.  All this was done to relieve stresses in the metal before laying out the center holes on each end which will be used to turn the shaft between centers.






Here I have the piece mounted between centers ready to turn the connecting rod journal.  I added a driving dog after this picture was taken.






In this picture I've finished turning the connecting rod journal.






Next I need to cut away the waste on both ends to start turning the outer ends of the crankshaft...






Uh oh... That doesn't look right... Crap!

OK, a nap and 3 hours later, I've started a second crankshaft crankshaft.  This time I managed to cut off the right pieces 






Maybe I can get this piece finished without screwing it up.

Chuck


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## cfellows (Sep 17, 2012)

OK, got the crankshaft pretty well finished.











Got the dimensions all pretty much right on, which actually surprised me... 

Chuck


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## Brian Rupnow (Sep 18, 2012)

At this rate you'll have that engine going before I get the Atkinson going!!!


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## cfellows (Sep 18, 2012)

Brian Rupnow said:


> At this rate you'll have that engine going before I get the Atkinson going!!!


 
Thanks for the vote of confidence, Brian, but I'm leaving for a 10 day vacation on the end of this week, so you get a little more time to get your engine running... .

And, the hard parts on my engine are still to be done.  So I'm guessing it'll be the end of October before I get this beast going.

Chuck


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## cfellows (Oct 4, 2012)

Back from vacation late Monday, a day to rest up from a day of flying and today I got back into the shop.  I finally settled on the design for the crankshaft bearings and caps, so today I finished up the caps and bored and reamed the 3/4" holes for the bearings.  











The bearings will be turned from either bronze or cast iron, although I'm leaning toward the latter and will be spool shaped with a flange on either side.  By the way, I discovered something about angle iron I didn't know before.  The pieces I used for the frame came from 3/8" thick 2" x 3" angle.  I found out today that one of the sides is thicker then the other.  One side measured about .350 and the other was .390.   As a result, the frame on one side of my engine is about .050" thicker than the other.  Luckily, it's not really noticable.  I made the caps for each side from cut-off's of the frame sides, so the caps each match the thickness of their respective frame.  

Next I'll probably make the bearings.  I'm a little reluctant to do any more work on the cylinder until I get a better feel for what I need to do.

Chuck


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## skyline1 (Oct 4, 2012)

Keep leaning mate, I'm a great fan of cast iron bearings. Gus and I had a discussion about them a couple of weeks ago and they are more common than you might think. They are superb for high speed stuff. (Bronze can do some very strange things at high speeds) and they run silky smooth especially on Silver steel shafts (Drill Rod).

Regards Mark


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## cfellows (Oct 4, 2012)

skyline1 said:


> Keep leaning mate, I'm a great fan of cast iron bearings. Gus and I had a discussion about them a couple of weeks ago and they are more common than you might think. They are superb for high speed stuff. (Bronze can do some very strange things at high speeds) and they run silky smooth especially on Silver steel shafts (Drill Rod).
> 
> Regards Mark


 
Thanks, Mark.  My sense is that cast iron bearings would be more forgiving if I fail to oil them as often as I should.  I'm hoping this will be a slow running engine and the cast iron should wear pretty well.

Chuck


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## cfellows (Oct 4, 2012)

Got a few more hours into day and made the crankshaft bearings.
The bearings are still a little tight, but they will loosen up with a little running in.  Also, I'm beginning to wonder if that flywheel isn't a little too big???












Chuck


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## kf2qd (Oct 4, 2012)

Actually - water jacket of some sort on the head would be more effective as the head takes most of the heat from compression and ignition. Similar to RC Nitro boats.  A cooling coil around the head and they don't worry about the cylinder.


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## skyline1 (Oct 5, 2012)

Hi Chuck

I see you went for Cast Iron. I expect you had black hands machining them. That's the free graphite in the iron. It makes them at least partially self lubricating and they do have a long life. I have used C.I. in turbines and they can outlive ball races even thundering round at 30,000 R.P.M. or more.

Cast Iron is also good for the big ends in wobblers they get a hard life because of the side thrust on the conrod. Bronze tends to go oval fairly quickly.

Don't worry about them being a little tight they always are when new (or they should be) cast iron glazes in and forms a tough surface layer. I was told by an engineer from McLaren  that it actually changes metallurgically in doing so and they were experimenting with it in full size racing engines. But I'm not a metallurgist so I couldn't guarantee that. Whatever the actual Physics and Metallurgy Cast Iron does make a great bearing material. 

I am amazed at how fast this engine is coming together keep up the good work.

Regards Mark


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## cfellows (Oct 5, 2012)

kf2qd said:


> Actually - water jacket of some sort on the head would be more effective as the head takes most of the heat from compression and ignition. Similar to RC Nitro boats.  A cooling coil around the head and they don't worry about the cylinder.


 
Hmm, interesting concept.  I hadn't really thought about just cooling the head.  I'll have to think about that...

Chuck


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## cfellows (Oct 5, 2012)

skyline1 said:


> Hi Chuck
> 
> I see you went for Cast Iron. I expect you had black hands machining them. That's the free graphite in the iron. It makes them at least partially self lubricating and they do have a long life. I have used C.I. in turbines and they can outlive ball races even thundering round at 30,000 R.P.M. or more.
> 
> ...


 
Thanks, Mark.  I've decided to stick with cast iron as much as possible.  I've considered using aluminum for the piston to minimize vibration, but am thinking I can probably get and keep a better fit if I use cast iron.  I don't want to use rings because of interference with the intake and exhaust ports, so a very close fit will be essential.  I wanted to use o-rings, but would have to round over and polish the edges ot the ports to keep from shredding the o-rings.

Chuck


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## Jasonb (Oct 5, 2012)

One of the problems with just water cooling the head on this engine unlike a Nitro Marine engine is that you won't get the force of the boat moving through the water to make the cooling water flow around the head, you really would need to add a pump a bit like the IHC vertical screen cooled that I made.

Also a water jacket will be better suited to the thermal movement that these type of engines rely on to make the water flow plus there is the fact its very slow reving and not encased in a hull like a glow engine so won't run anywhere near as hot.

J


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## skyline1 (Oct 6, 2012)

Hi Chuck

As you say aluminium would be lighter and as there is less mass being hurled up and down the cylinder every stroke it would tend to reduce vibration.

But to maintain good compression without rings to take up the slack as it were you would need a very close fitting piston. I think the problem would be that the thermal expansion of aluminium is much higher than that of the cylinder and could cause trouble as the engine got hotter at these close tolerances.

Cast Iron has an expansion closer to that of the cylinder so will be less trouble in this respect but it is heavier, a hollow piston could help something like an automobile piston perhaps.

Even if you don't use rings you could put oil retaining grooves on the piston.

Regards Mark


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## Goldflash (Oct 7, 2012)

Hi Chuck. This type of 2 stroke design fascinates me and I have been doing some preliminary sketches of something similar that I want to make but using a stepped piston to increase the volumetric efficiency. My main problem is that I see that for the pump side of the Piston / Cylinder I need to use some form of automatic valves for both the Inlet and outlet. I am looking at either spring loaded poppet valves or reed valves. What sort of valves are you intending to use. 
Another allternative maybe to have slide or piston  valves operated by eccentrics .
Regards Ralph


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## cfellows (Oct 7, 2012)

Goldflash said:


> Hi Chuck. This type of 2 stroke design fascinates me and I have been doing some preliminary sketches of something similar that I want to make but using a stepped piston to increase the volumetric efficiency. My main problem is that I see that for the pump side of the Piston / Cylinder I need to use some form of automatic valves for both the Inlet and outlet. I am looking at either spring loaded poppet valves or reed valves. What sort of valves are you intending to use.
> Another allternative maybe to have slide or piston  valves operated by eccentrics .
> Regards Ralph


 
I'm currently planning to use spring loaded ball check valves.

