BT-55 to 29mm centering rings

[user 38430]

I can’t find these, anyone know a source? I want to mount a 29mm engine tube in a B5-55 body tube. I can fabricate one, but would rather not.

 

[Zeta]

consider looking at the paper rings that Balsa Machine has you might find one that is the correct thickness but larger in diameter.... cut small section out and wrap your 29mm tubehttps://www.balsamachining.com/#

 

[SolarYellow]

Balsa Machining

CR52H55-F

1.283x1.215x.05thk fiber

$0.30

BUY

Looks like a material supply problem, but these guys offer custom service:
https://www.rocketryworks.com/1-8-inch-thick-custom-centering-rings-per-ring/

 

[lakeroadster]

I can’t find these, anyone know a source? I want to mount a 29mm engine tube in a B5-55 body tube. I can fabricate one, but would rather not.

That's a tricky size to make. I made my own for my Hammerhead, the annular thickness is only about 0.036" = (1.283-1.21)/2.

 

[user 38430]

Thanks everyone for the suggestions. I made one by wrapping the motor tube with a section of a Paper towel tube that fit perfectly. I figured I can't be the only one who wants to make a BT-55 rocket with a 29mm engine but I guess most just go to BT-60. I may just build a Min Diameter rocket again since 29 MM tubing is available.

 

[c0c0m0ke]

I've been building Rockets since Nov. 2014. And it wasn't until about a month ago when I learned that a BT55 is not the same as a 29mm tube, and I have been thinking all this time they were. I guess that shows how often I use either or. I can appreciate the pain of trying to find centering rings to fit the 29mm inside the BT55, it is a slender but necessary device.

 

[Sooner Boomer]

I cut strips of typing paper and wrap them around the body tube while lightly applying thinned glue. If I over-wrap, it's usually fairly easy to peel off before the glue sets up. Depending on how strong the "rings" need to be, I cut the strips from 1/4" to 1/2".

 

[dhbarr]

Thanks everyone for the suggestions. I made one by wrapping the motor tube with a section of a Paper towel tube that fit perfectly. I figured I can't be the only one who wants to make a BT-55 rocket with a 29mm engine but I guess most just go to BT-60. I may just build a Min Diameter rocket again since 29 MM tubing is available.

29mm nose cones are rarer than they should be.

 

[Back_at_it]

Pete,

What you're looking for is a BT55 coupler stock from BMS. The coupler slides inside the BT55 then the 29mm motor tube slides inside the coupler.

It's a perfect fit. I have some pieces I can give you. Lets talk this morning.

 

[user 38430]

29mm nose cones are rarer than they should be.

I bought a Quest Penetrator kit and used the upper half and nose cone (both 29mm) for my F Min Diameter build, flew great 2 times.

 

[Back_at_it]

I bought a Quest Penetrator kit and used the upper half and nose cone (both 29mm) for my F Min Diameter build, flew great 2 times.

And he got it back. Seriously this guy is the luckiest person I've met when it comes to recovery.

 

[SolarYellow]

Pete,

What you're looking for is a BT55 coupler stock from BMS. The coupler slides inside the BT55 then the 29mm motor tube slides inside the coupler.

It's a perfect fit. I have some pieces I can give you. Lets talk this morning.

That is such awesome information that I PDF'ed the post and saved it in my archives. Thanks!

(Would make a heck of a beefy tail can for a near-MD rocket.)