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Main Boards => The Bowyer's Bench => Topic started by: buckeyebowhunter on April 09, 2020, 06:06:13 PM
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Was working on my most recent set of limbs today and noticed this very small pinhole at the end of my limb wedge where the laminations meet the wedge. The hole is not on both sides of the limb but just this one side. I got to wondering how I'd not noticed this before and checked to see if they were in my previous set of limbs (made them with bingham's wedges) and there was some of these holes in the same spot on them as well.
I am wondering if this is due to my wedges not being faded enough? Or a low spot/dip in my form at that area creating a void in pressure? Have you guys experienced this before and if so did you have a remedy. Thanks in advance. I took a picture hopefully you can see what I'm describing they are pretty tough to see. Thanks again and hope everyone is staying safe and doing well.
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I had this issue on my last set of TD limbs (also my first, so take my comments with a grain of salt...). In my case, it was the wedges not being faded enough, but I also know that it can be caused by a lack of pressure as well. The lack of pressure and the wedges being faded go hand-in-hand, if they aren't faded enough the hose can't contour the limb in the form. Adding wedges in between your hose and compression layer (if you are using one) can help to get more pressure on the fades. See Kenny M's build-along here: https://www.kennysarchery.com/bow-build
About a third of the way down he shows what I am talking about. Also, you can get this issue if there is too big of a gap between the two halves of your form.
Again, I am a novice so I wouldn't take anything I said as gospel. Maybe some of the more experienced fellers in here can chime in.
PS Superglue in those holes will fill them no problem.
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I've bought wedges from Bingham's before but I always feather the fadeouts myself and do a dry run to make sure they're right. If I can see any light through them I work the wedge until its gone and its tight. I check all of my wedges the same whether I purchase them or make them myself.
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Thanks for the replies guys. I will be doing some dry runs to check them from here on.
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Those look like they are a little bit beyond the tip of the fade. However, im looking at the pic on a phone so that's not ideal.
The glue lines look pretty good on both sides of the holes. It has me wondering how deep they are.? It doesn't seem like with good glue lines on each side that there was a pressure failure in that little spot.
Maybe not enough glue? Lams just tiny bit too narrow?
Just wild ass guessin.
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Mike I will say this for sure, I used plenty of glue. I have always used probably more than I need to and get plenty of squeeze out. So we can rule that out. Just puzzles me that it's not showing up on all limbs, as they are all the same form. Going to glue up a new set of limbs next week and see what happens.
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Maybe the wood gassed out a bit and caused bubbles in the squeeze out? Then when you ground it down you only ground halfway through the bubble?
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It's very strange. I'll be following.
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I've had what seemed to be gasout under clear glass that I think was from cleaning with acetone or alcohol and not letting it dry/evaporate enough. Since then I don't clean with either and no more problems. Knock on wood!! :o
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This is a swag but it looks like tip of wedge has slide to side slightly and you have glue with a bubble there . I’m thinkin if you grind a tad deeper you will clean it up .
Maybe,,, :)
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Kenny, thank you for the advice. I'll try it tomorrow. Nothing to lose on these limbs. They actually are the limbs I glued with BP glass and came in way lighter than anticipated so I can't give them to the person they were intended for and may end up making them into youth limbs.
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Hope that’s it ! :thumbsup:
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I think it is a bubble to. You can try grinding it a bit more or clean it out really good and force some smooth on it it.
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Ended up grinding some off and almost eliminated them completely. Filled the remaining little bit with some CA and you can hardly tell they're there. I'm not sure if this has anything to do with the problem but I noticed that the limbs that these showed up on were all made with wedges of actionwood. So maybe it's the wood? May try walnut on the next set and see what happens also going to feather fadeouts more.
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I’ve had that happen a few times but it was on the outset of the lams so it ground off, if there’s a pin hole just get it close, fill it like you did, then continue finishing... just don’t want dry spots etc and have a limb fail so definitely shoot it a bunch before you get too far finishing.
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Hard to tell for sure since the photo is blown up but part of your problem may be the that laminations on top of the wedge are a bit thick and are having trouble bending into that area where the glue is thick, causing the bubble. Maybe this would be avoided with three thinner lams on top vs two.
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Hard to tell for sure since the photo is blown up but part of your problem may be the that laminations on top of the wedge are a bit thick and are having trouble bending into that area where the glue is thick, causing the bubble. Maybe this would be avoided with three thinner lams on top vs two.
Definitely
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What about more pressure in my air hose? Currently running 60psi.
*The glass is .043 and the top wood lam is .050.
Waiting on materials to experiment with the next set of limbs. Thanks again for the help fellas.
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If it's a pressure problem, then at 60 psi, it is probably a form fit problem.
You could try it as a topless form and see how that goes.
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Could put a few layers of duct tape on the top of the form at the point where the bad glue line is and see if more pressure in the area helps.
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I would be sure the next wedges were thin enough to see light thru on the very end. Make a dry run and check if you see light thru that area.Ideal is your hose dog bone shaped from end view
. If you got light then you need to reduce the space there.
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Did you run a square across your forms to see if there is a dip . You will want to put some wood pieces (2" by what ever width you bow is ) above your hose where the end of the fade out is make it tight before you blow up your hose, this will create more pressure at that point .
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Thanks again for all the tips guys. Still waiting on glass :banghead:
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It won't make any more pressure. It will make what pressure you have press tighter in that area.
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I've had it happen from time to time over the years. I've always made my own fades but sometimes I epoxy a piece of glass on the flat side and then grind that to a feather thin edge. It seems to be easier to get it see through thin and it's a little tougher than wood.
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That looks nice Brad :thumbsup:
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same thing