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View Full Version : Stabilizing a crack



elkslayer4x5
02-22-2011, 10:52 AM
While preparing for my Cougar lll Elite cam change, I found that I've got a crack at the bottom of the cam fork, about 5/8" long, on the front side ( target side ) of my 5H 08 carbon limb. I say 08 because it was a bottom limb and has the sticker on it, ser# 08. Since its going to be a nitrous shoot thru bow, Im wondering if I can stabilize the crack/splinter by gently sperading it open and letting an epoxy ooze into it and then clamping it togather again. I can see movement with a magnifing glass while twisting the forks, but those forks won't be twisting any longer. Tell me what you think. What type of epoxy or super glue would work best. :)

http://img.photobucket.com/albums/v728/deast-lr/Crack.jpg

gibson 787
02-22-2011, 10:58 AM
I definitely would get those limbs replaced.

scepterman30x
02-22-2011, 11:02 AM
While preparing for my Cougar lll Elite cam change, I found that I've got a crack at the bottom of the cam fork, about 5/8" long, on the front side ( target side ) of my 5H 08 carbon limb. I say 08 because it was a bottom limb and has the sticker on it, ser# 08. Since its going to be a nitrous shoot thru bow, Im wondering if I can stabilize the crack/splinter by gently sperading it open and letting an epoxy ooze into it and then clamping it togather again. I can see movement with a magnifing glass while twisting the forks, but those forks won't be twisting any longer. Tell me what you think. What type of epoxy or super glue would work best. :)

http://img.photobucket.com/albums/v728/deast-lr/Crack.jpg

BTW the target side is the back of the bow...more for enlightenment and not criticism.:D

archerx7
02-22-2011, 11:24 AM
Probably be a much better idea to get them replaced.

ElkSlayer
02-22-2011, 11:51 AM
you got a good picture of it ;) and the responces we knew already.:rolleyes:

it was a used bow when he got it. any other ides on a fix, it is only a small crack..Bow will be set up X system, no torque on limbs.. We would like to swap it out for a new one, but no warrenty on a used bow..

So lets all think out side the box a minute.. Any one Ever try to fix something like this?

gibson 787
02-22-2011, 12:25 PM
Any one Ever try to fix something like this?

Never tried, but thought about it and never heard of any attempts. No torque is definitely a plus, so the only way to find out is to give it a go using the strongest epoxy available. You will need to apply heat and that needs to be done carefully so as to not weaken existing lamination joints. Also, after glueing the crack, some glass matting could possibly be used to strengthen the area.

Have you priced a new set of limbs, I don't think they would be much over $150.

Good luck.

Arrow Splitter
02-22-2011, 12:30 PM
What type of epoxy or super glue would work best.



:eek::eek::eek::eek: You're scaring me!!

elkslayer4x5
02-22-2011, 01:13 PM
It more splinter than crack, doen't carry through the limb, just that surface. I just knew someone would catch me with which is the front of a bow! Can't slip nuthin past you guys. :o

Arrow Splitter
02-22-2011, 01:23 PM
It more splinter than crack, doen't carry through the limb, just that surface.

I feel slightly better now.:D:D

gibson 787
02-22-2011, 01:29 PM
doen't carry through the limb, just that surface.

It's likely one lamination that's cracked.

ElkSlayer
02-22-2011, 01:46 PM
:D
I just knew someone would catch me with which is the front of a bow! Can't slip nuthin past you guys. :o

should have just called it what it was, not simplified it.;) :D

bfisher
02-22-2011, 05:52 PM
BTW the target side is the back of the bow...more for enlightenment and not criticism.:D

I used to correct guys with this statement, too, but gave up. Our younger generations know very little about bows, terminology, or history. I made a comment like this once on AT and got slapped on the wrist for my efforts.

NuttyNative
02-22-2011, 06:42 PM
I used to correct guys with this statement, too, but gave up. Our younger generations know very little about bows, terminology, or history. I made a comment like this once on AT and got slapped on the wrist for my efforts.

That happens alot over there (AT) people just trollin for stuff like that. If I were to try and fix that, I would use carbon fiber resin, at the very least mix ground up carbon fiber to an epoxy resin. That works in high tech R/C cars, very durable.

elkslayer4x5
02-22-2011, 06:46 PM
Never tried, but thought about it and never heard of any attempts. No torque is definitely a plus, so the only way to find out is to give it a go using the strongest epoxy available. You will need to apply heat and that needs to be done carefully so as to not weaken existing lamination joints

My thought was to use gravity and the hot sun and let a slow setting carbon fiber resin settle into that lamination crack to seal it off and prevent any further movement. Any other ideas on how to inject the resin into the split? :confused:

gibson 787
02-22-2011, 07:47 PM
My thought was to use gravity and the hot sun and let a slow setting carbon fiber resin settle into that lamination crack to seal it off and prevent any further movement. Any other ideas on how to inject the resin into the split?

I think I would use a hair dryer for heat which would really thin the epoxy and gravity would certainly let it seep into the crack. Wheather it seeps in enough is the problem. I would then place a 1/2" high piece of wood the same length as the crack over the crack, then bind it with the limb as tight as possible with 1" strips of inner tube rubber or similar. NB. You will need to put a thin piece of plastic sheet, or something that won't bond to the glue, between the wood and the bow so you won't end up glueing the wood to the bow. Reason for the wood is to exert as much downward pressure on the crack as possible.

Had another thought. Go to www.3riversarchery.com which is a traditional shop, and put the task to them, they certainly have the right glues for the job and would likely be able to give you a few tips as well.

