Fill center of carbon bar with epoxy

[downunder]

Hmmm,


Looks like no one mentioned a big issue here:

- carbon tubes have a release agent ( medium) inside.

Meaning, pour epoxy in, and after cured can be easily popped out.

Learned this hard way...

[airsail]

Release agent (pva) is water soluble so you just need to wash it out. Solvents won’t remove it, only water.
I have mixed chopped carbon strands with epoxy and filled the centre section with this mixture. Then drilled and faired the hole for the depower line.
I did think about doing the eye thing, but decided that the chance of damaging the board with the eye was too great.

[Breze]

Airsail, how did you close one side of the tube near the center hole to prevent losing the epoxy? Problem is ( i have the same china cycle tube) the thicker diameter in the middle. Did you fill it with PU foam? I did not want to go this foam way and tried several plug methods. All failed. E.g. i placed a condom and blew it up by a PU tube etc.
I tried to get rid of the solvent withe aceton will try it with hot water.
Epoxy mixed with graphite gives a perfekt slippery surface
May i say this? I love your hole

[airsail]

Breze, I only drilled through one side, left the other intact. I cut 2 pieces of foam, the soft closed cell stuff they use in life jackets, and pushed it in to seal each side prior to filling with epoxy/carbon mix.
Yes, I like my hole too!

[Breze]

I will try this kiss method, thanks

[fluidity]

Mix graphite powder with your epoxy resin, If the dynema cuts into it, it will self lubricate. If you are thickening it stay away from anything with glass fibre or collodial silica or microbaloons. Cotton should be OK.

[downunder]

I do not think graphite is a way to go.

Simple reason: as slippery on the exposed surface, the same is inside the tube.

Simple test: pour it in a tube, and after cured, try to hit it with something. Did it move?

Second test pour inside longer tube, bend the tube. Did u hear cracking?

Third, leave tube on the sun. It will get hot, and expand making it to unbond.

Or, u have been lucky and all good.

PS
Filling the tube is easy with expanding PU foam used for windows,doors etc

Plus, no one can tell if PVA is used with wax. So, cleaning PVA only is not safe in my books. I always use wax in my molds.

[fluidity]

I do not think graphite is a way to go.

Simple reason: as slippery on the exposed surface, the same is inside the tube.

Simple test: pour it in a tube, and after cured, try to hit it with something. Did it move?

Second test pour inside longer tube, bend the tube. Did u hear cracking?

Third, leave tube on the sun. It will get hot, and expand making it to unbond.

Or, u have been lucky and all good.

PS
Filling the tube is easy with expanding PU foam used for windows,doors etc

Plus, no one can tell if PVA is used with wax. So, cleaning PVA only is not safe in my books. I always use wax in my molds.

The epoxy resin will still set hard. You have to blend the graphite fully in. It only lubricates when you cut into the resin and rub off graphite particles.
If the inside of the tube has PVA or other non stick coating then naturally it won't stay in place.

[fluidity]

I do not think graphite is a way to go.

Simple reason: as slippery on the exposed surface, the same is inside the tube.

Simple test: pour it in a tube, and after cured, try to hit it with something. Did it move?

Second test pour inside longer tube, bend the tube. Did u hear cracking?

Third, leave tube on the sun. It will get hot, and expand making it to unbond.

Or, u have been lucky and all good.

PS
Filling the tube is easy with expanding PU foam used for windows,doors etc

Plus, no one can tell if PVA is used with wax. So, cleaning PVA only is not safe in my books. I always use wax in my molds.

The epoxy resin will still set hard. You have to blend the graphite fully in. It only lubricates when you cut into the resin and rub off graphite particles.
If the inside of the tube has PVA or other non stick coating then naturally it won't stay in place.