Primitive Archer
Main Discussion Area => Bows => Topic started by: paoliguy on June 23, 2014, 12:46:35 pm
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I finished up an Ash board bow this weekend. 50# plus at 28" it has a glued on handle. After a few full draw shots I hear some distinct pops. I'm sure it's the glue joint failing. Do any of you have any advice as to how I might fix it? I thought of cutting it off or steaming it off and attempting to re glue. Maybe eliminating the handle, reducing the draw weight a bit and keeping it a bendy handle. I thought a couple of other things when it popped but I can't repeat them...
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If it pops off u can glue thin lams to build it back up. The thin lams help it from popping off
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You need fades to keep that handle on. If it pops, its bending. The fades stop the bending before it gets to the handle and pops it.
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I think you've both hit on something. I have always in the past layed up handles and my fades have always been a bit longer too. The handle was for sure bending very slightly, I could feel it.
Thank you both, I knew I would get encouragement to take another swing at it here!
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Like this.
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I had this problem a few times - I've added a lam on the back of the bow that goes past the fades a few inches, that will stiffen up your fade area and keep the handle from bending. Bubby also had a really good solution - add a 16" lam to the belly, then build up your handle with additional lams, then re-tiller since your fades will be stiffer. Depends which surface on your bow is better for Glueing I guess.
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That looks awesome pearl drums!
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Here is an example of 1/8" lams feathered into a limb to build up a glued on handle. This handle will never pop off.
(http://img.photobucket.com/albums/v181/ekrewson/bow%20making/featheringfadesBBO_zps638d4aee.jpg) (http://smg.photobucket.com/user/ekrewson/media/bow%20making/featheringfadesBBO_zps638d4aee.jpg.html)
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Another good example. Fades are second to tiller on my "important list". They can make or break your bow as easy as a poor tiller can.
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I finished up an Ash board bow this weekend. 50# plus at 28" it has a glued on handle. After a few full draw shots I hear some distinct pops. I'm sure it's the glue joint failing. Do any of you have any advice as to how I might fix it? I thought of cutting it off or steaming it off and attempting to re glue. Maybe eliminating the handle, reducing the draw weight a bit and keeping it a bendy handle. I thought a couple of other things when it popped but I can't repeat them...
Will you post a picture form the side so I can see how much fade is not enough? To compare with the ones already posted. I'll show you mine if you'll show me yours :D :D :D This one started to pop off and I filled it with CA. I "seems" to have stopped but I haven't shot it that much. You can see the width of the glue line. It was nice before.
Thanks
Don
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The type of glue you use can mean the difference between a handle that stays on or not. A relatively rubbery glue like titebond 3 is more likely to lift at a fade with a shallow belly lamination, than the same joint glued with urea formaldehyde or a top bowmaking epoxy(not an average hardware epoxy).
Hamish
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The type of glue you use can mean the difference between a handle that stays on or not. A relatively rubbery glue like titebond 3 is more likely to lift at a fade with a shallow belly lamination, than the same joint glued with urea formaldehyde or a top bowmaking epoxy(not an average hardware epoxy).
Hamish
I have to disagree totally, I use almost exclusively tight bond glues and have no issues with handles popping off or laminated bows delamming
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I used West Systems. I've had no problems with it but this handle pop-off seems to be a special case. It seems to be the extreme test for glue and gluing.
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Thanks for all of the great responses. I used Titebond 3 on the handle in question but I think it's more related to the fades like PD said. I tried pulling it again tonight and there is for sure some bend in there. I will post a picture if I can figure out how. Thanks again, I will post an update in a few days.
Mark
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I will post a picture if I can figure out how.
Knowing how to post pictures is pretty much necessary on this site. If I had to explain my questions with just words I'd be lost :-[ :-[ :-[
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Simply putting it,if it bends in the fads and handle area,the handle will pop no matter what glue you use almost every time. The handle/fad area has to be rigid or what you glue on for the handle/fad build up has to bend with the area bending,or pop :)
Pappy
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Glue type is irrelevant. Its all about design. TB3 is fantastic wood glue.
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I agree with Pappy and Pearl. I try not to glue a handle on anything over 64" long unless the wood is over 3/4" thick to start with. Short bows like 54" I may go down to 1/2" but prefer not to.
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Exactly right start with a 3/4 inch board for the belly, glue the handle on top of that and you'll have no problems.
Powerlams are also a great way to stiffen up the handle area and add a bit of colour. Just get the edges paper thin for a good glueline.
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Glue type irrelevant? I wish it was, it would make life even easier.
Titebond 3 is an excellent glue, I never said it wasn't. I said it is rubbery when compared to urea formaldehyde or a proven bowmakers epoxy. The glue line of urac dries hard like glass and is much more rigid than T3.
