Carbon Fiber Tail Booms?

BayDesigns

Active member
I'm looking at the possibilities of carbon fiber tubes, but I can't find ones that have a diameter of 0.5 in or above. Does anyone know where to get that? Also, how do you cut it without all those little carbon-dust daggers getting in your skin and lungs?
 

JasonK

Participation Award Recipient
how big of a plane are you making?

I have one that is 8mm diameter one that is 1m long and is fine for that length.

If you really need something big, using 3-4 rods with a ring support with smaller rods would likely give you all the strength you need and be lighter then a huge rod.

For cutting, you can tape the cut point, use wetting, cut somewhere with extraction/good airflow, respirator.
 

BayDesigns

Active member
how big of a plane are you making?

I have one that is 8mm diameter one that is 1m long and is fine for that length.

If you really need something big, using 3-4 rods with a ring support with smaller rods would likely give you all the strength you need and be lighter then a huge rod.

For cutting, you can tape the cut point, use wetting, cut somewhere with extraction/good airflow, respirator.
Nothing huge, probably a 3 or 4 foot wingspan. Just something that's a stable FPV platform for multiple cameras and a small payload. It's just a concept but I'm looking at ways to develop a low-cost SAR platform. Thanks for the cutting tips!
 

quorneng

Master member
Most carbon fibre tube is actually extruded (poltruded) from a resin impregnated with carbon filaments. The result is stiff but not as strong as if the fibres were continuous. The relatively thick wall makes it relatively heavy. I have found a glass fibre rod which is made from laid up glass fibre is virtually as stiff with a much thinner wall so is less than half the weight. In addition it is made over a mandrel so is tapered. It is also quite a bit cheaper.
This 52" pusher with a 350W motor uses a 28" glass fibre 'fishing pole' tail boom.
19May18.JPG

It actually uses the inner two sections of a 6ft 4 section pole that I bought very cheap from ebay.
 

BayDesigns

Active member
Would PVC pipe be usable? I have easier access to it, and it’s safer to cut. Cheaper, too. Obviously it’s heavier, but despite all the safety options available, dealing with all the dust and other not-so-nice stuff in CF tubing seems pretty risky when there’s a cheaper option available.
 

JasonK

Participation Award Recipient
Would PVC pipe be usable? I have easier access to it, and it’s safer to cut. Cheaper, too. Obviously it’s heavier, but despite all the safety options available, dealing with all the dust and other not-so-nice stuff in CF tubing seems pretty risky when there’s a cheaper option available.

Define 'usable' - It is really heavy for its strength, your likely to to do better with a wood spar.
 

BayDesigns

Active member
Usable would be fairly lightweight, and strong enough to survive a crash. Since I’m designing for easy maintenance, I can swap out different parts, so I can experiment with different materials. Thanks for the help!
 

JasonK

Participation Award Recipient
you also want something that isn't going to flex all over the place, else the flex will make your plane fly all wonky.