Nose cone to body tube sizes

[Jacktango22]

This may be a dumb question but here goes. Back in hobby with retirement and really having fun designing on Open Rocket and then building and flying. To date I have simply followed the Estes BT system when buying and fitting out nose cone and body tube for my designs.

But I have noticed but not focused on the vendors who have, for example, a 2.56 inch body tube. I guess my question is whether these sizes correlate to a BT size … or is there a whole other system I need to explore that matches up body tube and nose cone sizes for design purpose.

Thanks

 

[COSTransplant]

https://www.erockets.biz/body-tube-sizes/
Pretty sure this is what someone sent me when I asked the question a little while back.
Hope it helps!

 

[SolarYellow]

In addition to what's in the erockets list, you can add Quest, other AeroTech sizes, LOC Precision, and probably some BMS.

 

[BEC]

Apogee also has some good reference info. They tend deal directly in diameters in millimeters where they can, but have some cross-reference data as well.

 

[Jacktango22]

Thanks guys for the help.

 

[bjphoenix]

There is some overlap in thin wall tube sizes that are used for low power and thicker walled tubes that are used for mid power and high power and mixing those parts will cause problems. For instance there is an Estes tube that is about 2.6" outer diameter and a LOC tube that is about 2.6" outer diameter. I don't think you could interchange nose cones very well. Also there are mid power and high power parts made in phenolic and in fiberglass. Years ago I bought a phenolic tube and I've started building a rocket using that tube with a LOC nose cone. The nose cone is just a tiny bit smaller than the tube, it will work but I'll have to tape the shoulder a little bit.

If you are buying current production parts all from the same vendor you should be able to match things pretty well, if you have some old parts to go with some new parts you could have problems. I had a batch of old nose cones in my stash and I don't remember which it was offhand but I had a couple that looked like they should fit BT-50 tubes (or was it BT-55?) but they were just a bit too tight.

 

[SolarYellow]

When I bring new tubing into the rocket room's inventory, I write what it is inside one end. When building, I always make sure to cut lengths off the other end. I have an Excel spreadsheet with body tube sizes from various manufacturers in inches and mms. Need to add all the Semroc, Apogee, Quest and AT stuff one of these days.

 

[tsmith1315]

But I have noticed but not focused on the vendors who have, for example, a 2.56 inch body tube. I guess my question is whether these sizes correlate to a BT size … or is there a whole other system I need to explore that matches up body tube and nose cone sizes for design purpose.

Definitely a legitimate question. The best straight answer is no.

Here's another good resource which shows OD x ID x wall thickness x length. It's also a good resource to correlate the Estes BT tube designations with Centuri's ST designations along with actual measurements. Look under the Kits & Bldg Supplies > Low Pwr Body Tubes and couplers and the Cones & Transitions tabs :

https://www.balsamachining.com/#

You have to watch wall thickness to be sure nose cone shoulders are correct for your use. In general, that's where high power tube differs from low power tube and can keep nose cones from interchanging precisely.

 

[Jacktango22]

Thanks again for the input. This is all helpful information.

 

[jqavins]

There is some overlap in thin wall tube sizes that are used for low power and thicker walled tubes that are used for mid power and high power and mixing those parts will cause problems. For instance there is an Estes tube that is about 2.6" outer diameter and a LOC tube that is about 2.6" outer diameter. I don't think you could interchange nose cones very well. Also there are mid power and high power parts made in phenolic and in fiberglass. Years ago I bought a phenolic tube and I've started building a rocket using that tube with a LOC nose cone. The nose cone is just a tiny bit smaller than the tube, it will work but I'll have to tape the shoulder a little bit.

And then sometimes it's the IDs that match, so a nose cone shoulder fist fine but there's a diameter step on the outside. I ran into that very recently.

Most vendors are very good about answering questions. If none of the advice here works (it probably will) then just ask the vendors for both ID and OD of tube, both nase diameter and shoulder diameter of cones, and see what matches.

When I bring new tubing into the rocket room's inventory, I write what it is inside one end. When building, I always make sure to cut lengths off the other end. I have an Excel spreadsheet with body tube sizes from various manufacturers in inches and mms. Need to add all the Semroc, Apogee, Quest and AT stuff one of these days.

And you need to post it so the rest kf us may benefit from your diligence.