Long coupler

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BDB

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I'm looking for a 16" coupler for a LOC 4" tube. I can't find anything longer than 8", besides the full-length couplers from ARR. Is that my only choice for something like this?
 

MikeyDSlagle

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Are you gonna use it as a coupler or something else.
Maybe get two pieces and join them with a loc stiffener inside or a piece of bodytube outside?
 

Wayco

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Balsa Machining has 3" coupler listed, they might have something bigger.
 

BDB

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Are you gonna use it as a coupler or something else.
Maybe get two pieces and join them with a loc stiffener inside or a piece of bodytube outside?
The plan is to make an AV bay that can be opened without unwiring everything. Here is my back-of-the-napkin design. The stiffener is a good idea, if nothing else is possible.

IMG_2252.jpg

Balsa Machining has 3" coupler listed, they might have something bigger.
Thanks. I forgot to look at BMS.
 

T-Rex

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Can't say for sure, but more than likely if you call LOC or Madcow, one of them will be able to sell you a 34" length, or possibly a custom cut piece.
Performance Hobbies has a 34" on their LOC list but it shows out of stock......
Wildman has it on his PML list in 34" pieces, but I am not sure if it would mate with regular cardboard tube....
YMMV
 

GregGleason

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Contact LOC directly to see if they can fill a special order from their stock. At worst you are no less for the wear. At best you have exactly what you need.

Greg
 

Nytrunner

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Brainblast (or brainfart depending on outcome): Since your internal bay splits open, What about using normal airframe tubing? You'll have to cut it anyway, and it may be easier to get than specific "coupler tubing"
 

Cl(VII)

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Some tubing will not want to be exactly round anymore once cut. Blue tube is this way, and may make it hard to get a good seal around your bulkheads. That flex could allow a bulkhead to pull down into the sandwich if force is applied in that direction. Perhaps a hatch style opening in your electronics bay could alleviate some of this, i.e. instead of sliced completely in half have a door in the bay. This would still be compatible with your removable coupler also.
 

BDB

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I have been thinking about this too. I suspect that I'll need to cut two couplers. Otherwise the saw kerf will prevent the coupler from being round. But I hadn't really thought about the structural issues that this could cause. If I'm going to do this, I definitely need to design something to compensate for the lost strength.
 

les

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After slitting lengthwise, I would look into using another coupler. Cut some strips lengthwise and bond on the inside. This will provide a lip for mating the 2 halves and improve the strength at the joint.

clamshella.jpg
 

Cl(VII)

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I have been thinking about this too. I suspect that I'll need to cut two couplers. Otherwise the saw kerf will prevent the coupler from being round. But I hadn't really thought about the structural issues that this could cause. If I'm going to do this, I definitely need to design something to compensate for the lost strength.
Maybe a couple of thin wooden (or 3D printed) half moon rings inside the coupler to help it keep shape? In a 4" tube you should have plenty of spare diameter for reinforcement.
 
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