My version of SandyC's 3" vertical boiler

[doubletop]

Andy

Now I've got the "watering can" producing steam I must go back and do some more tests with the pumice version. At least I didn't try it with green stone. That would have been problematic and I'm not talking technically.....

Have you done the capacity calcs, and had any luck with finding yourself a piece of copper tube?

 

[ss2fly]

No I haven't yet sorry, been busy fitting the Motard wheels to the KTM, sorting the workshop, organising the space for my South Bend lathe I just aquiried....... finding room for a mill that is in the pipeline etc.... so the boiler has gone on the "back burner" so to speak....

I am still fooling around on the old 1909 Drummond Roundbed Lathe I have, making bearing spacers and collars etc fot the wheel conversion on my KTM so all is not lost..

I really need to finish some of my existing projects before I start new ones.

Andy

 

[bearcar1]

.....all shapes and sizes... (stuff the IWI....)

Hmmm, how do they taste? Are they any good on the grill? (barbie) LoL!

DT, well done man, That boiler will look like a million bucks when you get it all together, polished up and mounted. It'll be a show stopper.

BC1
Jim

 

[doubletop]

.......... been busy fitting the Motard wheels to the KTM, sorting the workshop, organising the space for my South Bend lathe I just aquiried....... finding room for a mill that is in the pipeline etc.... so the boiler has gone on the "back burner" so to speak....

I am still fooling around on the old 1909 Drummond Roundbed Lathe I have, making bearing spacers and collars etc fot the wheel conversion on my KTM so all is not lost..


Andy

I'd have thought that you'd have enough on your plate without adding a boiler right now. I'm looking at buying a mill but have deliberately avoided that until I get this boiler finished, otherwise I never will. As a newbie I've set myself the goal of doing something sensible with what I've got before spending money on new toys. Hence the wobbler and now the boiler. Once the wobbler runs under its own steam the order for the mill goes in. I've already got financial approval from head office.

DT, well done man, That boiler will look like a million bucks when you get it all together, polished up and mounted. It'll be a show stopper.

BC1
Jim

Thanks; It is looking good right now I've cleaned it up a bit and added the fittings so I can show off at the local model engineering club tonight. http://steammachine.com/hvmes/

 

[doubletop]

I had not run the engine on the boiler as I wanted to make a reversing valve for the engine, and until I’d done that I didn’t want to waste tubing and nipples on a temporary plumbing of the steam pipes. I got stuck into the reversing valve first thing Saturday and had it finished by the afternoon.

Its pretty basic and just allows the inlet and exhaust to be swapped on the two ports to the engine.

The port plate

Milling the steamways in the lathe. I don’t have a rotary table and dividing plate so a 6BA screw through the job and into a convenient 6BA hole taped into the vertical slide and diestock to rotate the piece did the job.

The parts ready to go

The assembled reversing valve.

Now time to put it all together on the base and get it plumbed up. I was looking around for something to protect the base from the heat of the burner. We have steel roofs in NZ and in the junk box I found a set of samples for Colour Steel roofing left over from having the house renovated. The Zincalume sheet was perfect; it only required two holes to line up with the boiler base. It was even the right size and already had the corners rounded.

All that was required was to steam it up and see how it went. Although it ran it was pretty unspectacular.

[ame=http://www.youtube.com/watch?v=exkydCEOk8o]http://www.youtube.com/watch?v=exkydCEOk8o[/ame]

Issues are:

1) Leaking safety valve, not holding pressure, even the propriety one fails to hold pressure above 25psi. I'll start by searching for the thread on testing and setting safety valves.

2) Not enough heat from the burner to be able to maintain steam pressure. This is the "holes" version, I've not tried the pumice version. Also if I crank it up to high the gas jet ignites. I was told that it is best to use stainless rather than copper for the burner, as it doesn't hold the heat and warm up the gas, so making it susceptible to flash over.

3) Leaking joints. And one port on the engine leaks too much to be able to use it as the input port. So I'll just have to work through them.

The consequence of these points it only runs briefly, and only in one direction.

I’ll work on these points and I still need to do the cladding, but I’d say that’s about as far as this post needs to go for now I'll close it here

So

Thanks to Firebird for encouraging me to write this all up. Doing it made me keep going and make sure I did the best job I could.

Thanks to everybody who gave me tips and advice on the way, Firebird and Bogstandard come to mind in particular, but there were plenty of others as well.

And last but not least thanks to everybody else whose posts encouraged me to keep going

That’s all folks……….. at least until the next time.

