# Pug



## SignalFailure (Jun 3, 2009)

Nearing completion of the construction phase of this little piston-valve controlled engine. Here it is held in a vice powered by a foot-pump - especially pleasing as I haven't even made a gland nut or lapped the valve face where it meets the cylinder yet (you can see gaps between the two at present!)

Outline plans here, final detailed (metric) plans to follow... http://www.homemodelenginemachinist.com/index.php?topic=4870.0

So far I'm pretty pleased with this one as I designed it from scratch and built it from whatever was to hand (steel, brass and bronze) ;D As the stroke is short it seems ok without any crosshead guide/support. The only real modification I'd make is to use a split eccentric strap (or at least re-arrange the standards) to make setting the timing easier.

[youtube=425,350]Whka7JQMEsY[/youtube]


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## SignalFailure (Jun 5, 2009)

Smoothed it out a bit, now runs reasonably well on a couple of PSI from the aquarium pump. Just need to make all those tedious screws and a stuffing box (for show!)...

[youtube=425,350]7snUNQGQWR0[/youtube]


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## bearcar1 (Jun 5, 2009)

Man I do like those slide valve type engines! Especially when they go down to just a tick. Well done job. :bow: I have DL'd your drawings and may have a go at a 'Pug' one of these days, it appears to be relatively straight forward and the short coupling makes the job even easier. :big:

BC1
Jim


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## SignalFailure (Jun 6, 2009)

Cheers Jim.

Couldn't resist hooking it up to my test boiler for a blast 

[youtube=425,344]XlwhpwRWlM8[/youtube]


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## bearcar1 (Jun 6, 2009)

Paul, that sounds real good! ;D Something about the ever present hiss of steam power to get one going in the morning. I may have a go at 'bashing' your design but I really do enjoy "The Pug".
It reminds me of a "Little Gem Dandy" with out a cross head in some ways. (by the way, you lost a head screw Rof} )

BC1
Jim


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## SignalFailure (Jun 10, 2009)

Seeing as how it actually runs I thought I'd better tart it up just a little ;D

Made a new con-rod and replaced the ugly grub-screw that was sittin on the eccentric with an oil cup. Turning 6mm rod down to 2mm between the con-rod ends was a bit fiddly - had to grind away part of my left/right handed HSS tools to fit in the gap.

Might put some holes in the flywheel and eccentric strap to reduce the mass.

Sheesh, this should be in 'work in progress'...sorry! 







Note to self - must make a better job of hiding the errant holes


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## bearcar1 (Jun 10, 2009)

That is areally cool little engine. I also compliment you on your selection for a photographic backround as well. ;D I will have to have a go at one of these when I get the chance.

BC1
Jim


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## SignalFailure (Jun 13, 2009)

I made two different screw-in connectors for running on air or steam and a displacement lubricator for use on the latter. Here it is hooked up...






Really must do something with that flywheel and saw off the excess shaft (so useful for tweeking the engine or connecting to power when running in though!)


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## rake60 (Jun 13, 2009)

Great work Paul! :bow:

As for those plugged holes; If nothing ever needed repaired
there wouldn't be much of a demand for qualified machinists.


Rick


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## Paolo (Jun 14, 2009)

Nice job Paul on that nice engine....!!! :bow: :bow: :bow:
Cheers Paolo


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## kustomkb (Jun 18, 2009)

Nice job!

I have an aquarium pump that really needs an engine.

Thanks.

Kevin.


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## Maryak (Jun 18, 2009)

Paul,

Very nice little engine :bow: and another for running it on steam. :bow:

Best Regards
Bob


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## SignalFailure (Jun 18, 2009)

Thanks for the kind words people.

Bob, maybe there should be a separate forum section for those with a specific interest in steam? I know I've got plenty of questions I'd like to put in there! ;D


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## kustomkb (Jun 23, 2009)

Thanks for sharing your design,

Here is a computer model of it;

[ame]http://www.youtube.com/watch?v=32GGfCqh-a4[/ame]


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## SignalFailure (Jun 23, 2009)

Kevin, that's fantastic!! :bow: :bow: :bow:

It really shows off the simplicity and small number of parts to great effect especially the exploded view.

Many thanks for taking the time and trouble to do that, I feel really chuffed (haha) now!

Paul.


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## gilessim (Jun 23, 2009)

Great work there Paul, I wish I had the time!!

Giles


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