T3 is however my go to glue for about 90% of bowmaking. I pretty much always use it for gluing lams for limbs, never had a problem either. So many excellent properties: waterproof; easy to use and clean up; cheap. Definitely the best PVA glue I have come across.
I actually agree with most of what everyone has said about building the handle area up with powerlams, or having a thick belly slat or stave in the first place to insure that the fades aren't bending. T3 or most likely any other glue for that matter will work if the fade/handle area is stiff enough to stop bending. I have and still do rely on T3 if the thickness of the handle area is around 7/8".
Think about it... if the fades are not bending then the glue line will be under less stress and therefore is not going to fail. That is more about the design of the fades and thickness of the belly material rather than glue used.
However many pre f'glass era bows have a thickness at the fades of 1/2"-5/8" with multiple lams feathering through the fades and handle and show no signs of lifts despite being heavily reflexed. They were glued up with urac or resorcinol.
You can make a bow with a glued on handle that will flex through the fades or even through the handle and still stay on if you use urac or another glue that dries glass hard. You can even make patches on the fully working part of the limb glued on with urac stay together(not too many glues will let you get away with that). see Dean Torges website he has an excellent article, I think it was also printed in PA mag many years ago.
If Palioguy used urac etc and did nothing else different I would be very surprised if his handle lifted. We wouldn't even be having this discussion.
Hamish.
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Something I haven't been able to get through my thick head. On multi laminated bows the glue joint(it would seem to me) would go through the same stress, maybe even more flexing mid limb than a handle that just barely moves. Why don't they come apart? They obviously don't so I'm obviously missing something. What is so tough about gluing a handle? If the glue joint is stronger than the wood (they all claim that) why don't selfbow handles pop off? Actually I do remember someone posting one.
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Don, I have wondered this same thing a million times. It is much easier to split off an osage with a wedge than it is to split off a glued handle. The only explanation I have is that when it is naturally laminated it bends at the same rate as the wood, when glued we have a straight line where it has almost infinite stress right on the tip when you bend it. Natural wood spreads out some of the load where a laminate offers the stress a very concentrated spot to start lifting. Very often when a handle splits off it will take wood with it.
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I do as Mr. Krewson does on iffy handles. 1/8 lams are the way to go.....I will be trying the adding wood to the back, as you can make a more forward sitting handle that way. :)
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The flite bow I posted last week I used a 7/16 lam and built it up with 1/8 lams, seems to be holding up ok.
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Remember that people will often use a different wood or switch the grain around when gluing on a handle. That likely changes the stress in a glued on handle relative to a handle that is part of the stave.
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I was reading one of Dels old posts and he said he's glued a piece of leather between the pieces of wood to act as a flex joint. Has anyone tried this?
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it still comes down to design, if it bends in the fades it will pop, if your work is poor and the mating surfaces don't match the properties of the glue, it will pop, even epoxies will fail
multiple lams feathered out thru the fades don't pop with tt3 when properly executed, epoxie not nessesary
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There are glues and there are glues, I have never had a handle that didn't pop off back in the old days when I used Two Ton epoxy, on the reverse, I have never had one pop off since I started using urac. Due to a senior moment on the bandsaw, I cut a beautiful stave to about 7/16" thick in the handle, I glued on my thin lams to build the handle up and it is still in place 7 years later.
On thing I always do is orientate the grain on my shims just like the grain on the bow, in other words, no quarter sawn lams and the grain orientation on the lam will be the same as the stave grew on the tree with a back and a belly.
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I do 99percent of my risers with lams. I find I get a better fit(glue joint) and if the design imparts a bit of deflex in the handle area and fades, I can match that with the flexible lams and still get tight glue joints...
Never had a handle pop on me using Urac either. Of course I do use a power lam most times as well, but have done without too.
Most lams are about 1/8th inch maybe abit more.
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There are glues and there are glues, I have never had a handle that didn't pop off back in the old days when I used Two Ton epoxy, on the reverse, I have never had one pop off since I started using urac. Due to a senior moment on the bandsaw, I cut a beautiful stave to about 7/16" thick in the handle, I glued on my thin lams to build the handle up and it is still in place 7 years later.
On thing I always do is orientate the grain on my shims just like the grain on the bow, in other words, no quarter sawn lams and the grain orientation on the lam will be the same as the stave grew on the tree with a back and a belly.
Interesting, what brand, and what set time?? I have never had a problem with Devcon 2-ton slow set...30 minute plus. The quick set is junk! You must, and I mean MUST mix it well.
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I wonder if anyone has consulted with a glue manufacturer about this? It would be interesting to hear their take on it.