Tiny Inline 4 Cylinder IC

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I really like the radiator....I'll need to review that.


:bow: :bow:
Dave
 
Kel - what a brilliant little engine you have made. I have enjoyed every step of the way, and really appeciate your detailed thread. Looking forward to any minor remaining tweaks.

What's your next project? Whatever it is, I can't wait to watch it come together...
 
Thanks Guys!

Dave, I did not document the building of the radiator, I was not sure I was even going to use it. I can tell you it is made from 9 pieces of aluminum. Five 1/2" square aluminum bars drilled through and finned. The end caps are hollowed out, then there is an aluminum cover with 5 holes in it to receive the finned bars. It was then glued together with epoxy.

Richard, I still have not decided whats next. I am still working out all the kinks in this engine.

The rear main bearing has worn out more quickly since I put the baffle in. It seems that there is no oil getting to it, which seems weird since the front and rear are identical and the front is OK. I will be making a new bushing, this time putting small slots in the end to encourage oil into it.

I was seeing RPM numbers above 9000 again. I got her to peak at 9600 RPM.
I am using the S/S model engine CDI ignition. It is only rated at 12,000 sparks a minute, and at 9600 RPM that is over 19,000 Sparks per minute. So I am vastly over the so called Maximum.

This makes me think, What are you V8 guys using for CDI ignition? I know there was a discussion on this, but I can't remember what the outcome was.

Kel
 
Kel.
its always enjoying watching this engine in action.
love the sound of this little monster!

I can only dream of a multiple cylinder engine :bow:
need to start my first engine, have the tools. I think I am shying away from trying :(
using as an excuse would be my tractor hobby.

more videos please ;D
 
Kel, what an amazing project you must be so chuffed. :bow:
 
Hi Kel,
I have 2 ignitions, one a Jerry Howell design and one an S&S. I have used both of them on my 4 cylinder engine, which has the highest rpm of the bunch. They both seem to work fine except the Jerry Howell seems to make it run a little cleaner. By that I mean it revs up a little crisper but overall I can't tell much difference. Oh yeah, my 4 cylinder will hit about 8900 rpm.
George
 
Thanks Guys!

I think I found out why the rear main was getting no oil. When I took it apart to fix the bearing I noticed there was a ring of RTV sealant around the crank inside the engine. This was acting like an oil seal and preventing the oil from getting to the bearing. I have now installed a new bearing, minus the RTV sealant. I also filed tiny grooves on the bearings inner face, this should encourage oil into the bearing.

Now that I got her back together and started up again, the rear main is leaking. HOORAY!! Now I know it is getting oil. It leaks because there is no rear main seal, only an o-ring between the flywheel and block.

I am thinking about making some kind of mold to make seals out of RTV sealant. I am thinking about using acetal, as nothing seems to stick to it, and should make an ideal mold material.


Kel
 
Kel, I love the research and design mods you make on this engine. It is great to see someone take the time and energy to perfect their design. My hat is off to you. From beginning to present (I know it is not finish yet), you have done a fabulous job on this engine. Keep at it.
ironman (Ray)

 
Kel,
For molding your oil seal, you might want to try using Quick-Sil, sometime marketed as Quik-Sil, silicon putty. It is a two part silicon putty and not critical as far as measuring. Equal parts A and B and mix with your hands. Cures in about 5 minutes to demold and about an hour for full cure. Can be used to make food molds so it is non toxic. When molding it does not stick to anything except it's self so you can use metal molds if desired.

I don't know how well it would wear as an oil seal but it should be comparable to any silicon compound. I have used quite a bit of it for mold making for quick and dirty molds for epoxy parts. Shelf life of about a year but could probably be extended if it were refrigerated.

Many jewelery making suppliers have it and most of them have a small 3 ounce package for about $9. Sometimes shows up on e-bay and Micro-Mark used to carry it.

