Source for 4" coupler for MDRM tubing?

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ThirstyBarbarian

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I need to repair some damage to my Mighty Pod Rocket, which is based on a Mega Der Red Max kit. What I need is a section of coupler that will fit the Estes 4" tube (or 3.9" if that's what it is). Often when I've ordered parts, I've ended up with something I though would match what I have, but it doesn't. Does anyone know of a source of coupler that is known to fit this tube?

Thanks!
 

rharshberger

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iirc the MDRM uses standard HPR type airframe and couplers. Hopefully some is able to confirm that for you.
 

ThirstyBarbarian

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Are all Estes models based off the BT sizing? Maybe try a BT-101 coupler. Unlce Mike has them.

https://www.unclemikesrocketshack.com/Parts/Body_Tubes/Body_Tubes.html

So does eRockets.

https://www.erockets.biz/bt-101-2/

I haven't tried them.
Thanks. I think the PSII rockets all use a different kind of tubing than the BT tubing. I think the MDRM is based on something other than BT-101. If someone could confirm that this BT-101 coupler will work, then these look like good sources for purchasing it, but I think I need something else.
 

ThirstyBarbarian

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iirc the MDRM uses standard HPR type airframe and couplers. Hopefully some is able to confirm that for you.
It is heavier than LPR tubing, but I'm not sure if it is the same as used by LOC or Aerotech. My feeling is that it might be lighter and maybe the diameters are not exactly the same. it would be great if a piece of LOC coupler would work.
 

75Grandville

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o1d_dude

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You could always slice a larger coupler lengthwise and overlap the cut ends to make it fit your needs. The joint won't show from the outside.

Epoxy the overlap so the laundry doesn't snag on anything.

edit: Bill beat me to it.
 
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75Grandville

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You could always slice a larger coupler lengthwise and overlap the cut ends to make it fit your needs. The joint won't show from the outside.

Epoxy the overlap so the laundry doesn't snag on anything.

edit: Bill beat me to it.
Great minds...

Us too...
 

Nytrunner

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Thirsty,

When I've gone shopping for PSII repair parts, the only source was Estes. Their PSII sizes are unique, AFAIK. Unfortunately, it looks like they've sold out of that particular coupler.

What you can do is take a section of 4" tubing, cut out ~1/8" vertically, and make your own custom-sized coupler. You can still get a 4" BT to work with: https://www.estesrockets.com/rockets/pro-series/parts/085868-pro-series-iitm-4-od-slotted-body-tube. Best of luck on this!
You could always slice a larger coupler lengthwise and overlap the cut ends to make it fit your needs. The joint won't show from the outside.

Epoxy the overlap so the laundry doesn't snag on anything.

edit: Bill beat me to it.
Great minds...

Us too...
+4 on this method for Pro Series II stuff.

I used a 3" mailer tube with a slot cut to reinforce a tube wrinkle in my new Leviathan. (Wasn't damaged in flight/landing. A full bottle of antifreeze fell on it......)
Honestly, the mailer tube is probably thicker and stronger than a PSII coupler anyway lol.
 

dhbarr

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My MDRM NC fits perfectly in my Polecat 98mm MMT, FWIW.
 

ThirstyBarbarian

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Thanks for the ideas, everyone. I will probably just buy an LOC coupler and cut it as suggested. I've got a few other things to order from them, so that is probably the best solution.
 

ThirstyBarbarian

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Thirsty,

When I've gone shopping for PSII repair parts, the only source was Estes. Their PSII sizes are unique, AFAIK. Unfortunately, it looks like they've sold out of that particular coupler.

What you can do is take a section of 4" tubing, cut out ~1/8" vertically, and make your own custom-sized coupler. You can still get a 4" BT to work with: https://www.estesrockets.com/rockets/pro-series/parts/085868-pro-series-iitm-4-od-slotted-body-tube. Best of luck on this!
Ideally I would get exactly the right part from Estes, but I don't think they ever carry the 4" coupler. That coupler is not used in any of their kits, so I don't think they ever stock it.
 

kitbasher99

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I'm too am working on a rocket based off the Mega Der Red Max. I got a coupler from Randy at e-Rockets. It was a Semroc CPL-101. It and the Loc 4" coupler fit the same, but the Semroc one wasn't as expensive.

It's nice having e-Rockets as my local supplier. I can walk in and check inventory whenever I need to.
 

K'Tesh

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I'm too am working on a rocket based off the Mega Der Red Max. I got a coupler from Randy at e-Rockets. It was a Semroc CPL-101. It and the Loc 4" coupler fit the same, but the Semroc one wasn't as expensive.

It's nice having e-Rockets as my local supplier. I can walk in and check inventory whenever I need to.
Maybe when I come back to the US, I should move to Ohio so I can save myself a ton in shipping.
 

dhbarr

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Maybe when I come back to the US, I should move to Ohio so I can save myself a ton in shipping.
... and also go broke from being so unbearably close :-D
 

ThirstyBarbarian

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I'm too am working on a rocket based off the Mega Der Red Max. I got a coupler from Randy at e-Rockets. It was a Semroc CPL-101. It and the Loc 4" coupler fit the same, but the Semroc one wasn't as expensive.

It's nice having e-Rockets as my local supplier. I can walk in and check inventory whenever I need to.
Thanks for the info! I was hoping to find an exact fit.
 
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