University of Maine's BSMET Steam Engine

[taiden]

Greetings all,

I am a student in the Mechanical Engineering Technology program at the University of Maine. As part of this program, we draw and build a steam engine. The plans are given to us during lecture. We use these plans to familiarize ourselves with CAD (Solid Edge) and it's attached drafting tools.

After our blueprints are signed off by our professor, we are trained on basic machining principles using the steam engine as our project. We are split into teams of five and we assign parts to each member.

At the end of the semester, we race our completed engines by supplying them with air flow via the shop's air system. We run them at no load and record the maximum RPM achieved using a tachometer on the flywheel.

Feel free to use these plans for your own projects. The drawings have been approved, but we are now beginning the build. I will try to keep the plans up to date if we find any errors. Please note that the file is property of University of Maine's Mechanical Engineering Technology department, any reproduction for sale is strictly prohibited.

THE PLANS CAN BE DOWNLOADED HERE OR HERE

[ame]http://www.youtube.com/watch?v=Pi-OcbBU6Dw[/ame]

[ame]http://www.youtube.com/watch?v=OUYSbetbuh0[/ame]

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View attachment UMO-BSMET-Steam-Engine-2013.pdf

 

[lennardhme]

Nice engine & thanks for the plans.
Are you testing max. revs to evaluate quality of build ?
If so, may I suggest a better test would be how slow will it rev - much more interesting.
Leonard

 

[taiden]

Hi Leonard,

The no load max revs test I think just happens to be tradition for the college. It was discussed in another thread to use a baker fan and I completely agree.

The slowest rev test is also a really good idea. I feel it would reward very well timed engines.

What usually happens is the gearheads open theirs up and do port and polish jobs to try to get the best speeds.

 

[lennardhme]

Hi,
yes, using a baker fan would be a good idea. Max. no load revs might not be too good for the engine.
Your response also raised another question in my mind - not sure that port & polishing would help with improved revs in an engine with an applied pressure [air or steam] compared to an IC engine where it certainly would.
Bit out of my area of expertise. Maybe someone could help with an answer ?
Certainly not common in steam engines that I know of.
cheers,
Leonard

 

[taiden]

In my experience, anecdotal and actual, it certainly does. You reduce flow restrictions and mechanical resistance and the reduced losses will result in a higher operating speed.

 

[RonGinger]

Leonard is it your class that is working to finish up the Lombard Log Hauler restoration? I understand they hope to run it for graduation, after many years of work.

 

[kvom]

A few thoughts from looking at the plans and photos.

1) Getting the columns dead straight and equal length on the base can ensure that everything is lined up.

2) Pay attention to the bearings/pins that attach the conrod and the eccentric. Lots of chance for friction there. A little graphite powder during the run would be useful.

3) Polish the eccentric strap and eccentric.

 

[lennardhme]

No, not me Ronginger. Bit past the educational stage - I just learn things.
Leonard

 

[barnesrickw]

Leonard is right about the porting and polishing. At this scale the forced air on the inlet should not experience much pressure drop in the short distance the air has to travel. There is also this idea by Bernoulli that says a fluid to fluid contact has a lower coefficient of friction, so better flow. Now a larger orifice would make a difference, especially on the exhaust side where it takes the energy of your engine to remove the air from the cylinder.

 

[taiden]

Leonard is it your class that is working to finish up the Lombard Log Hauler restoration? I understand they hope to run it for graduation, after many years of work.

The Lombard Log Hauler is being handled by the BSMET class above me. Really interesting project for sure. There are a few videos on YouTube of the work they are doing.

 

[RonGinger]

opps, sorry I got the names confused.

The Lombard is a great machine. I drove the one at Owls Head a few times, see [ame]http://www.youtube.com/watch?v=hPJkkH3ELAA[/ame] That machine is now at Leonards Mills along with the one being finished by the U Maine class.

Brian Barker, the guy behind the Mach3 CNC software did a lot of the early work on the Lombard that U Maine is finishing.

 

[marcduper]

Great videos! I am from the class of 2003. I worked the log lauler, great times. If you see Herb, tell him Marc says hi. Good luck.

Marc