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Main Boards => The Bowyer's Bench => Topic started by: AndyTurner on November 09, 2020, 07:11:46 AM
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So I’ve been having a look at BearPaws website and they sell two types of Carbon laminate. Stable core and Power Carbon.
Does anyone have experience with this stuff?
Is there a common layup? E.g. 2XPower carbon & 2XStable core?
Do you still use Fibre glass for the belly & Back or does the Carbon fibre replace this?
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Stabile core is used to provide torsional stability. It is a 90 degree carbon weave about .o15 thick. It is flexible and without resin. Easy to work with and is easily cut with scissors. It takes on it's stabilizing properties when glued into the lay up.
I'll leave the carbon question to those who use it.
A picture of stabil core
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No first hand experience here. I don't know of anyone making carbon back or belly laminate. Bearpaw's are both core additions.
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This subject comes up here every now and then. I don't think you will find your answer here. ;)
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why do you want to use carbon and what will you be using it for??
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Well, moving from “just wood” to “fibre glass and wood” felt like a big step forward. CF intrigues me.
Bodnik provide a 30 year transferable warrantee on their bows which for me is phenomenal. I believe for their Ghost bow they say you can even leave it strung!!!
Now that for me says they must know how to make bows!!!!
They also sell BearPaw CF for making bows. I’d love to know how they use it!
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There are American bowyers using carbon but I'm not sure where they get it. Probably not from Bearpaw.
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i would do glass bows for a while until you get your design wired and in the meantime educate yourself on carbon... after you are satisfied with your design then try carbon... from what i hear carbon can be difficult, brittle and expensive... those guys that are successful at building carbon bows may have a few tricks up their leave, which could take years of working out the bugs... I also hear the rewards are not that great with carbon... carbon is a lot stiffer but glass is a lot tougher...
just my 2cents...
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In my experience, carbon limb bows were noisy.
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Hey guys,
thank you for all your replies. It’s much appreciated.
Best regards,
Andy
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The Rosewood Shop is or was selling carbon. The same stuff Dale Stahl was selling. I have no personal experience with it.
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I always thought Stable core is woven glass? And it would be better with 45 degree layup.
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Stabil core is for torsion stability, there are different types of carbon lay ups, what you saw on the website I believe is unidirectional carbon used as a core and about .015 and binghams has it in .020 it's not used on the back or belly, that should be layerd woven carbon at a 45 degree weave usually around .040. I've used it for the back only with bow glass on the belly, some use the carbon on the belly also. Not easy to find the layerd weave but it is available a few places but you have to check around and ask for it. If you want to experiment it will work with I would say any glass designed bow using a similar core, its much more expensive than glass but with a good design can work really well which may take some tinkering. JMHO.
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We have several sponsors on here that make carbon bows. Morrison, Javaman and Zipper to name a few. They would most likely give you any info you need if you contact them.
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Well, moving from “just wood” to “fibre glass and wood” felt like a big step forward. CF intrigues me.
Bodnik provide a 30 year transferable warrantee on their bows which for me is phenomenal. I believe for their Ghost bow they say you can even leave it strung!!!
Now that for me says they must know how to make bows!!!!
They also sell BearPaw CF for making bows. I’d love to know how they use it!
30yrs sounds impressive until you consider that there are hundreds, if not thousands of laminate bows made
in the 50's, 60's and 70's that are still in use.
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I just remembered reading about the laminate Buemaker uses. Exel of Finland. Too bad you guys bailed out of the EU, although you might still be able to get their products ;)
Looks like they have carbon fiber laminates for back and belly surfaces
https://exelcomposites.com/wp-content/uploads/2020/06/EN_Exel-Archery-Laminates_Datasheet-2017.pdf
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Now that’s exactly the sort of thing I’m after. Will look properly tomorrow but looks like hot stuff!
I’ve been searching the web looking for data sheets on Gordon glass today. I know it’s not CF but I’d like to know the numbers to compare. Couldn’t find anything. Does anyone have one for UL and ULS?
Thanks
Andy
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"The minimum quantity for standard archery widths is 2000 meters/laminate type."
That's 1093 72" pieces :o
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Forget getting any info for "Gordons", they were bought by a large multinational corporation, PolyOne and have been eliminating the Gordons website slowly for a number of years now.
I listed some info I had for Gordons in a post long ago. Don't ask when.
By the way, Gordons does make CF laminates, but nobody sells it.
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Now that’s exactly the sort of thing I’m after. Will look properly tomorrow but looks like hot stuff!
I’ve been searching the web looking for data sheets on Gordon glass today. I know it’s not CF but I’d like to know the numbers to compare. Couldn’t find anything. Does anyone have one for UL and ULS?
Thanks
Andy
Attached is a pdf of Gordon's composites info, current as of April 2020.
Mark
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Morrison even sells twill carbon on their website.
https://www.morrisonarchery.com/shop-4
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If someone is planning on buying carbon fiber fabric or tapes, you might be better off buying from a specialty outfit. I was looking on Morrison's website. They are selling 1.75" carbon twill tape for $28.75 a yard. Composite Envisions sells the comparable product in 3" width for $2.89 a yard
https://compositeenvisions.com/composite-reinforcement-fabrics/carbon-fiber-reinforcements/tapes/
Now that’s exactly the sort of thing I’m after. Will look properly tomorrow but looks like hot stuff!
