Elmer's Vauxhall Donkey Engine #49

[Inky Engines]

I've just completed this example of one of Elmer's less common engine builds, and I realised that it's the first engine that I've built that does anything more than turn the flywheel! The build is straightforward, and the performance perfect for providing feed water to the steam plant's 3" diameter boiler. The pump suffers from water hammer in operation, which makes the engine and steam plant sound a little noisy at times, but I understand that this is also a feature of the full size unit.

As an aside, I find that Sandy Campbell's 3" vertical boiler design will drive both Elmer's VR75 engine and the steam pump (mostly on bypass) on a continuous (or at least for 1 hour) basis, and this with a 1" diameter ceramic gas burner rather than 2" diameter as designed.

I'm thinking of Elmer's Radial #11 Engine next - with round cylinders as per common recent practice.

As always video and photograph below:

[ame]http://www.youtube.com/watch?v=KIfvSQBR5BA[/ame]

Note to author - must try to improve diamond knurling!

Kind regards

Geoff at Inky Engines

 

[cncjunior]

That is a nice looking pump! I wonder what would be the max. size boiler that this could feed and maintain water?

I have had a few knurls come out looking like yours myself. A shop teacher showed me a method that gets good results though I haven't had much opportunity to do it.

 

[Inky Engines]

Daniel

I suspect the restricting factor on use of this pump would be the operating pressure of the boiler, rather than its size. With the 3" boiler running steadily at about 20 psi the pump spends most of the time on bypass - it could certainly deliver a much greater volume of water to a larger boiler. The pump will supply feed water with a boiler pressure of 45 psi, but I haven't explored the upper limits.

Any tips on the knurling appreciated.

Kind regards

Geoff at Inky Engines

 

[cncjunior]

Hi Geoff,
Thanks for the reply. I imagine that as the boilers get larger and the operating pressure goes up then the pump will be able to compensate for the higher working pressure. In other words, higher boiler pressure = harder to pump in but due to higher pressure at water pump= easier to push water past the clack valve on the boiler. In my book of desires I want to build a 6" boiler of operating pressure in the range of 80 -90 psi. So I can check injectors.

On to knurling. One of my instructors who had retired and came in as a substitute said while the machine is in bull low rpm push the knurling tool into the work and keep pushing with the cross slide until you can't push any more then crank even more. engage the fastest feed possible (set before hand ) and run the knurl for the desired length. Use cutting oil. Now as you can imagine this is very hard on the lathe. I wouldn't recommend it unless you are at wits end. BTW this is for the style of knurling tool that pushes with two rollers as opposed to the two rollers that bite down 180 degrees apart (ie one on top the other on bottom).

Now the other method is much longer to explain. I am not sure if I have time before I go to work this morning. What I can do is get to it when I come home from work today.

Basically you push the knurling up to the work with spindle stopped and apply gentle pressure with the cross slide and roll the spindle back and forth by hand about 30 degrees worth until you get an imprint of the knurl. Then keep rolling back and forth gradually working around till the knurl from the top just about reaches the knurl pattern from the bottom roller. Keep working the pattern for a few rotations and at that point gently roll the spindle while watching until the knurl from the top gets to the bottom once again. Now keep rolling the spindle very gently past the knurl. The aim is to guide the roller back into its own previous indented pattern. Once the roller is tracking 100% in its own path then you can start the machine and engage both spindle and feed. Once again use cutting oil. I realize that just writing this that it is very verbose and is one of the reasons I was a bit hesitant to write it down. My apologies. I think that seeing it in person or on a video would be better though I haven't one.

So much for waiting till after work.

Not sure if what I have written makes sense.

Cheers,

Daniel

 

[Gerry Sweetland]

That is pretty cool that you make your model do work!
I like the way you made your video too.
Gerry

 

[vascon2196]

Another great looking Elmer's Engine!

If you have not already....it would be neat to see all of the Elmer's engines you have built! Maybe a slide show....

Great job!

 

[lennardhme]

Very nice looking engine. Its not in my list of elmers plans.
Can you give me a lead on where to find them?
thanks,
leonard

 

[gus]

Hi Geof,
Please advise source of plans. I am itching to build this engine. Could use it to transfer Chinese Herbal Tonic Wine.

Gus Teng

 

[deverett]

Gus

John Tom is your friend for Elmer's engines.
Have a look at http://www.john-tom.com/html/ElmersEngines.html
No.49 Vauxhall Donkey Pump

Good luck with the build.

Dave
The Emerald Isle

 

[Inky Engines]

Thank you all for your kind comments.

Gus, Leonard ... as Dave advises the plans are available at http://www.john-tom.com/html/ElmersEngines.html I'm fortunate enough to have acquired a copy of the Elmer's Engine book at a sensible price, but these are pretty difficult to get hold of now and the book in its entirety is downloadable from the john-tom site. Generally, the pdf copies on the john.tom site are more than adequate and obviously, I can't forward copies of the plans, but I would always be happy to look up on the originals anything that was unclear on the copies.

Chris ... this is the latest photograph I have of all the engines, but it doesn't include the VR75 engine or donkey pump shown as parts of the live steam plant on the latest video.

Perhaps I'll post a slideshow when I've built them all!



Kind regards

Geoff at Inky Engines

 

[lennardhme]

Many thanks - I'm a regular visitor to John-Toms, but as I said, missed this one
Have corrected that now.
cheers,
Leonard

 

[weez]

I have admired all your engines on here separately but I really like the picture of all of them together. Have you built any engines other than Elmer's engines? Do you really plan on making them all? I am currently on my fourth Elmer's engine and I plan to make at least five more of them.

 

[gus]

Gus

John Tom is your friend for Elmer's engines.
Have a look at http://www.john-tom.com/html/ElmersEngines.html
No.49 Vauxhall Donkey Pump

Good luck with the build.

Dave
The Emerald Isle

Hi Dave
Thanks.
Been craving to build this a toy to transfer water. Still trying to ramp up the level of confidence to build a 3" Boiler to run a slide valve d.a. engine to power this boiler feed pump.Problem is.Gus has too many hobbies and a long list of builds. Planning to make a Fishing Rod Wrapping Machine. Plans now being made mentaliy but encumbered by severe procrastination.

 

[vascon2196]

Thank you Geoff for posting that picture! I myself have a (very long term goal) of completing ALL of the Elmer's engines. I always enjoyed collecting things growing up and Elmer's collection of engines is one that will be the most difficult, but as you know its fun trying.

I only have 5 completed but that's okay...no rush and there is no customer on the other end demanding them!

Your engines look great...keep going. I wonder of anyone (besides Elmer) has finished all of them? Hmmmmmm......well your getting there.

 

[Inky Engines]

Weez .... the only engines I've ever built are those of Elmer Verburg, and these have all been completed during the last 2 years. I'm constantly tempted by the amazing engines designed, built and posted by others, but so far I have't succumb. I very much doubt that I'll build all Elmer's Engines, but I do seem to keep finding another one that interests me!

Chris ... I've now completed 13 different engines, a couple of which I've made twice, for a gift and to run on the live steam plant. There are a number of very prolific Elmer Engine builders out there, but I also wonder if anybody has completed them all?

Kind regards

Geoff at Inky Engines

 

[ronkh]

Very nice Geoff.
(All of them and thanks for showing).

Kind regards,

Ron