Chuck


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## Brian Rupnow (Oct 7, 2012)

Chuck---Can you please direct me to a link that describes the operation of this engine. I did a bit of a search and found that "Half breed" conversions were popular for converting steam engines to run on natural gas, and that hot tubes were more reliable than the (at that time) young sparkplug and battery technology. I learned about "barkers" being installed on the exhaust so that an oilman could tell by the distinctive sound of each engine if all the engines in an oilfield were running. However, I didn't find much about the actual operating theory of the engines. I have never seen an engine like that, and would like to know more about them.----Brian


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## cfellows (Oct 8, 2012)

Brian Rupnow said:


> Chuck---Can you please direct me to a link that describes the operation of this engine. I did a bit of a search and found that "Half breed" conversions were popular for converting steam engines to run on natural gas, and that hot tubes were more reliable than the (at that time) young sparkplug and battery technology. I learned about "barkers" being installed on the exhaust so that an oilman could tell by the distinctive sound of each engine if all the engines in an oilfield were running. However, I didn't find much about the actual operating theory of the engines. I have never seen an engine like that, and would like to know more about them.----Brian


 
A halfbreed engine is basically just a 2-stroke gasoline engine.  Have a look at Jan Ridders page for a pretty good explanation, on a smaller scale.

http://heetgasmodelbouw.ridders.nu/Webpaginas/pagina_tweetakt_motor/tweetakt_frameset.htm

Old steam engines lent themselves to this conversion because both sides of the piston were sealed.  The closed off part  behind the piston acts like the sealed crankcase on a normal 2-stroke engine.  A transfer port connects the back half of the cylinder to the front half and allows the fuel mixture to be transfered into the combustion chamber.

I assume you already know what a hot tube is?

Chuck


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## Goldflash (Oct 8, 2012)

Hi Chuck I would be really interested in seeing how your Spring Loaded ball valves work 
Ralph


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## Brian Rupnow (Oct 8, 2012)

Okay Chuck---I did know how a two stroke worked. I have a "motor anthology" from 1913 that explains the hot tube quite well. i will have to read up on that. From what I remember (its been 30 years since I last read the book) there was a seperate reservoir of alcohol that one had to light first to heat up the hot tube before cranking the engine. I can't remember if the hot tube then gathered its heat from the engine exhaust or not. I'll have to go read the book tonight. All the two stroke engines i have known were high revving little monsters, but the videos I have watched of Bessemer type engines were quite slow.---Might have something to do with that "Out of proportion" flywheel.---Brian


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## Brian Rupnow (Oct 8, 2012)

I went and read the book regarding "hot tube" ignitions. I had it partly right.---Sorta----The ignition tube was made of platinum, and sat where a sparkplug would normally go. Part of the tube was inside the cylinder head, and part protruded from the cylinder head. There was a small tank of Benzine right by the dashboard, that was a gravity feed to a bunsen burner like device (one for each cylinder). Each of these bunsen burner like devices had its own alcohol reservoir surrounding it. To start the car, you filled each burners alcohol cup and lit it on fire. This heated the burner to the point that any Benzene delivered to it would immediately vapourize. It was the flame from the vapourized Benzene that heated the platinum hot tube hot enough to cause ignition of fuel in the cylinders as you cranked the engine.


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## cfellows (Oct 8, 2012)

Here's a link to some good info on operation of a hot tube.  

http://www.old-engine.com/maghtu.htm

The hot tube does need to be heated by an external source before starting the engine.  Once the engine is started, the fuel mixture is pushed up into the hot tube by the compression stroke where it ignites, also igniting the rest of the mixture in the cylinder.  On many of the engines, the ignition of the mixture inside the hot tube was enough to keep it hot and the external heating source could be switched off.  

Hot tube engines can be timed by making the hot tube longer or shorter or by moving the hot spot closer to or further away from the cylinder.

As far as running speed, I imagine and am hoping that the larger flywheel combined with a really long stroke will allow the engine to run much slower.  And, of course, throttling and fuel mixture can also speed up or slow down the speed.

This whole 2-stroke thing is a bit of a new experience for me to, so I imagine I'll doing some experimenting once I get it running. 

Chuck


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## ShopShoe (Oct 8, 2012)

FWIW, I have seen early two-stroke IC engines described as "compound" gas engines.

--ShopShoe


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## Brian Rupnow (Nov 6, 2012)

Chuck---Whats happening? Are you hung up on this project, taking a break, or posting elsewhere? I hope you are well and have no health issues. I am very interested in this build.---Brian


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## cfellows (Nov 7, 2012)

Brian Rupnow said:


> Chuck---Whats happening? Are you hung up on this project, taking a break, or posting elsewhere? I hope you are well and have no health issues. I am very interested in this build.---Brian


 
Hi Brian,

Thanks for your concern.  Right after we got back from vacation on Oct 1st, I came down with a nasty case of something resembling a bad cold and couldn't shake it.  It's taken almost 6 weeks and two different rounds of antibiotics but I'm finally pretty much back to normal.  Never was flat on my back, but just sick enough that all I felt like doing was sitting around in my pajamas and moaning a lot.  

I cleaned my shop up a couple of days ago and as soon as I get caught up on the backlog of honeydo's I should be back in full swing on the Bessemer.

Thanks again...
Chuck


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## Brian Rupnow (Nov 7, 2012)

Glad to hear you are well. I have had a rough fall myself, but seem to be on the mend now.----Brian


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## larry1 (Nov 7, 2012)

Chuck,   Glad to hear that you are well, again.    larry


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## cfellows (Nov 20, 2012)

After what seems like a lifetime, I'm finally able to get back into the shop and get to work on this engine.  I'm trying to catch up and figure out what the next step is going to be.

I've decided that I need to get the cylinder and piston machined.  I would like to make the piston out of aluminum for weight considerations, but it's more complicated than that.  First, because of the intake and exhaust ports in the cylinder, I don't want to use piston rings if I can get away from it.  That means that the piston is going to have to be a really close fit if I have any hope of getting the required compression.  So, I'm concerned that an aluminum piston would have a different heat expansion rate than the steel cylinder meaning I might need too much clearance when the engine is cold.  This leads me to think I probably need a cast iron piston which would have close to the same expansion rate as the steel cylinder.

Anybody got any thoughts on this?
Chuck


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## modelman1838 (Nov 20, 2012)

Hi Chuck
 If I were you I would definately stick with cast iron piston material in a mild steel or cast iron cylinder as I am sure the differential expansion coeficients will creat a problem, but after saying that if I remeber correctly all those little model aero engines used to run a light alloy piston in a precision lapped steel liner and these were all compression ignition so needed good compression, but they did have a contra piston which may have helped.
 Hugh.


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## idahoan (Nov 20, 2012)

Hi Chuck

My vote would be to use a cast iron ring or rings and pin them to keep them out of the ports.
Its good to see you back in the shop by the way.

Dave


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## cfellows (Nov 20, 2012)

So I'm going to go with the cast iron piston.  And, I'll attempt to get it to work without piston rings first.

Unfortunately, I don't have a lot of experience lapping.  Does anyone have a link to a website where I can brush up?  Don't want to invest a lot in tools if I don't have to.  I do have some clover valve lapping compound, both course and fine.  And I've got a bunch of different grades of diamond lapping compound.  

The cylinder is a piece of DOM tubing with a very smooth bore.  I'm assuming it's probably also pretty uniform in diameter but I'll need a way to check that.  

Lapping the piston to fit the cylinder seems like the trickiest part.  I would be happy to see some info on that if anyone has some to offer.

