Dolbeer Steam Donkey (Les Proper Design)

Started by Rledoux313 · 8 replies · 1,260 views

Rledoux313
31 Aug 2026, 00:30
Tonight I was able to get my steam donkey project to successfully run on steam!  :cartwheel:

I’ve been working on and off for almost 2 years on this, and have learned much more than I could have hoped for! The plans for this can be found in LSOR 2018 issue 3/4/5, those issues are in the digital library on village press and can be read if you have a subscription.

Here is a video, and some photos. The eagle eyed among you may notice that the photos show the connecting rod attached to the crank with an eccentric, while the video has a crank pin. When I was building the engine and running it on air I bent the crank rod, likely due to the wrong timing and too much air. This caused me to go the route of the eccentric so I could have the third crank bearing. After having trouble getting it to run I got in touch with Les and he advised changing that to a crank pin. That change, along with denatured alcohol in the fuel pan instead of sterno gel was enough to get it running.


https://youtu.be/V-wdUCY6A44?is=bS50MqR-ylqva_jlYouTube video
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crueby
Reply #1 · 31 Aug 2026, 00:34
Quote from: Rledoux313Tonight I was able to get my steam donkey project to successfully run on steam!  :cartwheel:

I’ve been working on and off for almost 2 years on this, and have learned much more than I could have hoped for! The plans for this can be found in LSOR 2018 issue 3/4/5, those issues are in the digital library on village press and can be read if you have a subscription.

Here is a video, and some photos. The eagle eyed among you may notice that the photos show the connecting rod attached to the crank with an eccentric, while the video has a crank pin. When I was building the engine and running it on air I bent the crank rod, likely due to the wrong timing and too much air. This caused me to go the route of the eccentric so I could have the third crank bearing. After having trouble getting it to run I got in touch with Les and he advised changing that to a crank pin. That change, along with denatured alcohol in the fuel pan instead of sterno gel was enough to get it running.


YouTube video

Excellent!!  Great work, runs very well.  :ThumbsUp: :ThumbsUp:


Whats the burner? Alcohol?
Zephyrin
Reply #2 · 31 Aug 2026, 07:14
nice little model, congratulations, and did you also make the crown gear under the large horizontal flywheel ? I'm looking for a way to cut gears like that.
Last edit: 31 Aug 2026, 07:18 by Zephyrin
Rledoux313
Reply #5 · 31 Aug 2026, 11:57
Quote from: crueby
Quote from: Rledoux313Tonight I was able to get my steam donkey project to successfully run on steam!  :cartwheel:

I’ve been working on and off for almost 2 years on this, and have learned much more than I could have hoped for! The plans for this can be found in LSOR 2018 issue 3/4/5, those issues are in the digital library on village press and can be read if you have a subscription.

Here is a video, and some photos. The eagle eyed among you may notice that the photos show the connecting rod attached to the crank with an eccentric, while the video has a crank pin. When I was building the engine and running it on air I bent the crank rod, likely due to the wrong timing and too much air. This caused me to go the route of the eccentric so I could have the third crank bearing. After having trouble getting it to run I got in touch with Les and he advised changing that to a crank pin. That change, along with denatured alcohol in the fuel pan instead of sterno gel was enough to get it running.


YouTube video

Excellent!!  Great work, runs very well.  :ThumbsUp: :ThumbsUp:


Whats the burner? Alcohol?


Yes, I am using denatured alcohol in the burner.
Rledoux313
Reply #6 · 31 Aug 2026, 11:58
Quote from: Zephyrinnice little model, congratulations, and did you also make the crown gear under the large horizontal flywheel ? I'm looking for a way to cut gears like that.


Thanks! The gears are out of a fishing reel.

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