Has anyone used carbon twill. That would be the 45 layup.
Supposedly does nothing for stiffness but great for eliminating twist in a curve.
Putting it over the glass. Would you subtract the thickness of the carbon out of the core stack.

Following this one.  Have some thoughts but I'd rather hear from them what's been there and done it.

What are your thoughts ?
Have talked to one bowyer that does but I like to find out more before I jump in.

Stabil-kore is not 45* and it works

Max it don't look cool tho 
The 45 stuff will make them rock solid to.

 

Quote from: Crooked Stic on November 06, 2021, 06:30:19 PM
Has anyone used carbon twill. That would be the 45 layup.
Supposedly does nothing for stiffness but great for eliminating twist in a curve.
Putting it over the glass. Would you subtract the thickness of the carbon out of the core stack.

45/45 carbon twill is going to be nothing but stiff. It's mostly used to make rigid panels/parts.
You can get it pretty thin though for cosmetic (cool look) .008"

Curious about the process you will use to put it over the glass?

Quote from: Mad Max on November 07, 2021, 02:25:57 PM
Stabil-kore is not 45* and it works

I used stabilcore and very thin 0.008 45/45 weave.
The 45/45 does a LOT more to stiffness than the stabilcore.

Truth about the 45/45

Not quite sure, are you going for looks or performance. I guess you can get very thin twill to go over glass for looks, don't think it would do much if anything for performance since your putting on another glue line with something that thin. You can get the thicker carbon twill specifically for backing instead of glass for performance and looks.

I think I would be putting the carbon under the glass for a few reasons. First it would make sense to put the more elastic glass on top of the stiff/ brittle carbon, which would also give it the coveted look of depth and its going to be a b*#@h to get a smooth surface if that carbon is on top of the glass unless  you are doing an infusion or laying it up on a smooth, prepped tool surface.

All the super curve guys do it. If you want performance you need the uni for stiffness also
I am getting .020 twill from Rosewood. Happen to know a bowyer using it on all his curves for lateral strength over glass.

Quote from: Flem on November 09, 2021, 12:32:23 PM
I think I would be putting the carbon under the glass for a few reasons. First it would make sense to put the more elastic glass on top of the stiff/ brittle carbon, which would also give it the coveted look of depth and its going to be a b*#@h to get a smooth surface if that carbon is on top of the glass unless  you are doing an infusion or laying it up on a smooth, prepped tool surface.

I m wondering if it  is 45/45 weave or pre preg?

I would be inclined to put it under the glass as well.  Also wondering if it's really needed front and back 🤔

The carbon look does sell well with a specific group of archers I think.

It is not prepeg. One side is shinny. Some sort of resin I guess. the glue side is flat black and actually pretty course . The lateral twist control is what I am after and prolly one strip would be good on the belly then could veneer the front. For now I am gonna use front and back.

I've made a few bows with the .040, 45/45 layered carbon weave made just for the backing, instead of backing with glass, I'm wondering if putting .020 carbon weave over  glass has more benefit unless the bow is already done and you want to add it on, I've not tried that yet, if you do it let us know how it turns out please

I have built a pretty hooky Recurve with 0.02 45/45 Carbon in top of 0.03 Glass in Back and belly.
The Result was very torsional Stiff.

The thicker .040 layerd 45/45 carbon weave just being used for backing instead of glass has good torsional stability by it's self, so not sure of benefit of adding .020 on top of glass on a new build, witch makes the glass part of the core and perhaps more glue lines. There's all sorts of designs and layups that can be used to make a bow, keeps it interesting.

Carbon, that replaces Glass usually has at least 50% UD fibers in it.
Mostly it's about 50:50 UD and 45/45 or the 45/45 ist more Like a cosmetic layer and is more Like 20:80.

Quote from: Crooked Stic on November 09, 2021, 09:54:32 PM
It is not prepeg. One side is shinny. Some sort of resin I guess. the glue side is flat black and actually pretty course . The lateral twist control is what I am after and prolly one strip would be good on the belly then could veneer the front. For now I am gonna use front and back.

Stic, did you cut that from a roll or purchase like that?

Where did you source it?