Estes/Semroc body tube compatibility

[brrrett2]

Does anybody know if semroc body tubes, couplers, nosecones, etc., are compatible with Estes parts? For instance, in open rocket, it lists the O.D. of the Semroc BT-60 coupler as 1.63" and Estes at 1.6".

 

[BEC]

Semroc BT-sized parts should be exact matches for Estes ones of the same type. The current product page on eRockets.biz doesn't give any dimensions other than that a JT-60C is 1.5 inches long.

I can't speak to whatever version of the internal parts library in OpenRocket you have or how accurate that info might be.

 

[kuririn]

Semroc body tubes are from the old Centuri "ST" and "LT" designations. Some are compatible to Estes tubes, some are nearly compatible, and some are not.
For example, BT-5 and ST-5 are compatible. BT-20 and ST-7 are nearly compatible. ST-7 has the same ID but the tube is a little thicker IIRC. Same with BT-50 and ST-9.
Per Randy at erockets there is no difference between the BT-60 tube and the ST-16.
A Semroc BT-60 coupler should work with an Estes BT-60 tube. Even an ST-16 coupler should work.

 

[astronwolf]

BT-20 and ST-7 are nearly compatible. ST-7 has the same ID but the tube is a little thicker IIRC.

ST-7 is equivalent to the Centuri tube of the same designation. It has a slightly larger ID and OD than Estes BT-20. I replace BT-20 motor mounts in Estes kits with ST-7 because of the slightly looser fit for motors. They are not the same ID as BT-20. Same goes for BT-50 and ST-9 - they are different.

eRockets names their tubing the same as Estes and Centuri did, so an eRockets BT-5 is the same as Estes BT-5; an eRockets BT50 is the same as Estes BT-50, and so forth.

eRockets shows dimensional data for their tubes, so that ought to help determine what is compatible with what.

 

[brrrett2]

Thanks all,
Some really useful replies to my query.