LT-275 tube coupler

[EXPjawa]

I am looking at a project that will need a segment of the old Semroc LT-275 tube, which itself I believe stems from Centuri heavier-duty tube. eRockets.biz sells the tube in 8, 22, & 30" segments. Of course, the design needs 36", so I'll need to splice a couple segments together. Not a big deal, but the only coupler I can find is a solid balsa piece. That won't work, because the spliced joint is about 6" above the motor tube and 20" below the body separation.

What all that means is that I'd like to find a typical tubular tube coupler for LT-275. If I have to resort to making one by sectioning an extra piece of 275, I will, but I'd rather buy one that fits properly off the bat. Does anyone have any leads on a source? eRockets doesn't show one, BMS doesn't dabble in Centuri sizes.

Thanks

 

[kuririn]

I am looking at a project that will need a segment of the old Semroc LT-275 tube, which itself I believe stems from Centuri heavier-duty tube. eRockets.biz sells the tube in 8, 22, & 30" segments. Of course, the design needs 36", so I'll need to splice a couple segments together. Not a big deal, but the only coupler I can find is a solid balsa piece. That won't work, because the spliced joint is about 6" above the motor tube and 20" below the body separation.

What all that means is that I'd like to find a typical tubular tube coupler for LT-275. If I have to resort to making one by sectioning an extra piece of 275, I will, but I'd rather buy one that fits properly off the bat. Does anyone have any leads on a source? eRockets doesn't show one, BMS doesn't dabble in Centuri sizes.

Thanks

Looking at the dimensions of the series 27 tube, I think that might work as a coupler:
ST27 OD = 2.70"
LT-275 ID = 2.75"

Here is the erockets page:https://www.erockets.biz/st-27/

I haven't tried it, so do so at your own risk. Good luck.

 

[EXPjawa]

Thanks for the tip, that may be a solution.

 

[MoeB]

Thanks for the tip, that may be a solution.

And of course you can always use a piece of the tube in question...slice it lengthwise twice to remove the necessary amount so the new circumference fits inside the tube. I have used this method for years for all sorts of odd-diameter tube all the way up to 12" and larger concrete form tubes for making couplers, nose cone shoulders, etc. Do whatever works for you but you can always make your own in a pinch if you have the right material.