One supplier is:
http://www.esslinger.com/quick-silrubbermoldsiliconecompound-3oz.aspx

Their shipping is under $4 if you have it sent first class mail.

Gail in NM

 
Thanks for the tip Gail. That looks like some neat stuff.

I was thinking about making a metal outer race for the seal, and molding it directly into it. This would keep it from spinning, and hole it in place. I might need to incorporate some little fingers on the race to grab the silicone, and stop it from wandering. Also, how much smaller should I make the ID of the seal than the crank?



I am currently making plans for this engine and am quickly realizing that these multi cylinder engines are quite a chore to get right.

When it comes to things like head bolts, placements of pockets that are incrementally the same distance apart, or any other repetitive dimension, is it OK to only display said dimension on one of the features and then make a note saying that the dimension repeats?

I am trying to get all the parts to print in scale on an 8" x 11.5" piece of paper and make them as understandable as possible. The block and head are my biggest concerns. Is there a shortcut for bolt hole patterns other than what I stated above?

How do I communicate the starting point of an angled hole, like an intake runner intersecting the part at an angle? Do I show the center point of the hole on a 2-D plane, and then note to line up the bit to this mark after the angled setup is in place on the mill?

Kel
 
Hi Kel,
When I was taught drafting many years ago one of the primary rules was include enough dimensions so the reader wouldn't have to 'guess' what a dimension might be. As the draftsman sometimes we skip over a dimension because we know it and so therefore think that the reader would know it.
When I started working as a patten designer for Ford I was taught datum dimensioning. This form of dimensioning establishes a 'datum point' at a finished surface or true hole (not drilled) and from there any dimension for that datum plane is just a matter of using an extension line with the necessary dimension. Attached is the drawing for my V-twin crankcase. On it you will see that the centerline of the crankshaft hole is the Datum -0-, both for x and y. From there the dimensions to subsequent features are just an extension line with the proper dimension at the end of it.
As for dimensioning an angular feature, the origin has to come from some tangible point, a surface or a hole. That way the reader can set his wiggler, edge finder or tool to that feature, move over the required dimension and create the hole.
Believe me when I tell you this is not an easy task. As Steve has just stated about the drawings for his V-8, there are so many dimensions required and even though you as the draftsman think you have enough, ultimately you'll miss some.
George

View attachment V TWIN ENGINE SHT 1.pdf
 
Thanks George and Steve.

Ah yes, datum point. I am using that technique to show the location of the timing cover holes. I have heard it is not good to put dimensions on the part, or cross reference lines, but can I assume that this is unavoidable in certain circumstances?

Is is OK to have multiple drawings of the same plane? Sometimes I can't fit everything on one drawing, Like the hole locations for screws. Would two pages for the same part be OK? I will more than likely be making detailed diagrams of certain features, and this will take up precious space on the page.

There is over 60 holes in the head, even without dimension lines it is very cluttered. Could I make a separate drawing for each set of holes. Say one drawing for the head bolts, then a separate drawing for the valve locations and so on.

Then there is the spark plug holes, they are a compound angle, 30 degrees from the front and 7 degrees from the side. I am not even sure how to draw that accurately on a 2D plane. I spot drilled the hole locations on the bottom of the head, then set it up at angles on the mill, drilled the holes. Then flipped the head over and lined up a drill blank to that hole, then I milled it flat, and completed the threaded portion of the hole.

Also, I am not sure the terminology, but how about 'Stacking' dimensions. Lets say one feature is 1" away from the edge, then the next feature is .5" away from that. Or would I have to make the second dimension 1.5"?

Steve, I will definitely need these to be proof read, at least the block and heads. Any volunteers? :big: It would mean a free set of plans, but a trustworthy subject is a must, I do plan on copyrighting them.

Since I realize that there is a tremendous amount of work involved, I will be charging for them when finished. However since I am not a pro, what would a fair price be? I don't want to insult anybody, or short change myself.

Kel
 
Hi Kel,

I certainly enjoyed your recent videos of the little inline. It really wails.

