Question for the old timers: FSI Tube sizes

I picked up an old FSI Orbit Model rocket kit in the bargain bin the other day, and unfortunately all of the body tubes are crushed :sad:

It does have a really nice transition that appears to be basswood, since it is much denser than balsa, and with that I have come up with the following dimensions:

Uppertube/Motor Mount: OD 0.925, I.D. 0.884, Thickness: 0.020
Lower Tube: O.D. 1.175, I.D. 1.125, Thickness: 0.025

Now these measurements can be off a bit either way seeing that the parts are not perfectly round either.
none of these are close to any Estes tubes that I have.
The upper tube seems close to a Centuri ST-8F, and the Lower to a Centuri ST-11

So has anyone been able to substitute the FSI tubes with something else? Did FSI get their Tubes from another manufacture?

Oh, since I know that you are all interested, some pictures of the kit:

orbit is ID 0.903 , OD 0.921 upper tube, ID 1.13, OD 1.17 lower tube. I used Centuri ST-8 as a decent substitute for rockets using the 21mm motors. FSI catalogs are on Ninfinger.org.

FSI's original motors were 21 and 27 mm in diameter.

I have a nice straight piece of the .925" OD FISI stuff, 6" long. I will mail it to you free of charge if you will give 2 bucks to the next poor soul you see with a cardboard sign.

Heck I'll even throw in a nosecone that fits the stuff.

Maybe the motor mount will make the lower AF "good enough"?

PM me your USPS address and I'll send it.

Blatz,
Thanks for the kind and very generous offer, but the tube lengths on this rocket are 9" long, so the 6" will be a little short for the kit. Thanks again, but I will pass, hopefully another poor soul will need those parts.

Goose

J Blatz said:

I have a nice straight piece of the .925" OD FSI stuff, 6" long. I will mail it to you free of charge if you will give 2 bucks to the next poor soul you see with a cardboard sign.

Heck I'll even throw in a nosecone that fits the stuff.

Maybe the motor mount will make the lower AF "good enough"?

PM me your USPS address and I'll send it.

Click to expand...

Thanks Roy. I had looked at those catalogs for the model itself, but I didn't look at the parts section.
The 1970 catalog has a nice list of the parts and sizes. It looks like I can get what I need from Semroc, and make an adaptor for 18mm engines.

RoyAtl said:

orbit is ID 0.903 , OD 0.921 upper tube, ID 1.13, OD 1.17 lower tube. I used Centuri ST-8 as a decent substitute for rockets using the 21mm motors. FSI catalogs are on Ninfinger.org.

FSI's original motors were 21 and 27 mm in diameter.

Click to expand...

Semroc carries the proper sized tubes. St 8F and st 11 i believe