Carbon laminations

[Ronaldlee]

I am just starting to plan out building my first bow and I have read a lot of post and watched a few build-a-longs. I haven't seen anyone using carbon lamination's yet and was wondering if there was something of a problem with using this material on a home built bow. Any information would be appreciated.  Thanks, Ron

[jess stuart]

I am not the best person to ask.  I have only tried it once I just subbed carbon for glass.  It shot great but only lasted about fifty shots.  I have since learned that you really need to make some design allowances for carbon.  I will try again one of these days.

I would suggest that you build a proven design using glass for you first one.  I think your chances of getting a shooter are better.  I am not saying you can't be successful but the odds may be somewhat stacked against you.

[Gundog68]

I tried my first and second laminated bow with it. I made some basic mistakes also. So they shoot great. But only 20 times, then they delaminated at the carbon level. I made several bow´s with glass since then without problems. I looked also for the benefit i would gain with carbon and all expert´s are the same: Without special design for carbon, you would get a little bit more stable bow (torsion) and maybe a very few more fps.

Gundog

[AZ_Shooter]

Also, don't overlook the cost of carbon.  Carbon laminations are at least double what you pay for glass.

[Joey V.]

I am actually shocked to hear your Carbon limbs delamed at the carbon???  Carbon fiber laminations are basically (from what I understand) carbon fiber and epoxy type resin.  Nothing sticks to epoxy resin better than more epoxy resin.  I have heard of limbs having so much whip effect that inner veneers can be destroyed by the force and then cause all sorts of issues of veneer cracks.  
I started building by using Bingham’s bow designs and if you follow the letter of the law he writes and use his design you shouldn't have an issue.  Maybe the carbon was bad?  I would call your supplier and tell them what happened.  If it happened to everyone they might refund you.
P.S.  This is all my VERY humble opinion. I am by far just a slightly experienced beginner at best.

Good Luck.

[Ronaldlee]

Wonder if Carbon requires a special epoxy,heat or pressure treatment to get the bond strength ?

[Joey V.]

Hey guys,  You do not need a special epoxy or anything different than any other lamination.  You MUST cook the glue and let it completely cool down before taking it out of the press.  This goes for any lamination IMHO.  Guys say they can work on it right away still hot and that’s fine but I don't have the $$$ to waste if it doesn't work out one time let alone my customer reputation..
I called Bingham this Morn and asked about carbon lams.  He said in his experience you only want to put it on the target side of the limbs and also want to cover it with glass. He experimented with Carbon and no glass and it always ended bad. It is awesome that guys Like Elmont and others on this site share info freely. We get to stand on the shoulders of many yrs of experience!

[jess stuart]

There a bows being built using carbon as the skin, no glass over the carbon.  They may or may not be using the same glass that Binghams sells.  I do believe that using carbon requires that allowances for the carbon be made in the bows design.  Carbon is a very good material just not quite as forgiving as glass.

[Ronaldlee]

Thanks to all of you! This is the information I was looking for.  Ron

[PV]

Built 3 with Binghams carbon on the back only.NO glass over the carbon. All are good shooters. Most of the problems I've heard about with carbon comes with putting carbon on the belly in a bow that is not designed for it.

 Carbon is stiffer than glass. For instance on my 3 piece R/d bow the stack height for a 44# bow with glass results in a 66-68# bow replacing the back glass only with carbon.  

For your first bow I would suggest staying with glass until you get your formula down. As stated above carbon is pricier than glass.

[Ronaldlee]

Sounds like good advice. I ordered the plans and CD for a long bow today from Binghams. I'll stick with the plans on this first one. With luck, I'll end up with a shooter. Save the carbon till I know what I am doing.

[machomanandysavage]

We built up 3 bows using carbon. We used it under the glass and on the back of the bow only. Each of the bows has been shot over 1000 times and no issues have come up so far.

I don't know if the carbon adds performance or not. I spoke with Elmont at Bingham's, and he said it would add 5 fps, basically making a 50# bow shoot like a 55#

The carbon laminations they sell are sanded both sides and meant to be placed under glass. I was reading the Traditional Bowyer - More Unnecessary Fun" book - and he uses caron on the back with no glass over it - but talks a lot about it being a different type of lamination - maybe a different weave??

At any rate, after reading about some failures people had I haven't had the guts to try a bow w/ just carbon.

I like using the carbon for stability if nothing else - maybe you get a little performance gain, maybe not.

As a side note on the epoxy - I have have used smooth-on EA40 baked between 150-180 degress for 6 hours.