Chuck


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## Goldflash (Nov 20, 2012)

Hi Chuck 
When I built my Hot air Engine for the Power cylinder I bought a Brake Cylinder Hone from the local automotive accessory shop ( You can adjust the pressure on these ) and it cost about about NZD$19,00 which would be about USD$15.00 and it worked really well and gave me a true bore with a nice cross hatch finish ( I used CI Piston in a Stainless Steel cylinder )  The piston I just turned to Size and polished the OD with 800 Grit wet and dry paper wrapped round a bit of flat plate to give a parallel finish to the piston.  It worked and I got a good finish with a nice parallel piston that had about 0.001" clearance. ( I am planning to Teflon Coat the piston so I can run it dry without any lubricant )  
With regards to Piston Rings as I want to build a similar type of Engine I would talk to people who do repairs to Weed Eaters and see what they have available as some of the smaller weed eater pistons are in that 1.25-1.5  inch range etc. If your ports are not that big then I dont think you really have to worry about pegging the rings as the old two stroke bikes I played around with as a kid had fully floating piston rings 

Regards Ralph


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## Brian Rupnow (Nov 20, 2012)

Chuck--I am far from being expert---but---here's what I have learned. Firstly, the piston should be about .001 undersize from the bore inner diameter. I have had my best results using 600 grit abrasive in an oil base. You have to have some kind of handle on the piston---the connecting rod works just fine. Coat the i.d. of the cylinder with lapping compound and wiggle the piston a bit untill you get it started into the cylinder. It won't want to go in, as the .001 clearance is damn tight when you get the lapping compound on there. I put the cylinder in a vice so it can't run away on me, and work the piston back and forth (full stroke) in the bore. this requires a certain deftness of hand, as you don't want to push the piston all the way out the far end, nor pull it out from the near end. After you work it back and forth about a dozen times by hand, it will get much easier. You should now be able to rotate the piston in the cylinder, by hand.  Now comes the terrifying part!!! Set your lathe on its slowest speed and grip the cylinder in the chuck, with the con rod hanging out the opposite end where you can grip it. Hold the con rod firmly in your right hand, say a short prayer, and turn the lathe on, while holding your breath and with your left hand poised over the stop button.  If you have lived a good clean life, as I have, the cylinder will start to rotate, and the piston will not rip your arm out of the socket. As the cylinder rotates (I stress SLOWLY), work the piston through its full stroke in teh bore, being carefull not to push it all the way through nor pull it all the way out. Let the lathe run for about two minutes while working the piston through its full stroke. Shut the lathe off. Say another short prayer (Thank You, this time.) You're done!!!  The piston and the bore should both now have a uniform dull color. Please note---This is what I DO. If anyone else tries this and ends up like that guy who was always being chased on The Fugitive, don't come looking for me.---Brian.


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## Goldflash (Nov 20, 2012)

Chuck further More to cylinder bores after honing or lapping.
Boil them for half an hour in hot soapy water to get the minute abrasive particles out that have embedded themselves in the surface of the Bore or piston.  
The Heat opens up the pores of the metal and allows the embedded particles to fall out  
You will be surprised how much black dirt will come out when wiping through  with some white tissue paper/ rags etc. 
Then remember to oil the parts afterwards to stop rust. 
used to build multi-stage compressors up to 11 inch bores and we always boiled the cylinders after honing. Better to wear in than wear out.  



 Regards Ralph


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## Jasonb (Nov 21, 2012)

Have a read of Ramon's thread on his pair of tigres and also my one on the Firefly, both have CI pistons lapped to the bore.

http://www.homemodelenginemachinist.com/f31/super-tigre-g32-1cc-diesel-5cc-version-17674/

http://www.model-engineer.co.uk/forums/postings.asp?th=70308


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## cfellows (Nov 21, 2012)

I've got the cylinder pretty well finished I think.  I found a piece of aluminum tubing that was just a tad bigger than the ID of the cylinder.  I cut across the tube about 2/3 of the way through, than slit the tube from the end to the cross cut.  The length of the slit is about 1/2" longer than the cylinder.  





I then mounted the tube in my lathe and used CLover fine lapping compound and made numerous passes through the cylinder from both ends with the lathe running pretty slowly.  I wiped down the lap, applied just oil, then made more passes with the cylinder.  I repeated this process 5 or 6 times.  I've got a nice finish with no sign of circular tool marks.  Also, no measurable taper.




I doubt if you'll find this method in any of the books of best practices, but it seems to have worked well for me.  After I've turned the piston down I plan to lap it into the cylinder.  Never done that, so I will use the info Jason provided plus whatever else I can find on the net.
Chuck


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## cfellows (Nov 22, 2012)

I've finished the piston and got a really nice fit in the cylinder.  I first turned the piston oversize by about .010", then mounted it onto the piston rod shouldered down to 1/4" x 20 threads.  After the rod was tightened as much as I could get I finished turning and polishing the piston to size.




I also mounted the two crosshead guide bottoms.  They are made from left over pieces of the engine frame, are 4" long and 3/8" thick.  I purposely left them oversized and rough on top.  I'll mill them flat and to size in the assembled position to assure I get them parallel with the cylinder.




The guides are attached to the frame with socket head cap screws from the inside so they look like an integral part of the frame.




Chuck


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## cfellows (Dec 13, 2012)

After a bit of a sabbatical I got back to work on this engine today.  I made significant progress on the crosshead piece.




I was a bit skeptical about my ability to get everything lined up so the piston and rod would slide easily, but, through luck and/or patience, I seem to have gotten it right.  
Chuck


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## Brian Rupnow (Dec 13, 2012)

Great Stuff, Chuck. I was beginning to wonder what had happened to you. Nice project.---Brian


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## idahoan (Dec 13, 2012)

Hi Chuck

Great work on the Bessemer!

Thanks for the update,
Dave


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## rleete (Dec 13, 2012)

cfellows said:


> but, through luck and/or patience, I seem to have gotten it right.


 
Highly advanced skill.  Never admit to anything else.


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## cfellows (Dec 15, 2012)

So I'm getting serious about starting work on the transfer port which will move the fuel mixtue from behind the piston to the combustion chamber.  It will be about 2" long and I'm wanting to make it 5/32" inside diameter.  Keeping in mind this will be a low RPM engine, does anybody think the transfer port needs to be bigger?  

Chuck


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## cfellows (Jan 24, 2013)

Well, the holidays are over, the much loved kids and grandkids have moved into their own house and I seem to be pretty well recovered from my second case of the creeping crud in as many months.  Oh, and the detour for the Lister engine is now behind me.  So, time to get back to work on the Bessemer.

After much deliberation, I've decided to use the pressure controlled fuel transfer port used by Jan Ridders on his vertical 2 stroke.  I like the idea of having the inlet port in the head rather than middle of the cylinder and in letting the pressure control the fuel inlet instead of the port.  Jan seems to get pretty good results with his setup and I'm hoping for the same.
You can see in the picture I've drilled a hole in the bottom of the cylinder and tapped it for 1/4" model pipe taper.  I threaded in an elbow and will hook up the rest of the plumbing as I get it built.  If 1/4" turns out to be too small, I can always step it up to a 1/16" npt.






By the way, I figured out how to use Dropbox to host photos.  Much faster and simpler than Photobucket.

Chuck


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## cfellows (Jan 25, 2013)

This is what the transfer port assembly should look like...






Pretend there is an opening from the rightmost elbow into the back of the cylinder.  Forgot to draw it! 

Pipe and fittings are all 1/4" model taper.

Chuck


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## skyline1 (Jan 25, 2013)

Hi Chuck
Been looking at this
 have I got the timing right it's a sort of two stroke but uses the lower half of the cylinder as a compression chamber rather than  the whole crankcase ?


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## cfellows (Jan 25, 2013)

skyline1 said:


> Hi Chuck
> Been looking at this
> have I got the timing right it's a sort of two stroke but uses the lower half of the cylinder as a compression chamber rather than  the whole crankcase ?


