A Simple Uniflow Engine

[gary.a.ayres]

Yes!

Cheers, Chris!

 

[gary.a.ayres]

The engine itself is finished:




























Vital statistics (as seen here) -

Overall length:     450 mm / 17 5/8 inches

Frame width:     145 mm / 5 ¾ inches

Overall width (including crankshaft):     300 mm / 11 ¾ inches

Height:     203 mm / 8 inches

Bore:     35.7 mm / 1 7/16 inches

Stroke:     40 mm / 1 5/8 inches

Flywheel diameter:     157 mm / 6 3/16 inches

Large pulley (round belt) diameter:     112 mm / 4 7/16 inches

Small pulley (flat belt) diameter:     51 mm / 2 inches

Weight:     12.9 kg / 28.4 lbs


Materials -

Frame (including base):     aluminium

Cylinder:     cast iron

Piston:     cast iron

Crosshead:     cast iron

Connecting rod:     bronze

Big end:     cast iron

Crankshaft:     steel

Main bearings:     bronze

Flywheel:     steel

Large pulley:     brass

Small pulley:     aluminium

Bushes and collars: bronze and cast iron

Fixings:     stainless steel

All that remains is to finish the base, which is made of oak.

I got rid of my big old cheap table saw a couple of years ago as it was taking up too much room. Nowadays I set up an improvised arrangement featuring my Evolution Rage circular saw clamped upside down in a workmate with a joinery clamp holding the trigger in the ‘on’ position. I am not advocating this practice, just describing what I do!



The base was cut to its basic shape and worked with rasps, a planer, a scraper and sandpaper:



There’s still quite a bit of work in this as it’s still quite rough. Definitely worth putting some time into though I reckon...

[propforward]

Absolutely superb Gary! Really unique engine - great to see the finished article. Looking forward to seeing the engine on its base.

[gary.a.ayres]

Thank you Stuart! Very kind of you, as always.

 

[gary.a.ayres]

 The aluminium base plate of the engine was used to transfer hole positions on to the top of the wooden base:



These were brought to size using various bits in the drill press:





Four holes were then drilled in the underside to take threaded inserts for the feet:





The gaps in the oak base where the two pieces of wood joined were then filled, and a fair amount of sanding was done. The wood was then treated with Danish Oil (natural, not coloured) - a total of six coats to protect it from oil, steam and water. The way that the first application of Danish Oil dramatically transforms the look of the wood is always a favourite moment of mine:



The engine was then fixed to the wooden base with wood screws which passed through clearance holes in the frame side support bars and the base plate. Before doing so, I used a generous amount of silicone sealant round all the edges and screw holes to prevent water from seeping in between the engine and the wooden base.

Et voila! This engine is done:









And finally, a short video. I deliberately made the base quite massive thinking that this - in combination with the orange rubber feet - would keep it stable when running. Not a bit of it, as you will see from the video. This thing is a bucking bronco, mainly due to that long cast iron piston. When it's in use, the feet will be removed and the engine will be bolted to my bench to hold it steady. The feet can go back on when it's on display.

<a href="https://www.youtube.com/watch?v=071Zh0OVfcU" target="_blank">http://www.youtube.com/watch?v=071Zh0OVfcU</a>

I'll come back to this thread in the fullness of time when this engine is running on steam... 

Many thanks to you all for the help, advice and encouragement that so many of you have given me along the way with this build.

And now on to the next one...

gary

[RReid]

That looks really great, Gary! A fine runner, and it sounds good too! Congratulations! 

[crueby]

Wonderful!  Sounds great, looks great, runs well. Part of the movement was likely the uneven surface. Just wedge a shop gnome under that high corner...


 

[propforward]

Brilliant result Gary!

 

[MJM460]

Excellent result Gary.  Great to see it come to life.

Those flywheels don’t look bad at all.  When we were talking about flywheels, I thought you were thinking of something much bigger.  Interesting strobe effects with the fixing screws and the camera.

Now to think of the next one.

MJM460

[Jasonb]

Good to see it finished and running.

Adjusting the feet so all 4 are in contact with what's under it will help with the moving about but it it is still a bit lively you could think about balance weights on the crank or taking some metal out of one side of the flywheel rim.

[Zephyrin]

nice to see your engine running that well... congratulations !
adding a counterweight on the flywheel would help with the jumping, something around the weight of the piston plus the conrod.

[ShopShoe]

Congratulations.

A somewhat different design, but I like it.

It does sound nice.

I'll be watching for what's next.

Thank You for posting

ShopShoe

[gary.a.ayres]

Many thanks all: Ron, Chris, Stuart, MJM, Jason, Zephyrin and Shopshoe.

@ Chris - good suggestion. However,  it appears that my shop gnomes read your post before I did, because when I went out to my shop this morning they had already called out NUGGETS (the National Union of Gnomes, Goblins, Elves, Trolls and Sprites). The rep met me at my shop door, his arms folded in determination, and the upshot of the ensuing discussions was that I agreed not to use any of the workers as living shims or packing, on the basis that the gnomes would ensure that the engine's feet are properly adjusted and locked at all times. It was also agreed that should this measure prove to be ineffective, a delegation of the workforce will remove the feet and bolt the engine on to my bench for further stability testing.

My view is that this was a satisfactory outcome. The question of balancing of the flywheel (as suggested by Jason and Zephyrin) was not discussed at the meeting but this can always be revisited at a future date should it prove to be necessary.

[Dave Otto]

That's a really interesting design Gary, for the longest time I really had no idea where you were headed with this, and now I see that you had a plan the whole time.
Great project and great outcome, nicely done!

Dave

[crueby]

Many thanks all: Ron, Chris, Stuart, MJM, Jason, Zephyrin and Shopshoe.

@ Chris - good suggestion. However,  it appears that my shop gnomes read your post before I did, because when I went out to my shop this morning they had already called out NUGGETS (the National Union of Gnomes, Goblins, Elves, Trolls and Sprites). The rep met me at my shop door, his arms folded in determination, and the upshot of the ensuing discussions was that I agreed not to use any of the workers as living shims or packing, on the basis that the gnomes would ensure that the engine's feet are properly adjusted and locked at all times. It was also agreed that should this measure prove to be ineffective, a delegation of the workforce will remove the feet and bolt the engine on to my bench for further stability testing.

My view is that this was a satisfactory outcome. The question of balancing of the flywheel (as suggested by Jason and Zephyrin) was not discussed at the meeting but this can always be revisited at a future date should it prove to be necessary.