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I'm curious if anyone has any experience applying woven carbon fiber or carbon/kevlar as an alternative to traditional finishes. I have at least one custom who wants to try it out, and I have no objections since it will have a unique yet polished look while being sufficiently rigid that it should have no adverse impact on tone. Advice from actual experience would be appreciated, in case there are red flags I haven't thought of.

no experience. but wouldn't the effect of the adhesive+kevlar/carbon exhibit similar attributes as a top that is too thick...? or would you make the top thin to compensate?

Similarly, my inclination would be to laminate the CF onto a thinner top if that's the way the customer wanted to go. A long-setting water thin epoxy and a high vacuum would make a nice composite plate out of them, making sure to seal the other sides of the top so the epoxy doesn't impregnate it too much.

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

This will only be on solidbody guitars, so top thickness isn't a concern. I originally came up with the idea when a customer asked about having protective metal covers machined for the points on a king-v style body... While I could make them from metal, covering the whole thing in CF would provide the desired protection and at the same time gaining a unique aesthetic without sacrificing tone and I'll likely save enough time from the finishing process to hit a lower price point. Hopefully, I can also devise a way to "inlay" some CF decorative designs as well.

I can post images if necessary, but another question is how should I go about applying and cutting pieces to create clean lines between contrasting pieces? For example: on a king-v with chamfers around the top, how could I apply a red cloth and then cover the back, sides, and top chamfers with black?

Is there potential that sufficient strength will be added such that alternative body materials such as pine or spruce might be reasonable options?

Hugh, this might offer some insight.

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David Morris

...you can make a perfectly fine electric guitar body out of almost anything....certainly pine and spruce. as long as it is a reasonable thickness..."reasonable" meaning, as thick as the neck is, give or take

I have seen guitars with a carbon fiber look created by silkscreen and airbrush on more than one custom guitar.A much easier route to the look your customer wants. The metal plate thing seems to be very "in" right now with more and more doing it which means they will most likely not be worth too much when the trend dies.

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

How about just using the film wraps? Like this.. http://www.carbonfiberfilm.com/?gclid=C ... Mgod_34Agg

Thanks for the input. When I try this out I will definitely be using resin and real CF. The initial request is addressing a structural need, but as long as I'm exploring this possibility I might as well consider making use of the cosmetics. I have an acquaintance who as built several prototypes using CF reinforced bamboo... But I already know more about working with and processing the stuff than he does, although I still don't consider myself to be a top expert. I haven't spoken with Ned Steinberger for a few years, and I know he's been down this road as much as anyone in the industry. Other than that, it looks like it's time to hit the books and report my results when I have something to show off.

I've made quite a few long range benchrest rifle stocks with carbon fiber and its kind of a pain, looks good though. Getting it to lay totally flat usually take a large flat nonstick surface and some weight. It eats high speed steel, carbide does ok and its easy to sand. On the V, I would have the blank oversize, lay up the carbon fiber, then do your machining.

A nice bubble free clear coat is going to be the biggest challenge.

There are a number of processes that get you to that level of clarity I know you want...but the only one you can really do here is quite labor intensive.

Here's your real problem. A wet layup, no matter how well done is going to leave pinholes which will allow access to more trapped air below the cured laminate. With luck, a sprayable polyester sanding sealer will fill these holes, otherwise any topcoat is going to be very difficult to apply evenly. That's a risky bet.

The other option is to vacuum bag the layup to remove bubbles from the laminate....but you have to seal the wood thoroughly before the layup or the vacuum will simply draw air through the wood as it cures. So....seal the wood well, do a wet layup, vacuum bag with peel ply and blotter, cure, prep surface, spray clear polyester sanding sealer, cure, prep surface, spray clear polyester or urethane top coat, cure.....and viola!....pristine carbon fiber clarity. What a hassle...

Looking over the design requirement of wanting to provide some impact resistance to to corners and edges...carbon fiber isn't the best fiber choice. Kevlar or even S-glass will server better in that function. Also, having numerous flat pieces converge at a corner or edge without continuus fiber AROUND the corner or edge will provide zero reinforcement. It's more likely that equal impacts on a such a laminated surface and a painted wood surface would result in the laminated surface being more damaged and unsightly.

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I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic

I was hoping you might chime in. The two approaches I've been considering are wet layup under vacuum applied directly to the instrument, or fabricating molds and attaching the composite shortly after the initial cure. Since everything will be machined with CNC my hope would be that attaching the nice bubble-free sheets should border on painless.

There may be more to consider with respect to durability. In the case of the pictured design I have been working under the assumption that each face would have its own piece of fabric applied. The side/edgeband would be a single strip. It may well be more trouble than its worth... In which case I can always fall back on the simple explanation of: guitars get dings over time especially when used to record albums and survive multiple tours.

Hugh, I am curious as to what allowances will be made for expansion, contraction and general movement of the wood underneath?

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

None, aside from balanced construction. Resin is not overly different from a reactive finish, both can tolerate movement just fine. CF/wood sandwiches are relatively common in some circles such as model airplane construction. It's a cheap and lightweight way to shift the moment of intertia and make it really stiff.

Explain that further, Hugh...I'm not getting the picture.



In which case my previous admonition will apply. Having separate carbon fiber woven cloth panels cover each surface means they all their edges will meet at the point where dings usually occur....on the tips and edges. Actually, an edge impact on such a structure is going to be WORSE cosmetically than if there was no reinforcement at all because the properties of the laminate will work then to peel itself off locally from the impact zone. After an impact you'll have the smashed material in the impacted area but ALSO a much larger area around the impact zone where the laminate lifts off the wood. The ONLY way all this doesn't happen is when the fiber is continuous around that edge...and that's REALLY hard to accomplish in a wet-layup situation.

This would be an ideal application for a woven composite "preform"...fiber specially woven to the shape and fiberlay requirements of the design...haha...SO far beyond the guitar building world it's humorously impractical.

I'm interested in hearing more about your molding idea. Though I don't understand what you are thinking it may represent the only option to provide actual edge reinforcement. Otherwise the carbon fiber is merely cosmetic...which I don't judge...but it's a lot of work for that look if you really want to go all the way downtown with that look....the deep, clear, bubble free look.

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I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic

Understood. I have a few BBQ events to attend, and some explanatory drawings to prepare... But I will answer your questions so that you can weigh in with your expertise. The short version of improving impact resistance is due to a large seamless section around the edge. In the meantime I hope everyone has a pleasant Memorial Day.

Alder body strat covered with CF I made few years ago for a customer.

Agreed about the resin, the CF cloth on the other hand has a tensile strength of something like steel. Creating a sandwich still leaves the wood exposed on quite a few surfaces and allows for movement. This is different from completely encapsulating the wood in a rigid structure made of CF and resin. IME wood does not like compartmentalization and will usually show it's disagreement with these situations at some point in time.The wood will expand and move with changes in RH, you can not stop that.

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

It looks like one piece was laid over the top like a drop top Filippo.

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http://www.CostaGuitars.com
PMoMC

Yep, that's why the black lacquer creates a burst around the edge.

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

Yes, the CF fabric covers only top of the guitar. Back and sides are painted in black with the burst on top to hide the edges of fabric.

I'm curious about the full process you used to create this.

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I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic

You might also want to check out www.cycfi.com

No special prep, although it still isn't coming out perfect with CF applied to bamboo under a vacuum... It's getting pretty close. The guy behind it is very interesting, and we've had several conversations about our pet projects such as the merits of low-z pickups.

I still need to get around to describing my idea. Hopefully sometime today.