 
Yes, the back half of the cylinder pulls in the fuel mixture on the upward stroke of the piston, then compresses it and pushes it into the upper part of the cylinder toward the end of the power stroke.  All the original two stroke engines like his had a transfer port from the bottom of the cylinder into the middle of the cylinder where the piston would uncover it near the bottom of the power stroke.

I'm using a little bit different arrangement designed by Jan Ridders where the fuel mixture is admitted through the cylinder head.  Admission to the top of the cylinder is controlled by ball check valves and a pressure drop in the top half of the cylinder when the exhaust port is uncovered.

Chuck


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## cfellows (Jan 25, 2013)

More work done on the Bessemer today.  The two check valve assemblies started out as 1 1/2" long pieces of 3/8" brass hex.







The main valve body is 7/8" long and the remainder is turned down to 1/4".  A 1/8" hole is drilled straight through, then a #5 hole is drilled in the larger, valve body.  The tip of 1/4" pipe is a male, 1/4" model pipe taper thread.  The other end is a female 1/4" model pipe taper thread.






To complete the valve assemblies I added a 3/16" ball bearing and a spring.  The springs might be too long and require some trimming.






I had to order some more elbows from PM Research so in the mean time I'll get started on the cylinder head.

Chuck


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## Brian Rupnow (Jan 25, 2013)

Chuck---I'm finding this build quite fascinating. Since there are no oil wells in the part of Ontario I come from, I had never heard of this type of engine or engine conversion before you started this thread. Up where I come from we don't have any oil, just lots of uranium. We all glow a bit in the dark!!!


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## cfellows (Jan 26, 2013)

Brian Rupnow said:


> Chuck---I'm finding this build quite fascinating. Since there are no oil wells in the part of Ontario I come from, I had never heard of this type of engine or engine conversion before you started this thread. Up where I come from we don't have any oil, just lots of uranium. We all glow a bit in the dark!!!


 
Thanks Brian!  As for the uranium, take heart... maybe you've developed a natural immunity to fallout.

Chuck


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## BronxFigs (Mar 25, 2013)

Have all the photos been moved somewhere else?  Another example of a now, useless, engine construction tutorial.  Are we supposed to guess what's going on?  Too much of this nonsense throughout this forum.  

Frank


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## Brian Rupnow (Mar 25, 2013)

BronxFigs said:


> Have all the photos been moved somewhere else?  Another example of a now, useless, engine construction tutorial.  Are we supposed to guess what's going on?  Too much of this nonsense throughout this forum.
> 
> Frank


 
I still get the pictures fine. Check your computer settings.---Brian


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## LSEW (Mar 25, 2013)

In the interest of model engines running on a hot tube, here is a video of the Swan oil field engine.

[ame]http://www.youtube.com/watch?v=nz4Li92N7HA[/ame]

maury
www.lonestarengineworks.com


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## BronxFigs (Mar 26, 2013)

Brian...Thanks for the advice, but how do I check my settings?  I'm really not very good with computers, so any help would be appreciated.  I've been finding that I cannot "see" photos in more than a few threads on this forum, yet, in some threads, the photos are there.  What am I doing wrong?

Frank


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## Brian Rupnow (Mar 26, 2013)

You are not logged in properly. This has been an ongoing problem ever since the forum changed hands. Send a note to Austin the owner of the site, He will get you fixed up.---Brian


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## cfellows (Mar 26, 2013)

LSEW said:


> In the interest of model engines running on a hot tube, here is a video of the Swan oil field engine.
> 
> Maury


 
Hey Maury, 

That engine really looks and runs nice.  I'm gonna have to see that hot tube.  Did you make the burner as well?


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## BronxFigs (Mar 26, 2013)

Brian...

Thanks for the advice.  I will let the forum owner know of  this ongoing problem...I had no idea.

Frank


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## LSEW (Mar 26, 2013)

Chuck, you will have to get the compression ratio about right so it fires at the top of the stroke, too low and it won't fire, too high and it will break your wrists.

The burner is a cheap HF burner run off a grill regulator. and for fine tuning, a needle valve.

maury


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## cfellows (Jul 1, 2013)

Time to bring this project out of cold storage, thaw it out and get it going again.  I started work today on the fuel transfer assembly.











I'm using 1/4" model plumbing parts for starters.  The internal diameter of the piping is 5/32", which I hope will be large enough.  If not, I may have to revert to 5/16" model plumbing parts which I do have on hand.  The hex shaped piece on the left will be a ball check valve which prevents compression from blowing the fuel mixture back down the pipe.  Now I have to make a second ball check valve which attaches to the TEE.

Chuck


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## cfellows (Jul 2, 2013)

Still a few unknowns between here and the finish line.  I got the cylinder head pretty well finished today.  
















The hole is threaded M10 x 1 to allow the use of a spark plug if my efforts with the hot tube fail.  Still have to cut the port which will let the fuel charge into the cylinder but I have a final connector to make before I finalize the head.

Chuck


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## jwcnc1911 (Jul 2, 2013)

I love those little brass fittings!  What's your source for those?


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## Brian Rupnow (Jul 3, 2013)

Chuck--I'm happy to see you back on this particular build. I am fascinated by this type of engine, and I learn from your posts.---Brian


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## cfellows (Jul 3, 2013)

jwcnc1911 said:


> I love those little brass fittings!  What's your source for those?



Those come from PM Research.

http://www.pmresearchinc.com/

They sell the castings in little "trees", 3/16", 1/4", and 5/16".  They're pretty inexpensive as well.  They also sell the nipples, but I just use brass tubing or drilled out rod.

Chuck


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## cfellows (Jul 3, 2013)

Brian Rupnow said:


> Chuck--I'm happy to see you back on this particular build. I am fascinated by this type of engine, and I learn from your posts.---Brian



Thanks, Brian, always enjoy knowing you're watching.

Chuck


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## cfellows (Jul 4, 2013)

I wanted to use hex nuts and studs to hold the head on but normal hex nuts for 10-24 screws, which are 3/8" across the flats, are not proportioned right for model work.  Instead, I bought some all-thread coupling nuts from the local Ace Hardware and was able to get 3 model nuts from each coupling nut.






These coupling nuts are about 3/4" long and 5/16" across the flats.  The model nuts, which may still be a bit too thick are .2 inches tall.

Chuck


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## cfellows (Jul 4, 2013)

Here's the fixture which will serve as the intake manifold, for lack of a better name...






And here's a shot of the plumbing, at lest the hardest part of the plumbing...






Now it remains to be seen how well it seal up.  May have to resort to some loctite and soldering to eliminate any leaks.

Chuck


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## hitnmiss49 (Jul 4, 2013)

Can't wait for the video on this engine Chuck. I know it is going to sound great. You sure are doing an excellent job just like you always do.

Lonnie


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## myrickman (Jul 4, 2013)

Chuck- since your cylinder is a piece of thick tubing, have you considered milling a slot on the underside of the cylinder to form the transfer port.  After you get the entrance holes to the cylinder, you could braze or solder a cover piece on and take a skim cut on the entire cylinder OD.  Still, it will be interesting to see this uniflow  scavenged design of yours run. I'll have to see Jan's pics of his... Great build, keep the progress pix coming. MM


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## cfellows (Jul 5, 2013)

Thanks, Lonnie, MM.  I had considered different ways to build the transfer port into the cylinder, but then decided on Jan Ridder's concept so I could get  by with one less hole to drill in the cylinder.  Lots of new ground for me with this engine, so I'm more than a little concerned about my ability to get it running.  

Got the connecting rod well under way this evening.  After I got the material for the connecting rod cut to size (6.125" x 1" x 0.5") and marked up, I first drilled the holes in the end which will house the rod cap screws.  This was done on my drill press with the rod blank clamped on end in my drill press vice.







