Maudslay Model oscillating steam engine

Home Model Engine Machinist Forum

Help Support Home Model Engine Machinist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

cfellows

Well-Known Member
Project of the Month Winner
Joined
Aug 25, 2007
Messages
3,890
Reaction score
715
Here's a video of my completed Maudslay oscillating steam engine.



Lapping the rotary valve to valve block took fixed the last of the air leaks, so now the exhaust is about the only air that is audible.

Chuck
 
Nice smoothly running unusual engine .
Did you cast frame for this engine ?
Thank you
 
Thanks. The frame was assembled from individual parts. The feet, circle patterned brass insert, and top bridge connector were CNC cut. The sides of each frame are 1/4" brass tubing. All the frame parts were soldered together and fastened to the brass base plate with screws from the bottom.
 
Chuck,

That's very nice. It reverses so nicely and runs at a nice speed.

I also like the choices of materials.

Thank you for posting the build and the result.

--ShopShoe
 
Thanks for showing the engine. Very nice.
 
Thanks, Chuck. I first saw a small sketch of this engine in a model steam engine book I bought at the Kewbridge museum in London probably 30 years ago.

https://www.homemodelenginemachinist.com/threads/henry-maudslay-steam-engine.1109/

For many years I looked for other examples of the engine on the internet without success. Then, a couple of years ago I found a picture of a model which had been built many years ago.

https://www.bonhams.com/auctions/23024/lot/79/

With a 15 inch flywheel, it was about twice as big as mine and sold at auction for some $35,000. Some years ago I had created some drawings of the engine, not knowing any of the dimensions, but, by studying the relationships of the parts to each other, was able to get a close approximation. Then, several months ago I found a picture of a single cylinder model of the same engine.

https://www.gracesguide.co.uk/File:JD_2016_J_Spiller.jpg

With my mill/drill converted to CNC, I decided I could probably pull off the single cylinder version. In the model pictured, the cylinder and crank are mounted outside the frame. I changed the design of mine to be inside the frame. Fortunately, I had cast iron flywheel that was only a little too big and much too thick in cross section, so I thinned out the rim on my lathe and thinned out the spokes on my CNC mill. I also used CNC to cut the circle design brass insert, the feet, and the brass bridge part that supports the crankshaft. The frame sides were assembled from some 12 - 15 parts soft soldered together.

I never knew for sure how the valve mechanism was supposed to work, but came up with my own design which is probably close. The original drawing and models I found used an eccentric to supplement the cylinder motion, but I was able to design the stroke such that the cylinder motion alone was able to turn the valve enough without the eccentric.
 
Last edited:
Thanks for replying, Chuck. I was also in London many years ago, guided by my my English wife, while I was stationed in the UK with the Air Force.
Wish I'd paid more attention to the various engines on display back then.
 
Here's a video of my completed Maudslay oscillating steam engine.



Lapping the rotary valve to valve block took fixed the last of the air leaks, so now the exhaust is about the only air that is audible.

Chuck

Hi Chuck: Liked you oscillator engine design. Did u design or acquire set of plans? If acquired where was the source?
Thanks.
Bob E.
 
Thanks, Chuck. I first saw a small sketch of this engine in a model steam engine book I bought at the Kewbridge museum in London probably 30 years ago.

https://www.homemodelenginemachinist.com/threads/henry-maudslay-steam-engine.1109/

For many years I looked for other examples of the engine on the internet without success. Then, a couple of years ago I found a picture of a model which had been built many years ago.

https://www.bonhams.com/auctions/23024/lot/79/

With a 15 inch flywheel, it was about twice as big as mine and sold at auction for some $35,000. Some years ago I had created some drawings of the engine, not knowing any of the dimensions, but, by studying the relationships of the parts to each other, was able to get a close approximation. Then, several months ago I found a picture of a single cylinder model of the same engine.

https://www.gracesguide.co.uk/File:JD_2016_J_Spiller.jpg

With my mill/drill converted to CNC, I decided I could probably pull off the single cylinder version. In the model pictured, the cylinder and crank are mounted outside the frame. I changed the design of mine to be inside the frame. Fortunately, I had cast iron flywheel that was only a little too big and much too thick in cross section, so I thinned out the rim on my lathe and thinned out the spokes on my CNC mill. I also used CNC to cut the circle design brass insert, the feet, and the brass bridge part that supports the crankshaft. The frame sides were assembled from some 12 - 15 parts soft soldered together.

I never knew for sure how the valve mechanism was supposed to work, but came up with my own design which is probably close. The original drawing and models I found used an eccentric to supplement the cylinder motion, but I was able to design the stroke such that the cylinder motion alone was able to turn the valve enough without the eccentric.
Would like to see a close up or a sketch of the valving.
 
Sorry to say but Chuck is no longer with us. There is a comple Set of drawings in the file section.
The valve has both longitudinal and horizontal grooves to direct the steam and exhaust.
gbritnell
 
Sorry to say but Chuck is no longer with us. There is a comple Set of drawings in the file section.
The valve has both longitudinal and horizontal grooves to direct the steam and exhaust.
gbritnell
Sorry, I didn't know! I've never accessed the file system, can you please direct me?
 

Latest posts

Back
Top