DIY Carbon fiber barrel?

[ntsqd]

Thanks!

 

[Mram10us]

Decided to take the 28 nosler barrel out there and turn it closer to min tolerances. It started out as a fluted brux #5 with brake, lug and receiver at 79.9oz. With the finished contour it is down to 60.4oz. We'll see what it is finished, but that is a great start. Also, left plenty on the chamber

 

[tobnpr]

I've worked with glass/composites/epoxy restoring a couple of my past "holes in the water" but zip experience with cf.
What type of resin is used? I assume it's a vacuum-bagged process?

 

[Orange Dust]

If I was going to try it, I would lay up unidirectional carbon lengthwise and vacuum bag it. Then turn it to contour and strech a carbon woven tube over it and bag that for looks. Remember epoxy adds no strength so you want just enough to bond the fibers.

 

[Mram10us]

If I was going to try it, I would lay up unidirectional carbon lengthwise and vacuum bag it. Then turn it to contour and strech a carbon woven tube over it and bag that for looks. Remember epoxy adds no strength so you want just enough to bond the fibers.

Vacuum bag for a tube? It wont need any pressure if it is already a tube. Regarding the vacuum bag process for a barrel, it seems most are wrapping the material with shrink tape then cooking.

 

[Clay Target Guy]

the vacuum compresses the carbon fibers to the barrel and helps remove air pockets.

 

[Mram10us]

the vacuum compresses the carbon fibers to the barrel and helps remove air pockets.

If the cf is already a tube, it wont compress. Sleeves, yes. Im guessing you mean sleeves and not tubes

 

[Mram10us]

Here is a video showing an option im going to try. Make the exact size i want, then turn it down

 

[Clay Target Guy]

are you using pre cured tubes of a certain size or are you laying up raw (uncured) material?
I guess I am confused

 

[Mram10us]

are you using pre cured tubes of a certain size or are you laying up raw (uncured) material?
I guess I am confused

Both. From what i understand, a tube is premade and sleeves are fabric you have to epoxy and compress somehow. Just making sure we were on the same page with definitions.

 

[Clay Target Guy]

Compressing the fabric is where the vacuum comes in

 

[Orange Dust]

Vacuum bag for a tube? It wont need any pressure if it is already a tube. Regarding the vacuum bag process for a barrel, it seems most are wrapping the material with shrink tape then cooking.

No. to be technical I am talking about a braided sleeve. Put it on like a sock, add epoxy and vacuum it. The reason barrels aren't made this way is it would be too labor intensive to manfacture and sell. It would be stiffer. This stuff is much harder to work with compared to fiberglass, especially in filament form.

 

[tobnpr]

So, watched the video.
Will "not" using a release agent in the roll-wrap method shown, absolutely prevent de-bonding of the barrel from the wrap?

Cure temperature of the embedded epoxy is only 250 degrees. No idea what the temperature of the barrel will be ahead of the full diameter steel chamber- but given it's turned down to 5/8" (if I understood you correctly) it's going to be waaay hotter than that after a few rounds down the tube. My concerns would be different coefficients of expansion (as he mentioned in the video), high temperatures, and possibility of de-bonding. How well does the material conduct heat away from the barrel? Barrel vibration, harmonics, uneven temperatures... sounds like a challenging environment.

Never seen material pre-impregnated with a heat-cure resin. I've only used liquid resins- which as mentioned are vacuum bagged not only to remove air, but excess resin as too much will weaken the part.

Good luck with it, we're all going to be standing by for the results of the "experiment".

 

[Mram10us]

Compressing the fabric is where the vacuum comes in

Shrink tape is used on tubes according to the cf companies ive talked to. Ill go that route. Much easier than vacuum bags