Unfortunately I forgot to take pictures of the next few steps, but, after drilling the holes in the end, I cut the rod cap loose from the connecting rod.  I then shaped the rod cap and drilled out the holes.  Next I tapped the connecting rod, then re-fastened the rod cap to the rod with screws.  Then it's off to the mill/drill to bore the 1/2" hole for the big end of the connecting rod.






Next I drilled the 1/4" hole for the small end of the connecting rod.






Next I used a 1/2" end mill and plunge cut both ends of the narrow portion of the rod.






Then I cleaned out the waste between the end-cuts.  Tomorrow, if the spouse doesn't find something better (in her mind) for me to do, I'll finish up the connecting rod.  

Chuck


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## robcas631 (Jul 5, 2013)

Wow! Where can one buy model plumbing?


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## robcas631 (Jul 5, 2013)

Very cool indeed!


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## cfellows (Jul 5, 2013)

robcas631 said:


> Wow! Where can one buy model plumbing?



Model pipe fixtures were purchased here:

http://www.pmresearchinc.com/store/home.php

You can buy the castings at a very reasonable price or finished fixtures for a bit more.

Chuck


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## cfellows (Jul 5, 2013)

So, here's the finished connecting rod.  It has a few dings on the bottom side since my work holding set-up wasn't quite up to the task... actually, it would have been fine if I'd simply tightened the vise handle before I started milling!   :embarassed:






And here's a few shots of the engine mostly assembled.





















Chuck


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## Brian Rupnow (Jul 5, 2013)

Chuck--That is one very slick looking engine. I really hope it runs as good as it looks. You continue to be an inspiration to me.---Brian


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## cfellows (Jul 9, 2013)

Thanks, Brian, for the kind words.  I had to backtrack a little.  I mis-measured somewhere along the line and had to move the cross-head guides back a quarter of an inch.  Not a trivial task for me since I had to get them at just the right height and perfectly parallel to the cylinder.  






After getting that sorted out, I went ahead and made the adjustable piece that goes into the packing gland to compress the packing string.






I ordered some more graphite string today.  A fellow at G.E.A.R.S. last fall gave me a length of it, but I have no idea where I put it.  Sure it will turn up again after I no longer need it.

Chuck


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## CarlByrns (Feb 2, 2014)

I've been watching this thread for some time now- has there been any progress on this engine or has is been shelved for some unfortunate reason?


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## cfellows (Feb 2, 2014)

Yeah, I had set it aside for some other projects I preferred to work on.  I do want to finish it and I'm thinking I'll get back to it soon as I finish my vertical single 4 stroke engine.

 Chuck


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## CarlByrns (Feb 3, 2014)

cfellows said:


> Yeah, I had set it aside for some other projects I preferred to work on.  I do want to finish it and I'm thinking I'll get back to it soon as I finish my vertical single 4 stroke engine.
> 
> Chuck



Thanks. I'll be looking for it- I have wanted to build a hot-bulb engine but could never figure out the fuel delivery or cylinder head.


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## cfellows (Feb 19, 2014)

I'm waiting on some parts for my propane fuel project, so I'm pulling the Bessemer project off the shelf, dusting it off and evaluating where I am with it.  Today I finished fitting the fuel transfer plumbing to the cylinder and head.  











 If you recall, I'm using Jan Ridders pressure controlled fuel transfer design.  I will likely have to make some adjustments to seal up all the leaks and am more than a little worried about how well I'll be able to get that done.  I did buy some graphite string to pack the gland around the piston rod.  I'm also a little concerned about the fact that I don't plan to use a piston ring since that gets pretty complicated on 2 stroke engines.

 I'm also planning to try a glow plug first since I've had pretty good luck with that on my plumbing parts engine.  It also obviates the need for points. 

 The next thing I'll complete is the taper collet to secure the flywheel to the crankshaft.  Then we'll see where I go from there.

 Chuck


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## cfellows (Feb 19, 2014)

Got the flywheel cone collet nearly finished.  I started with a piece of 1.5" round rod and shouldered down the end.  The spigot is 1 5/16" long, which is the thickness of the flywheel hub and 3/4" diameter, which is the major diameter of the collet taper.






 Next I turned the taper using the compound which was set to 3 degrees.






 After boring and reaming the collet to 1/2", I separated it from the work piece with my 4" band-saw.  Then I mounted it on an expanding mandrel and turned the big end flat and smooth.






 Here it is sitting on the crankshaft.  I'm probably going to shorten it about 1/4"...






 I drilled 8 holes around the perimeter for 8-32 SHCS.  Every other hole is tapped for jack screws which will be used to remove the flywheel.






 Next I'll bore the taper in the flywheel, then cut the slot in the collet.

 Chuck


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## cfellows (Feb 19, 2014)

Been a long day in the shop, my back and feet are complaining loudly.  But I finished fitting and securing the flywheel.  Without changing the compound setting, I chucked up the flywheel and (carefully) bored the taper for the collet.






 Here is the collet test fitted in the flywheel.  I left a gap of about .150 for plenty of adjustment.






 Here is the flywheel fitted to the crankshaft.  The soda can shows the scale of the engine.  It's 18" long from the front of the head to the back of the flywheel, which is almost 9" diameter.  The cylinder is 4" long and 2" diameter.






 It occurs to me that I'm not that far from trying to start it.  A few more odds n ends and I should be ready.

 Chuck


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## cfellows (Feb 20, 2014)

Here's a short video of the Bessemer showing the compression.  

[ame]http://www.youtube.com/watch?v=gBdWJWWhbxo[/ame]

I'm pretty happy with it considering there are no piston rings.  The check valves seem to be holding as is the transfer port plumbing, so I'm encouraged by the results.

Chuck


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## Generatorgus (Feb 21, 2014)

Chuck, good to see your back on the Bessemer.
That's real good compression for no rings, I like the collet too.
Looking forward to seeing it fire up.
GUS


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## johnmcc69 (Feb 21, 2014)

I can't wait to hear what this one sounds like when running!

 John


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## cfellows (Feb 22, 2014)

Thanks, Gus, John.  I'm getting anxious, but trying to be careful and get things right.  

 Today I cut a 1/8" deep pocket in the top of the piston to reduce the compression ratio some.  After trying to turn it over by hand I felt it was a little too high.  I also cut the exhaust port and polished up the exterior of the cylinder.






 Seems like I spent a lot of time in the shop today, but didn't get all that much done.  I guess I spent a lot of time thinking about the water jacket.  I almost started to cut fins in the cylinder and make it air cooled, but decided to stay with the water cooling so it would look more authentic.

 Next I have to cut out a spool shaped space in front of the exhaust port and shrink fit the water jacket, after I silver solder a couple of pipe connectors in said water jacket.

 Chuck


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## robcas631 (Feb 22, 2014)

Excellent work!


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## cfellows (Feb 23, 2014)

Thanks, Rob.

 Today I finished up the water jacket.  I started with 2" OD DOM steel tubing.  After turning both ends square, I mounted the piece in my milling machine vise to drill the holes for the threaded bushings.  First  a 5/16" hole...







 Then I used a 3/8" diameter end mill to create a shelf.






 Here's a couple of pictures with both bushings silver soldered into place.











 Here I've cleaned it up and threaded the bushings with a 1/4" model pipe taper thread.











 The hot water will exit out the top, front of the water jacket, the cool water will enter at a 45 (135) degree angle from the back lower quadrant.
 Tomorrow I'll shape the front part of the cylinder.  Then I'll either press or heat shrink the water jacket in place on the cylinder.  Gonna be tense!

 Chuck


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## aonemarine (Feb 24, 2014)

Chuck, I just love the work you do and the way you think. Maybe one day you will be at the cabin fever expo so I can meet you in person. I am sure there are many others on here that would like to meet you there as well.....


