Offset centering rings?

[EchoVictor]

All,

Does anyone know of a vendor that makes offset centering rings? By offset, I mean that in a cross-sectional view, the "12 o-clock" position of both tube circles would be touching, as opposed to the concentric circle view of a standard centering ring.

I'm looking for a BT-20 to BT-50, and a BT-50 to BT-55

Thanks,
EV

[CPMcGraw]

All,

Does anyone know of a vendor that makes offset centering rings? By offset, I mean that in a cross-sectional view, the "12 o-clock" position of both tube circles would be touching, as opposed to the concentric circle view of a standard centering ring.

I'm looking for a BT-20 to BT-50, and a BT-50 to BT-55

Thanks,
EV

As in, for example, rings for the off-center motor tube used in the Centuri Space Shuttle?

BMS for certain, with his custom-cut ring service; SEMROC possibly (Carl's Krellvenator in action), you'd need to ask him.

[Doug Sams]

Does anyone know of a vendor that makes offset centering rings? <snip> I'm looking for a BT-20 to BT-50, and a BT-50 to BT-55EV, I'm with Craig. I'd go with BMS. IIRC, Bill made these rings for me using a DXF file: http://home.flash.net/~samily/stuff/ProCluster6.pdf

Since your holes are off center, his usual setup (shape 15 in the BMS catalog) is not suitable, and a DXF is called for. Here are some DXF files that should work (zipped, attached). Ping him with them and see what he says.

BTW, I added a mark for alignment. You'll need it to keep the tubes from getting cock-eyed.

I've thought about using rings like this for doing a cluster where I want the outboard motors to be as close to the centerline as possible. The Estes X-prize kit with the 6 outboard tubes (Rubicon?) is a great candidate for clustering, but I don't need 24mm motors in the outboards; 18mm motors (or smaller) will work fine. Having this kind of ring would help that project (if I ever get 'round tuit :)

BR,
Doug