I’ve been searching the web looking for data sheets on Gordon glass today. I know it’s not CF but I’d like to know the numbers to compare. Couldn’t find anything. Does anyone have one for UL and ULS?
Thanks
Andy
Attached is a pdf of Gordon's composites info, current as of April 2020.
Mark
Nice find Mark! I have been looking for that info from PolyOne, but had no luck.
Gordons UL and ULS are 70% epoxy!
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Nice find Mark! I have been looking for that info from PolyOne, but had no luck.
Thanks. I got it by emailing PolyOne with questions. It took a while, but I eventually got a reply from their national archery accounts manager with this pdf attached. The guy seemed like a serious archer and experienced bow hunter who knew his product very well.
Mark
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You guys are officially faster than PolyOne and Avient! I emailed them yesterday morning.
Do you also have a data sheet on their Carbon?
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Its right there on that PDF, its the GC-70-UCL
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Sorry I havnt had a chance to read it yet
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I just remembered reading about the laminate Buemaker uses. Exel of Finland. Too bad you guys bailed out of the EU, although you might still be able to get their products ;)
Looks like they have carbon fiber laminates for back and belly surfaces
https://exelcomposites.com/wp-content/uploads/2020/06/EN_Exel-Archery-Laminates_Datasheet-2017.pdf
Am I missing something?
1. There is no compression data for any of their products. I know people Generally favour FG for Bellies but some people successfully use CF for belly’s e.g Border. Also do all the FG products behave the same in compression?
2. There is no 90degree data for some of their products. I’m guessing unidirectional products arn’t designed to provide lateral stability but how can you quantify the advantage of the ones that do? The unidirectional stuff must have some lateral properties. They can’t be 0.
I have emailed them. If I get a response I’ll post data.
Thanks
Andy
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No 90deg data for the unidirectional laminates. Would seem to be a moot point.
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Well it’s all about gains & trades right?
A. If you only get a 25% gain in lateral stability then you might not bother.
B. If you get a 95% gain in lateral stability then it justifies the weight gain.
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What style bow are you going to build, Andy?
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What style bow are you going to build, Andy?
Some sort of Hybrid curvy thing. Pic of form attached.
What I would really like is some general advice on working with composites. I posted this in another thread. What do you think?
When building a composite bow, do you use the data sheets to try and build a balanced spring? For example,
GC-70-ULZ has a Tensile strength of 243000PSI. I’d use this for the Back.
GC-70-ULS has a Compressive strength of 119000PSI. I’d use X2 strips of this on the Belly giving 238000PSI
This would provide
243000 working against 238000
This in my "simple head" would give you a "reasonably well Balanced Spring".
Thanks,
Andy
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Ive never seen the ULZ for sale, only the UL and ULS. You have a source over there?
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Ive never seen the ULZ for sale, only the UL and ULS. You have a source over there?
No just saw it on their data sheet so assumed it would be available
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I think this was back in the 60's
(https://i.imgur.com/ex9Bm4a.png)
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Actually 3M started making Scotch-Ply in the 50's. It was made from woven material, compression molded.
Some of those old bows you see with the woven pattern, but not embossed, are most likely Scotch-ply.
I don't think anybody made unidirectional laminates suitable for our use until Gordons started.
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I don’t know why Gordon’s are still using E-Glass (originally for electrical parts hence E). Structural glass (S-Glass) is significantly better in tension & compression. It’s been around for years.
It’s on the data sheets that someone else posted but doesn’t seem to be available.
It’s the ULZ stuff.
Any ideas?
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S-glass is significantly more expensive than E-glass. If you want somebody to start selling it in a retail setting, you will have to create a demand for it.
If you really want some serious performance from your composite bow, you need M-glass on the back and S-glass on the belly.
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If you really want some serious performance from your composite bow, you need M-glass on the back and S-glass on the belly.
😂😂😂😂 This is the email I just got from PolyOne. I give up! 😂😂😂
Yes – the S-glass is very special as the strain I about double of e-glass. But the cost is 7-10 times more per pound. And it is poor in compression.
Most limbs are made of GC-67-UB and possibly have a GC-70-UL laminated/bonded to it if the limb fails etc.
It is tricky business. A lot of dynamic forces and modeling questions.
We do not design limbs or really have any part in it. We just manufacture the composite and sell it to Bow Builders/OEM’s.
I do not know the scale of your project. Our minimum order quantities are 1000 pieces. So you will probably have to go to a distributor or something. www.binghamprojects.com is a good starting point.
Thanks
Rob Loveland, PE
Director of Engineering, Gordon Composites
Avient Corporation
Office: +1 970-240-2234
Mobile: +1 970-640-7310
Web: www.avient.com
Avient Corporation formerly PolyOne Corporation
2350 Air Park Way, Montrose, Colorado, USA 81401
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Thats why some bowyers make their own laminates. That and the colors available are plain and uninteresting.