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## cfellows (Feb 24, 2014)

aonemarine said:


> Chuck, I just love the work you do and the way you think. Maybe one day you will be at the cabin fever expo so I can meet you in person. I am sure there are many others on here that would like to meet you there as well.....



Thanks, your comments mean a lot.  Never been to Cabin Fever, but maybe I'll give next year's expo some serious thought.

 This morning I finished shaping the cylinder for the water space and got the water jacket pressed into place.  A little tense and scary, but it worked out perfectly in the end.  

 I started by cutting the cylinder to .010" larger than the ID of the water jacket, then began cutting out the water space.






 Here's a photo of the shaped cylinder and the water jacket.  The outboard end of the cylinder is .010" smaller than the inboard end and the ID of the water jacket is also .010" smaller on the outboard end.  This let me slide the water jacket most of the way over the cylinder and line up the water exit with the exhaust port before pressing it into place.






 I pressed the water jacket onto the cylinder using my 20 ton hydraulic press.  Fortunately, it wasn't much of a struggle, so I think the .010" interference fit was about right.






 I think I'm at a point where I can reassemble the engine.

 Chuck


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## cfellows (Feb 24, 2014)

I think it's going to be a runner!!!   It's back together and I've gotten it to fire a few times.  Just need to put together an air bleed for the vapor fuel tank/carb and I think it will run!  I'm pumped!

Chuck


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## cfellows (Feb 24, 2014)

Looks like I'm going to have to install one or more piston rings.  Turns out I don't have enough compression without squirting some oil in the cylinder.  Unfortunately, it's going to have to be pinned so the ring gap won't pass over the exhaust port.  Anybody got information or a link to making a pinned piston ring?  

 Chuck


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## johnmcc69 (Feb 24, 2014)

I've seen roll pins installed radially in the ring grooves & the rings radiused on the ends to wrap around the pin. Half dia. Opposite on each end of the ring.

 John


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## cfellows (Feb 25, 2014)

johnmcc69 said:


> I've seen roll pins installed radially in the ring grooves & the rings radiused on the ends to wrap around the pin. Half dia. Opposite on each end of the ring.
> 
> John



Thanks, John, think that's exactly what I'll do.

 I'm following a write-up in Model Engine Builder that details making rings both from steel and cast iron.  The write-up goes into a lot of detail about theory and is a bit over my head.  But I think I've got enough out of it to give it a go.  Basically, instead of cutting the ring to a finished diameter then expanding through heat treating,  the article advocates turning the ring to a finished diameter that is oversize, then cutting a gap that will allow squeezing the ring down to the cylinder bore.

 I'm using cast iron since that's the only material I have on hand that is about the right size.  The cylinder bore is 1.260" and here I've turned the outside diameter to 1.294".  Here I've begun boring out the center.






 In this photo I've finished boring the center to the desired ID of 1.106".






 And here I have parted off two rings.  I plan to only use one, but fully expect to break or otherwise damage one of them.  I also have enough turned stock left to make another 5 or 6 rings if needed.






 Chuck


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## cfellows (Feb 25, 2014)

Against all odds, I got the piston ring made, the pin installed in the piston and the whole assembly put back together.  And I even managed to do it all with 1 ring, didn't have to go to the second one.  Here's a picture of the ring after I cut the gap with a dremel tool and abrasive cutoff blade.






 Don't have pictures, but next I mounted the ring in my milling vise and used a 1/16" end mill to cut the ends of the gaps back to the right distance and with a 1/16" diameter contour on ech end.  Here's a picture of the ring inserted into the cylinder bore and the pin inserted into the round gap.






 Next I drilled a 1/16" hole in the ring groove on the side of the piston. 






 Then I pressed the 1/16" roll pin into the hole.  I used my Dremel tool with a cutoff blade to grind the pin down below the surface of the piston.






 After reassembling everything, I have better compression, but still can't get the engine to start.  It  pops and will sometimes fire several times on it's own but won't keep running.  The next thing is to install points and spark ignition.  Since it's a 2 stroke of somewhat unique design, I'm not sure how consistently the fuel mixture is getting to the glow plug.  I think the consistency and controllability of spark ignition will make a difference.  And from there, I need to install a real carburetor instead of the vapor fuel tank.

 Still got a few things to try and I'm still confident I'll get it running.

 Chuck


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## Generatorgus (Feb 26, 2014)

Hi Chuck, I'm probably not the one to be giving advice about the pinned ring, or rings at all for all that matters, as I got an F- in the ring making class.
But, in my experience with real size antique engines, the pin does not interfere with the normal end gap on the ring, but is fully encompassed by the ring.
I think what I mean that the pin should be smaller diameter and the ends of the ring should form the gap independent of the pin, and let the ring do it's own thing.
I'm guessing the pin would normally be no more than half the width of the ring.
You may lose compression at the double gap it causes and over the top of the pin.

I wish I could have said that before you did all the work, but it may be a non-issue anyway.

GUS


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## cfellows (Feb 26, 2014)

Generatorgus said:


> Hi Chuck, I'm probably not the one to be giving advice about the pinned ring, or rings at all for all that matters, as I got an F- in the ring making class.
> But, in my experience with real size antique engines, the pin does not interfere with the normal end gap on the ring, but is fully encompassed by the ring.
> I think what I mean that the pin should be smaller diameter and the ends of the ring should form the gap independent of the pin, and let the ring do it's own thing.
> I'm guessing the pin would normally be no more than half the width of the ring.
> ...


 
 Yeah, I agree that would be better.  Unfortunately, the smallest roll pin I had was 1/16" and I don't know if they even make anything smaller.  I didn't want to make the ring any wider as I had already made it about .010" wider than recommended and that would just increase the friction.  The ring gap ends are radiused to match the pin, but not deep enough to form a complete circle.  

 I had cut a 1/8" deep cup in the top of the piston to lower the compression ratio some and in retrospect, that may not have been a good idea.  If all else fails, I may have to fit a plug to raise it back up.  Or, I may cut the top of the piston off and go to a two piece piston, separated at the ring gap.  I've seen other folks do that and it sure makes installing the ring a lot easier.  I probably came real close to breaking that ring getting it installed.

 Chuck


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## t.l.a.r. eng (Feb 26, 2014)

Perhaps a much smaller hardened steel pin pressed into the piston ring land is needed. Most 2-cycle engines use very tiny hardened pins pressed into the ring land.
Drill the hole in the ring material before cutting off to accommodate the pin, then splitting the ring at the drilled hole when the ring is cut to width. 

Some engines I have seen offset the pin to the top or bottom, don't remember which at the moment, of the ring land as to leave more ring material to butt together. 

Hope that makes sense?


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## myrickman (Feb 26, 2014)

Nice build Chuck! I like how you attached the water jacket. Being a loop-scavenged engine you should have good purging of the spent fuel/air. These engines are finicky on the fuel to air ratio. I have the full sized version with a 7.5x12" bore and stroke and it refuse to run unless the mix is in one sweet spot. 
You might have better luck on propane but making the mixer is another device to fabricate. I feel your single ring should be adequate... If you are at say 4:1 compression ratio or better, it should go. Again, enjoying your build. I have a soft spot for the engines of the oil patch.


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## Generatorgus (Feb 27, 2014)

Chuck, a small piece of one of your old number drill bits or a new one for all that matters, should probably do nicely. I really don't think there is much shear stress involved.

This is from the webpage of the guy I buy my full size rings from.
Good tips about groove and end clearance and should apply to our small engines.
http://www.ringspacers.com/tips.htm


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## cfellows (Feb 27, 2014)

Thanks for the link, Gus, and to all for the comments and suggestion.  Very helpful and much appreciated.

 So, today I got the points installed and decided to work some more on the engine frame/base before trying to start it again... tired of it moving all over the place when trying to start it, not to mention the banged fingers and knuckles!