 

[Deanofid]

I do hope you'll show us more when you get the little diddles sorted out, DT. It looks good, and it steams up to run your engine. Don't forget us!

Dean

 

[zeeprogrammer]

Although it ran it was pretty unspectacular.

Not from my perspective. That was spectacular and deserves congratulations.
It's a great looking boiler and display.
I've enjoyed this thread.
Thanks for sharing.

 

[steamer]

Sounds like normal debug to me. We've all had some to do

Great video and congratulations on a job well done!

Dave

 

[4156df]

Very nice engine/boiler set-up. I second the request for another video when you finish your final de-bugging. Thanks for posting.
Dennis

 

[doubletop]

Very nice engine/boiler set-up. I second the request for another video when you finish your final de-bugging. Thanks for posting.

I do promise to post a final video when the engine runs well.

In the meantime I've also just had another run through this posting and now realize some of the icons on this forum who have taken the time to comment on my efforts. Some of you guys produce some outstanding stuff and there are some gems behind your postings. Only today I noticed this link in Deanofids footnote http://www.deansphotographica.com/machining/projects/projects.html

Its well worth a detour........

 

[firebird]

Well done DT, nice job :bow: :bow: :bow:

Cheers

Rich

 

[Deanofid]

Very kind of you, DT. Thank you.

I'm sure any more pics or videos you would like to put up will be well received. I always enjoy a boiler build, and this has been a darn good one!

Dean

 

[doubletop]

I've had some success with the safety valve and made a new burner to get some more heat into the boiler. I can now get the pressure up to about 45psi. So here's the latest.


http://www.youtube.com/watch?v=DNFx0TZUD54

Once face of the port isn't sitting properly so the steam is escaping from there and not going up the exhaust pipe. You can condensed water dribbling down the face of the engine.

Of course cladding the boiler and lagging the pipes will help with the heat retention. To (mis)quote somebody "These things are heat engines not steam engines"

 

[Blogwitch]

DT,

Usually, where people go wrong when running an oscillator (wobbler) on steam is that they feed too high a pressure to the engine, and the spring and port faces on the engine act like another low pressure safety valve and release steam to atmosphere.

The cure isn't to tighten up the port face spring tension, as most people attempt to do, as all that does is to increase the friction of the engine, and so requires even more steam to turn it over, so the boiler very quickly can't keep up with the engine. A catch 22 situation can occur if you do that.

You know that the engine will turn over freely, and run quite merrily on a low volume and pressure, so the easiest way is to put a small steam **** valve in the line from the boiler to the engine, before the control valve, so that you can easily control the maximum flow to the engine.

By fine tuning that steam valve, you can get it set so that the engine only gets the steam it really requires, no more, no less.

You should end up with a well running, very smooth engine, which stays a lot cleaner, with the added bonus of the boiler should be able to easily keep up with the supply of steam to the engine, in fact, usually you will need to turn the burner down as the boiler will most probably be producing more steam than is really required.

This is an extract from the instructions I used to send out with my own built engines.

I advocate the use of TWO steam shutoff/control valves, one near or on the boiler and another just before the engine lubricator. The one on the boiler should be used as a shutoff valve, it will allow you to build up steam without letting any wet condensate to the engine and also use as a shutoff to the engine to allow you to top up the lubricator without turning off the boiler. The second one near to the engine is used as a steam regulator, to allow the correct quantity of steam to the engine, and once set is never altered. How many times have you seen a model steam engine ‘blowing’ steam from all its port faces, there is no need for this, adjust the steam control valve until the engine runs smoothly with no ‘blowout’, you will use a lot less fuel and water, the engine won't get as dirty. Many people think you will get more power out of the engine, you won't because it is running inefficiently.

At the bottom in the two pics, of two of my customers installations, it shows the valve I am on about. What they don't show are the control valves also on the boiler, as mentioned in the text extract.

Hope this helps.


Bogs

 

[doubletop]

Bogs

Its as exactly as you describe it, and you may notice I have tried increasing the port face spring tension by the inclusion of a length of 1/4" copper pipe!! The steam valve I am using doesn't provide much control being just about on or off and nothing in between, but I did find it in the junk box.

Your suggestion gives me an idea and I may look at modifying the port switch I have made and include an adjustable restrictor on the inlet port. Maybe just by using an Allen head screw turned to a taper. I'll look into it.

I do still have an issue with the way port faces align which I also need to look into. Currently it doesn't allow me to use the other port as an inlet as steam pressure just dumps.