It is my opinion that a part can be detailed on multiple sheets. I've worked with head, block, and crank drawings, for example that had many sheets. Some sheets had only section views that refered back to sections taken on other sheets of the drawing. My experience came from diesel engine design and production.

As a model engine builder, I'd rather have several drawings of the same view of a part to reduce clutter and help eliminate mistakes. So far I've only made drawings for my own use and even then it takes quite a bit of thought to get the dimensions on the drawing so they can be easily read. I make multiple drawings of the same part all the time. It is so easy with CAD.

As to stringing dimensions one dimension from another, I prefer to see them all from the same datum.

Good luck with your drawings and don't be afraid to put a good price on them. Anyone who goes to all this work to share a good design should be rewarded.

Regards,

Chuck Kuhn
 
kcmillin said:
Is is OK to have multiple drawings of the same plane? Sometimes I can't fit everything on one drawing, Like the hole locations for screws. Would two pages for the same part be OK? I will more than likely be making detailed diagrams of certain features, and this will take up precious space on the page.

If it helps, my head is 4 pages. The top and bottom of the head both took 2 of the same view to squeeze all the numbers into it.
 
Thanks for clarifying the 'multiple sheet' question. I have built engines from plans in the past, and even with a good set, there is a lot of 'Study' time involved to find out what certain dimensions are for, or where they are. Even going from one part to another to clarify why something is the way it is. So in my experience, it seems, there is a lot of responsibility for the reader to comprehend the drawings, and as a 'drawer' I have to assume a certain level of competence with the person reading them. Right? Certainly I will be including a page or more of notes on the construction of the engine, and the methods I used for setup, so this will help a bit.

Kel

I should note that this is not my first rodeo. I have a set of plans in the downloads section of a vertical steam engine named "Kelly's #1" So if any body wants to see my work, it is here.

http://www.homemodelenginemachinist.com/index.php?action=tpmod;dl=item262
 
I do my cad work upstairs, and machining downstairs. I usually completely forget all the dimensions in the ensuing trip, so I catch a lot of my own missing dimensions. ::)

As a general rule, parts to be made in the lathe are dimensioned in datum format, and non symmetrical or milled parts are usually dimensioned off the edges I use for edge finding. Its rather unavoidable to dimension parts based on your own machining preferences.
 
The reason dimensions shouldn't be stacked is because they could cause a tolerance stackup. If you had 4 successive dimensions and they all had +-.002 tolerance then by the time you got to the last dimension you could theoretically be .008 out of position.
It's not that someone would machine it this way it's just that if you were making a part for someone and they gave you a drawing dimensioned this way you could realistically give them the finished part and it would be within the drawing tolerance. You have to pick and choose which dimensions you stack.
gbritnell
 
Thanks George. I think I can get rid of the stacking if I make a few pages for the block. I am thinking about a FRONT-TOP-RIGHT for one page, and REAR-BOTTOM-LEFT views for another. Then a third page with detailed diagrams. Since this engine is so small I can fit all three views in scale on an 11.5 x 8 piece of paper. Some views will have to be exploded to show detail however. The problem with doing that is I have to manually correct the dimensions. I have not found a scale type option for this in my Solid Edge program.

Kel
 
kcmillin said:
Is is OK to have multiple drawings of the same plane? Sometimes I can't fit everything on one drawing, Like the hole locations for screws. Would two pages for the same part be OK? I will more than likely be making detailed diagrams of certain features, and this will take up precious space on the page.

IMHO yes, just call them Detail of......

Also, I am not sure the terminology, but how about 'Stacking' dimensions. Lets say one feature is 1" away from the edge, then the next feature is .5" away from that. Or would I have to make the second dimension 1.5"?

They are called continuous dimensions and from above 1=1" 2=0.5" etc. If you made 2=1.5" then you are back to datum measuring.

Hope this helps

Best Regards
Bob

 

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