 I'm thinking of adding the 3" tall steel pieces to raise the engine so the flywheel clears whatever it's sitting on.  It also adds some weight.  
















 Thought I'd see if anyone has any strong opinions, one way or the other, before I move ahead.  Don't be shy!
 Chuck


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## Brian Rupnow (Feb 27, 2014)

Chuck--My vote is for anything that makes it easier on you and your fingers. It looks just fine raised up like that to me. I am following with rapt attention to see how this critter develops.----Brian


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## cfellows (Feb 27, 2014)

Brian Rupnow said:


> Chuck--My vote is for anything that makes it easier on you and your fingers. It looks just fine raised up like that to me. I am following with rapt attention to see how this critter develops.----Brian



Thanks, Brian. Guess that makes it unanimous 2 to zip.

I welded up the base. 






The sides are made from 3" channel iron with one side cut off.






The ends are made from 1.5" x 3" x 1/4" angle iron.






I'll bolt the engine to the base through the angle iron end pieces.











Chuck


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## larry1 (Feb 27, 2014)

Chuck, Im with Brian, whatever the easier for you. I like it sitting up, too.


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## Generatorgus (Feb 28, 2014)

That makes a very respectable looking sub base, and also way easier to work on.

I like your use ordinary structural steel.  But it's got to be a pain to cut the leg off.  Do you use a cutting torch, band saw or abrasive blades?  The abrasives would be my choice.

GUS


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## cfellows (Feb 28, 2014)

Generatorgus said:


> That makes a very respectable looking sub base, and also way easier to work on.
> 
> I like your use ordinary structural steel. But it's got to be a pain to cut the leg off. Do you use a cutting torch, band saw or abrasive blades? The abrasives would be my choice.
> 
> GUS


 
 I used my 4 X 6 band saw.  It wasn't too bad.  The channel iron was 11" long.  With the saw in the vertical position, I used a machinist clamp to clamp a piece of aluminum plate to the small existing table.  The top jaw of the clamp was beside the blade, slightly in front of the teeth.  After laying out my cut line, I held the channel iron horizontally on the table with the bottom pressed against the clamp jaw.  Then I began tilting the top of the piece forward into the blade by lifting the back.  I continued to lift, tilting the iron more and more until it hit the top blade guide.  At that point I was a little over half way through so I removed the piece, rotated it 180 degrees and repeated the process from the other end.

 It sounds and felt a little dangerous, particularly since the blade was trying to pull the work into the blade.  But I took my time and never really felt like it was going to get away from me.  I took me less than half an hour to completely cut through both side pieces.  Then went over each cut surface with an end mill and finished them off with my horizontal belt sander.

 Chuck


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## bobsymack (Feb 28, 2014)

Chuck why is it necessary to pin the rings ,I remember the 2 stroke detroits had a series of exhaust ports and the rings were never pinned.Excellent build by the way.
Vince


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## cfellows (Feb 28, 2014)

bobsymack said:


> Chuck why is it necessary to pin the rings ,I remember the 2 stroke detroits had a series of exhaust ports and the rings were never pinned.Excellent build by the way.
> Vince



I don't know the exact reason. It's generally suggested that allowing the ring gap to line up with the port(s ) can lead to unfortunate results.

I took the engine apart today and could see that the ring ends were pressing hard against the cylinder and the areas 1/8" or so away from the ends was not contacting the cylinder wall. So I took the piston out and honed the outside edges of the ring adjacent to the ring end. The Model Engine Builder article had suggested this was necessary, but I chose to ignore it at the time. The compression seems to be better now, but I still can't get it to run. 

I'm going to hook up an electric motor with a belt drive so I can turn the motor over while I fiddle with the fuel adjustments.

Chuck


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## cfellows (Mar 1, 2014)

I still seem to be getting compression leaks past the ring.  I don't think it's the gap, but maybe it's getting past some part of the OD.  I also measured the width of the ring groove which turned out to be a little over .006" wider than the ring.  Don't really know what the affect of that is, but it should probably less clearance.  Dang, I sure wish I could use an o-ring, so much easier and seems to work consistently...

 So, today, I cut the top off the piston down to the ring groove.  I drilled and tapped a 1/4-20 hole in the center of the piston so I can screw on a new piston top.  This will make installing a new ring easier.  I'm also rethinking the pinning mechanism.  The idea I like best for now is installing a roll pin radially that extends out into the ring groove by about half way or less, then cutting a small radius in the side of the ring to fit over the pin.  Logic tells me that if I do this fairly close to the gap, it will have less affect on the overall "springiness" of the ring.

 Chuck


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## Brian Rupnow (Mar 1, 2014)

Chuck--Is there any particular reason that you can't use a Viton o-ring?---Brian


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## cfellows (Mar 1, 2014)

Brian Rupnow said:


> Chuck--Is there any particular reason that you can't use a Viton o-ring?---Brian


 
 Yeah... from what I've read, sliding past the exhaust port would chew up the o-ring pretty quickly.

 Chuck


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## bobsymack (Mar 1, 2014)

Chuck would it be possible to chamfer the port from the inside and clean the sharp edge.


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## Brian Rupnow (Mar 1, 2014)

Yes, Chuck, you are right. I had forgot it was a two stroke.---Brian


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## cfellows (Mar 1, 2014)

bobsymack said:


> Chuck would it be possible to chamfer the port from the inside and clean the sharp edge.



I know that sounds like a reasonable solution, but I think the problem is that the pressure against the O-ring is still going to press the outer edge up into the opening, and while a smooth edge won't cut it, I think the constant beating wears it out in pretty short order...


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## Rustkolector (Mar 1, 2014)

Chuck,
Put your rings squarely in the cylinder and hold the cylinder up to a bright light. Look for any areas of the ring that are not contacting the cylinders squarely. .006" ring side clearance is too much on a new ring. It has to be tighter. When you redo your ring groove, lap the top and bottom faces with a sacrificial ring. Then lap the top and bottom ring faces to a nice polish to fit the groove. Try for .0005" to .0015" side clearance. making sure the ring groove is clean, and has about .010" radial clearance behind the ring. For reasonable compression in a new engine I think you're handicapping yourself with one ring. Two would be much better. I know that ring staking is a pain. Use a small dia. pin so that some portion of the adjacent ring ends form the ring gap. 

Jeff


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## t.l.a.r. eng (Mar 2, 2014)

Just a thought for what it is worth, pinned rings are for two strokes with wide slots for cylinder ports, and still need pinned even with bridges across the port "window".
Perhaps if this engine only uses relatively small round holes for ports, it may not need a pinned ring. It takes a window big enough for the ring tension to expand into the window, your ports may not be large enough for this to happen. 

May be worth your while to try a regular split iron ring first. Just thinking aloud.


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## cfellows (Mar 6, 2014)

I took the cylinder over to Maury's shop today and he graciously used his (very nice) Sunnen hone to fix up my cylinder.  It had a bit of a tight spot in the middle of the bore, but now it's a very nice fit over the whole length.

 So, now I'm wanting to add an oil cup to make sure I get enough lubrication.  Thought I'd include a drawing of my plan to see if anyone thinks this is about right or if there's a better arrangement?







 Seriously, I'm not at all sure this is the best placement of the oil cup in the cylinder and the oil groove in the piston.

 Chuck


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## aonemarine (Mar 6, 2014)

Chuck, to pin that ring, drill down thru the top of the piston and insert the pin so half its diameter creates a hump in the bottom of the rings groove then file the inside of the ring to clear it without disturbing the outer portion of the ring gap.....


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## cfellows (Mar 6, 2014)

aonemarine said:


> Chuck, to pin that ring, drill down thru the top of the piston and insert the pin so half its diameter creates a hump in the bottom of the rings groove then file the inside of the ring to clear it without disturbing the outer portion of the ring gap.....