Once again thanks for your advice. I have no idea what stage of my build would be at if it wasn't for this forum, probably "junk" and I'd be returning to electronics.

Pete

 

[Deanofid]

Thanks for the new video, Pete!

Your outfit sure looks good from where I'm sitting. You might need to do a light face job on the mating surfaces of the cylinder and main ports, keeping them square to the cylinder mounting shaft. There are always a couple of details to getting all the parts happy with one another, but it looks like you're close to having it licked.

Bogs' advice is right on about the spring pressure. Sometimes that detail seems counter-intuitive, but it makes a difference.

Keep at it. I'd be happy to see yet another video of this neat steam plant. Very nice, I think.

Dean

 

[doubletop]

The cylinder spindle wasn't quite square, one of my early days efforts, I've removed the 3mm spindle and drilled and tapped for 4BA and replaced. As Bogs suggested slacking off the spring pressure and lowering the output pressure of the steam and it runs a lot longer now.

Current issues are:

1) The steam exhaust is fed to the flue. the first steam condenses on the way back to the flue and a the subsequent glob of water then puts out the burner! Current remedy remove the exhaust pipe from the flue.

2) The steam removes the lubrication from the engine so it sizes up after a while. Current remedy, include some lube holes here and there. change from 3 in 1 oil as its probably too light. Consider an oiler

3) minor leaks here and there in the pipework. Remedy strip down and fix.

So it all in bits, right now, and pipework in the pickle ready for re soldering.

 

[Blogwitch]

Just to clear up a couple of your problems Pete.

1) If you had a vertical firetube boiler rather than a straight thru chimney, that wouldn't be a problem, but as you know, the straight down chimney will cause you a problem. But also there is a safety issue to contend with here, when first firing up the boiler and feeding steam to the engine, you must ensure no-one is near to the funnel outlet. I have seen plumes of steam and scalding hot water rising to about 10ft in some cases. But to get back to your problem of the burner going out, just feed the tube onto the outside of the chimney rather than inside, it gives exactly the same effect when running.

2) You really do need to fit an inline lubricator, and use the correct STEAM OIL. Normal oil is absolutely no use for running a steam engine on steam.

http://www.roundhouse-eng.com/faqs.htm#14

Go down the page on here, and it shows everything you need to make a working displacement lubricator. You can make either the inline or offset, they both work as well as each other. You could even modify it a bit and put a drain in the bottom, to save having to use a syringe to get the water out.

http://modelsteam.myfreeforum.org/ftopic7859-0-asc-15.php

3) Only you can do that


Bogs

 

[doubletop]

Once again thanks for the advice. I had come to the conclusion to run the exhaust away from the flue and had already removed the pipe and re-routed outside the flue. What I was considering was running the exhaust inside the flue but it being the full length up to the top of the flue, however I wasn't aware of the potential for jets of scalding water.

Again I had also realized I needed a lubricator (I'd called it an oiler). I know Firebird had made one but was skipping that step to getting it running. Thanks for the links, it needs to be next on the to-do list. They don't look to be too difficult to run up so it could be done soon.The 3 in 1 was the easiest thing to grab once I had steam up and realized the problem I'll try and source steam oil my local MES should be able to help. In the meantime I'll try some mountain bike oil its has a high water resistance and as I don't have a super heater carbonizing won't be a problem.

 

[doubletop]

I’ve not done an update on this for a few days as I’ve been a bit distracted. On Wednesday I decided that I would buy the X3 mill I’d been promising myself. So it was ordered on Thursday, delivered from Auckland on Friday (650kms away), stripped, cleaned, reassembled, installed and running by Saturday night. They do cover those things in a lot of gunk!

Anyway back to this; I have followed Bog’s advice and made an oiler and a restrictor for my setup.

The oiler is pretty much to Bogs drawing, but I made an inline version and used copper tube rather than brass to keep it simple, but also included a drain plug

For the restrictor I modified the reversing valve I had made previously, by making a longer coupler for the inlet port. The coupler is drilled 2mm and a 3mm grub screw used as the valve. The tapping for the grub screw goes past 2mm bore so the steam can be completely shut off. The grub screw is installed with Loctite thread locker that makes it steam tight and allows initial adjustment.

By the way, the ball on the end of the reversing lever is a 1/4" torlon ball I had lying around and drilled 3mm part way through and a push fit on the 3mm lever.

I’ve had it all together and running and both the oiler and restrictor work fine. I’ll do a new video once I’ve got everything cleaned up following making of new steam pipes. Currently it’s all stripped down again and in the pickle.

Pete