Thorp Air Command - T18.net

Have there been any engine mounts used on the T18 for conical mount Lycs which did not use the aluminum ring? Could a conical mount be fabricated in a similar fashion as the dynafocal mount is fabricated? Are there any pictures or drawings of an animal like that? Is there an engineering reason behind the need for the aluminum ring other than mating up to the flat mounts of the 0290G?

Dave

Dave,

You're not alone in that question. I've seen plans for both the conical mount with giant aluminum horse shoe ring and the dynafocal mount, but none for the conical w/o aluminum ring. I don't know if any others did, but I actually started a mount for my O-320-B3B as you say. This engine has the flat back and conical seats for attachments like the GPU's. But half-way I decided to use the aluminum ring and go with the plans. In some cases I'm not feeling so 'experimental'. I admire the guys that do (and are successful).

Les Krumel
Albuquerque

A GPU engine does not have the mount holes that would use the conical rubber bushings . The holes are straight drilled holes. THis would require the horseshoe ring adapter. I made a conical mount for a 0-320A2 which has the mags that you can rotate and worked.
The engine that is was to go on was a 0-320 with mags you could not rotate and the mount would not fit. I just never got back to modifying it.
I still have the fixture used to make the mount.

Glad for the update on the GPU, Bill.

I guess the thing to note is the flat back. And since you mentioned it, I now remember making aluminum conical inserts to replicate the straight holes in the GPU case (age starting to show). Then I used the large 'Lord' rubber mounts between the O-320 case and horse shoe ring. I made the ring all one piece for my installation. Plans allow an offset splice to allow rotation of the right mag. But in my case I used an impulse coupling on each mag to get the spacing and allow adjustment without the offset splice. My album has some photos. Nevertheless, no one else has said anything yet of a conical mount without the aluminum ring...

Les

Bill, did you make your conical mount (without the aluminum ring) in the same general arrangement as the dynafocal mount was made? Any chance you would have a picture of the mount you made that you could email or post?

Dave

I took a dynafocal mount engine and mount and made a fixture, removed the engine and bolted in the conical mount engine and made the fixture to adapt the conical mount which gave me the same angles and distances as the dynafocal

Just to make sure you know, I have conical mounts and rings available.
Cubes

Bill, thanks for the input. I have sent you a couple PM's, let me know if you are getting them if you get a chance.

Cubes, I am sure I will be ordering some parts from you as this project moves forward. Currently still trying to understand what all I have, what can I repair and then what do I need to procure some way. Thanks again for your reminder.

Dave

Not a problem. Here to help. I don't think there is anything special about the ring. I've talked about making one out of 4130 instead of 2024 which is expensive.
Cubes