 Good idea!  If I wind up having to go back to using a ring, I'll give that try.

 Chuck


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## bobsymack (Mar 7, 2014)

Chuck ,with it being 2 stroke would the vacuum below the piston cause it to draw in the oil from the cup
Vince


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## cfellows (Mar 7, 2014)

bobsymack said:


> Chuck ,with it being 2 stroke would the vacuum below the piston cause it to draw in the oil from the cup
> Vince


 
 Yeah, Vince, that's been brought to my attention on another forum.  I'm going to have to make the hole for the oil enter the cylinder where it won't be exposed to the space below the piston.

 Thanks...
 Chuck


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## Brian Rupnow (Mar 7, 2014)

Chuck--Any 2 strokes I have ever seen use a bit of oil with the gas to lubricate the crank and rod bearings, and inadvertently the piston. Could you possibly do the same and forget about the oil cup?---Brian


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## cfellows (Mar 7, 2014)

Brian Rupnow said:


> Chuck--Any 2 strokes I have ever seen use a bit of oil with the gas to lubricate the crank and rod bearings, and inadvertently the piston. Could you possibly do the same and forget about the oil cup?---Brian


 
 Yeah, I plan to mix oil with the gas.  But I kind of wanted the additional insurance of a cylinder oiler to reduce the possibility of wear on the piston since I'm using a steel cylinder.

 Chuck


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## aonemarine (Mar 7, 2014)

maybe put a spring loaded bb in the oiler so when the piston travels across it it lifts the bb to give a bit of oil??


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## cfellows (Mar 10, 2014)

I'm beginning to have thoughts of converting this engine to a 4 stroke.  I'm thinking I would make it a sideshaft engine and make my own helical gears.  I might be able to salvage the cylinder.   Just thinkin...


 Chuck


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## cfellows (Mar 12, 2014)

Today I tried starting the engine with a glow plug.  Turning the engine over with an electric motor, I can get the engine to fire about every other revolution, but it won't run on it's own.  At this point I think the problem is one of two things.  Either I'm not getting enough compression (there is still a bit of a leak), or fuel mixture transfer passageways are big enough.  I think tomorrow I will remake all the brass piping with 5/16" OD pipe and fittings with an ID of 7/32".  I'll also have to remake the two check valve assemblies with larger passageways and larger balls.  And, I probably need to find another spark plug and try again with spark ignition...


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## cfellows (Mar 23, 2014)

I'm back on the Bessemer.  Since I had such good luck with the Hall Sensor ignition on the Vertical Single, I've decided to go ahead and install a Hall Sensor on this engine.  I made small, dovetail milling cutter so I could cut a dovetail in the acrylic plastic.  This will hold the sensor down since it has a double bevel on the face that will slide under the edges of the dovetail.






 Here's the bare sensor in place.






 And here it is with the wiring attached.






 I've since epoxied the sensor to the piece of acrylic.  I tested it in place with my test circuit and the sensor is still working.  Tomorrow I'll make the magnet collar and I think I'll be in position to try starting it again.

 Chuck


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## cfellows (Mar 24, 2014)

Here's a video of me trying to start the Bessemer today.  I finished the Hall Sensor installation and have a good spark.  I also switched over to the carburetor I used on my vertical single.  

https://www.youtube.com/watch?v=XRPpR8kyWr0

 As you can see, it still won't run.  I think either my fuel intake / transfer plumbing is too small or I have too much compression leakage, although I don't think it's the latter.  So, I'm going to remake the plumbing increasing the size from 1/4" to 5/16".  The ID will go from 5/32" to 7/32" which will almost double the cross section of the pipe ID.  I also will make a new, larger carburetor for it.

 Chuck


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## aonemarine (Mar 24, 2014)

Chuck, take this with a grain of salt (on the rim of a glass)  but to me it is acting like a 2 stroke that has low compression and is not developing enough crank case pressure to get the air fuel charge to the combustion chamber. This could be piping as you suspect, but I also wonder if it could be related to the check valves. Are they spring loaded? 
   I'm used to a more conventional set up where the check valve is behind the carb feeding into the crankcase and the air fuel charge is shot into the cylinder by a piston port.  Think of drilling a hole thru the piston that would line up with a hole in the cylinder wall to get the air fuel charge into the combustion chamber after the exhaust port has been opened to create a scavenging effect.
    Hmm thought, put a exhaust pipe on it to see if you can create some cylinder scavenging....
I'm just babbleing, but sometimes I'm right....


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## cfellows (Mar 28, 2014)

aonemarine said:


> Chuck, take this with a grain of salt (on the rim of a glass) but to me it is acting like a 2 stroke that has low compression and is not developing enough crank case pressure to get the air fuel charge to the combustion chamber. This could be piping as you suspect, but I also wonder if it could be related to the check valves. Are they spring loaded?
> I'm used to a more conventional set up where the check valve is behind the carb feeding into the crankcase and the air fuel charge is shot into the cylinder by a piston port. Think of drilling a hole thru the piston that would line up with a hole in the cylinder wall to get the air fuel charge into the combustion chamber after the exhaust port has been opened to create a scavenging effect.
> Hmm thought, put a exhaust pipe on it to see if you can create some cylinder scavenging....
> I'm just babbleing, but sometimes I'm right....



I may be in denial, but I'm hoping against hope that this isn't a compression problem. If it turns out that is the problem, I'll make a new cylinder, convert the whole thing to a 4 stroke and use an o-ring!

A couple of days ago I decided to put this thing on the shelf more or less indefinitely and move on to something else. I have a pretty short attention span and not a lot of patience, not to mention a dwindling supply of energy as I get older. But, I decided to give it one more go.

I'm abandoning Jan Ridder's pressure controlled design and moving to a conventional 2 stroke transfer port.







I drilled a 1/4"hole for the fuel inlet into the combustion chamber and tapped it with a #16 - 27 pipe thread. I installed a 16 -27 threaded plug into the rear hole into the cylinder, also using Loctite. I left a bit of the plug protruding in case I ever needed to get it out, knowing all too well how I tend to put things together prematurely permanently! :wall: Next I drilled the 3/16" transfer port into the cylinder wall, from the bottom of the cylinder to where it meets the newly drilled 1/4" hole into the combustion chamber. I turned a small, brass plug about .005" oversize and drove it into the bottom of the cylinder to permanently plug the end of the transfer port, then filed it flush with the bottom of the cylinder. Finally, I installed the #16 elbow and nipple into the center intake port. Here is a picture from the back of the cylinder.






So, we'll see how this goes. 
Chuck


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## cfellows (Mar 29, 2014)

With the new, true 2 stroke setup, all the fuel mixture passages are now 3/16" diameter.  This morning I made a new, larger check valve.  This allows fuel from the carburetor into the transfer port, but will not allow a backflow through the carburetor when the fuel mixture is being transferred from the rear of the cylinder into the combustion chamber.  This valve has a 1/4" ball.






 Next, I cut some new profiles in the top of the piston.






 The smaller cut side is over the intake port.  The shape is designed to redirect the fuel mixture toward the top of the cylinder helping push the spent exhaust gases out the exhaust port.

 And, last, but not least... here is what we've all been looking forward to!

https://www.youtube.com/watch?v=vZ2kPzEUyXc

 Aahhh, success is sweet!

 Chuck


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## bobsymack (Mar 29, 2014)

Well done Chuck and no ring in any shape or form which proves another point.
Vince


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## Brian Rupnow (Mar 29, 2014)

Well done, Chuck. You can heave a big sigh of relief now. I know that engine has fought you right from the word go.---Brian


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## aonemarine (Mar 29, 2014)

*ITS ALIVE! ITS ALIVE!!*woohoo1


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