Rotary-Vee Engine

[Rdean33422]

I saw this video the other day so I am off down another rabbit hole..




I started with the cylinders in the milling machine. The three piston holes and the center axis hole must all be in alignment to each other. At this point the outside of the cylinder has not been turned true and I was not too concerned if it was even straight up in the vise. After the holes were drilled the cylinder was taken over to the lathe with an arbor in the center hole and the outside was turned to final size.
This gave me the best chance to get everything aligned properly.


The video above and an article from Popular Mechanics magazine the December 1965 issue shows the pistons made in one piece and bent in the middle. I can only imagine the problems associated with that bend. All the pistons must be bent at the exact same angle and exactly at a 90 degrees. I don't want to try to do that if there is some other way. The Cardan joint should take care of that problem and you can see in the picture that is what I made. It swivels in the middle and will allow for the cylinders to be mounted at different angles to each other.


Test fit.


Progress so far
Thanks for looking.
Ray

 

[wce4]

Your build of this interesting engine is something I will be following closely. Is the flywheel to be machined and installed as per the drawings or as depicted in the video? Thank you for sharing. I just downloaded the drawings and instructions for building, found it on scribd.

 

[Rdean33422]

wce4 as you probably know I seldom follow any plans or drawings but there will be a flywheel maybe even two.


Before I jump right in to making the side supports I want to see what kind of tolerances are needed for a smooth rotation.
I cut this piece of steel in half and drilled some holes for the axles.


With the plates clamped down to my work bench I was able to turn the cylinders but with some difficulty.


I found out just what I had suspected. The axles must be in exactly the same plane as far as nod or rise is concerned. My angle iron supports are not 90 degrees either so first I need a better base and then a better alignment..
The angle of skew or turning one cylinder from being in line with the other cylinder to 90 degrees to it has little effect. The Cardan joint has taken care of that issue.

Thanks for looking
Ray

 

[Peter Twissell]

I've seen a few of this style of engine, but never built one.
It's often referred to as an elbow engine.

 

[Rdean33422]

Yes Pete it is but this one will be at an angle not 90 degrees. Thanks

I mounted the brackets on a poplar board at a 60 degree angle and spent the rest of the day getting the cylinders to turn smoothly.


This doesn't seem like it should be a big deal but the brass pistons are a close fit in the cylinders and they are binding. I have another reamer that is 0.001 over 3/8" so I will try that next.

Thanks for looking
Ray

 

[Peter Twissell]

Perhaps the binding could be relieved by allowing one of the cylinders to float radially.
I am thinking of it's bearing in an oversized bore, constrained by retaining plates front and back. This would be preferable to adding leakage.
I would suspect that oversize bores in the cylinders could create another source of binding.