Engines > Your Own Design
1904 Whitehead Vertical Gas Engine
Jasonb:
I’m not sure when this engine first caught my eye but I have had this photo in my “Future Projects” folder for some time.
There is very little information to be found for Whiteheads or any of their engines. The “A-Z of British Stationary Engines” does have it listed with a copy of this illustration and a summary of the text.
I have been unable to find any views showing other sides of the engine and asking around on the Stationary Engine Groups, it appears they are very rare, the one in the photo is said to have been reconstructed from just a few remaining original parts and it is said there is another more original engine but that is not shown in public. After making a start I did find a short video but once again taken from the same position.
I made a start on the design by importing the image into Alibre and scaling it to suit 230mm flywheels which works out at just a bit larger than 1/3rd scale. There had been a few comments on the FB Groups that other may be interested in making one so I designed it with using castings for the flywheels and base in mind. This is the basic design with a few of the smaller details to be added as work progressed.
Starting with the patterns. To reduce the amount of cutting time on the CNC and also to get a more stable pattern the basic shape was glued up from strips of hardwood and stuck to a piece of MDF with a sheet of paper in the joint which makes it easy to remove from the MDF once complete.
The roughing cuts were done with a 6mm long reach flat ended cutter, 8mm DOC followed by a 1mm stepdown which leaves a contoured look.
Then a swap to a long reach 4mm 4-flute ball ended cutter using a 0.25mm stepdown refined the surface, part way through, then complete. This finish only requires a very light sand to have it ready to paint.
A quick blow with a chisel and the part is separated from the MDF base.
The flywheel was done in much the same way but as I did not have the Y travel each side had to be done in two halves, rotating the blank 180deg.
The Sapele that I used did not come from my usual source and after bringing the flywheel pattern inside a night of central heating caused it to warp. It went back flat after a few days in the workshop but I did not want to risk it moving in a hot foundry so decided to get patterns 3D printed in ABS, the base was OK.
After a few hours sanding the printed pattern was good enough for several layers of High Build primer and then gloss. The base was a lot easier to get prepped & painted. Patterns ready to be sent off for casting.
crueby:
That will be a nice one! :popcorn:
Sanjay F:
This is going to be an interesting one, so much progress already on a great looking unusual engine. I see the original advertising states it can be reversed how is that achieved?
It's going to be a fair size at 1/3 scale ............ following along :popcorn: :ThumbsUp:
Jasonb:
I'm hoping it will turn out to be a nice one too. Being quite an early engine it still has some of the look of a steam engine with its cylinder stood on the four columns which also means you can see all of what is going on rather then the more enclosed later engines.
They may have had a way to quickly change the position of the face cam on the top of the vertical cam shaft, much like you can change the direction of a steam engine with a slip eccentric.
It will end up about 350mm or 14" from the bottom of the flywheel to the top of the rocker arm. Alibre tells me it will weigh in the region of 8kg or 18lbs so still comfortable to move about.
Chipswitheverything:
Brilliant work on the CNC production of the patterns. The base is quite an intricate shape. Pity about the movement of the wood after spending the time and effort on what should have been a very useable large flywheel pattern. As others have remarked, this is quite a hefty model engine ...
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