Hope this helps.

Spiker
02-22-2011, 08:12 PM
I think I would use a hair dryer for heat which would really thin the epoxy and gravity would certainly let it seep into the crack. Wheather it seeps in enough is the problem. I would then bind the limb as tight as possible with 1" strips of inner tube rubber or similar.

Had another thought. Go to www.3riversarchery.com which is a traditional shop, and put the task to them, they certainly have the right glues for the job and would likely be able to give you a few tips as well.

Sorry for getting off the track here but I just looked at 3rivers site and I have just got to order a couple of those 'whistling points'.
(Maybe they should be posted on the thread about usless junk to spend our money on...)
I gotta have one tho - just to mess with people next time I go to a shoot...

As far as the op - I'm all for fix-it-yerself and there is some good suggestions here but - I just dont think I would shoot very well knowing that I have a possibly broken limb that I patched up.

gibson 787
02-22-2011, 09:53 PM
I gotta have one tho - just to mess with people next time I go to a shoot...

LOL! yeah, thought about it myself :D

elkslayer4x5
02-23-2011, 12:24 AM
I think I would use a hair dryer for heat which would really thin the epoxy and gravity would certainly let it seep into the crack. Wheather it seeps in enough is the problem. I would then place a 1/2" high piece of wood the same length as the crack over the crack, then bind it with the limb as tight as possible with 1" strips of inner tube rubber or similar. NB. You will need to put a thin piece of plastic sheet, or something that won't bond to the glue, between the wood and the bow so you won't end up glueing the wood to the bow. Reason for the wood is to exert as much downward pressure on the crack as possible.

Had another thought. Go to www.3riversarchery.com which is a traditional shop, and put the task to them, they certainly have the right glues for the job and would likely be able to give you a few tips as well.

Hope this helps.

I had planed on using lightweight plastic between the limb and the heavy webbing I'll use to isolate the limb from the clamps, was going to coat the plastic with a release agent, vasoline should work. I'll see the 3rivers has to say. Which is a funny coincidence, the nearest archery shop to me is in Dos Rios. :)

alex
02-23-2011, 12:54 AM
Elkslayer, i think you should take the smallest drill and make a tiny hole at the beggining of the split/crack - no more then a mm deep i guess. (I'm not sure about this, but that's the way to prevent a breakage when you have a crack on a circular saw.) Then you can fill it with epoxy. Another thing i'd do is to wrap the limb with some kind of tape (camo one would be fine) - not to save the limb from breakage, but to save you if it explodes.

alex
02-23-2011, 01:00 AM
Sorry for getting off the track here but I just looked at 3rivers site and I have just got to order a couple of those 'whistling points'.
(Maybe they should be posted on the thread about usless junk to spend our money on...)
I gotta have one tho - just to mess with people next time I go to a shoot...

As far as the op - I'm all for fix-it-yerself and there is some good suggestions here but - I just dont think I would shoot very well knowing that I have a possibly broken limb that I patched up.

Scott, do you plan using the whistling points with a compound or with a recurve? I've made some and strangely they worked better with a recurve, don't know why, guess the speed of the arrow is too much with a compound bow.

bfisher
02-23-2011, 04:00 AM
First, I would recommend replacing the limbs, but..........

I like the idea of using a small drill to stop the crack from spreading. Being old school how about one of those old limb reinforcing buttons that used to be used in the forks of a lot of bows? This would likely give the limb tips some torsional support.

elkslayer4x5
02-23-2011, 09:19 AM
First, I would recommend replacing the limbs, but..........

I like the idea of using a small drill to stop the crack from spreading. Being old school how about one of those old limb reinforcing buttons that used to be used in the forks of a lot of bows? This would likely give the limb tips some torsional support.

Would you happen to have a photo of what you're refering to? :) I'd be a bit nervous drilling a hole, seems that would encourge the piece to break off. :eek:

bfisher
02-23-2011, 09:27 AM
Would you happen to have a photo of what you're refering to? :) I'd be a bit nervous drilling a hole, seems that would encourge the piece to break off. :eek:

No pic, but what I'm saying is that you can find the end of the split. It has to spread longitudinally down the limb. At the end of the split you drill a small hole which should keep it from continuing farther down the limb. If it doesn't then the limb was going to be scrap at some point in time anyway.

My concern is that with a crack like that the vibration from shooting is going to make it crack/split futher. Like I said, maybe one of those old style buttons in the bottom of the fork would help.

gibson 787
02-23-2011, 11:14 AM
And yet another thought.

If repairing the limb doesn't work out, I know Dave Barnsdale from www.barnsdalearchery.com will make you custom limbs for $150. Dave has an excellent reputation for making a great product.

bbjavelina
02-23-2011, 11:39 AM
There are "super glue" type wicking glues available. At least one used to be marketed by Loctite. With a thin bead placed over the crack, they actually wick down into the crack and bond it back together. Since that portion of the limbs flexes very little they may work at least for awhile.

Obviously you know the long term fix.

Best of luck!

Hutch~n~Son Archery
02-23-2011, 12:05 PM
There are "super glue" type wicking glues available. At least one used to be marketed by Loctite. With a thin bead placed over the crack, they actually wick down into the crack and bond it back together. Since that portion of the limbs flexes very little they may work at least for awhile.

Obviously you know the long term fix.

Best of luck!

Super glue does crack in cold weather! Super glue becomes brittle in long term use and in cold.

Hutch:cool:

Spiker
02-23-2011, 02:19 PM
If you add up the time you've spent pondering this and payed yerself - you would be halfway to a set of Barnsdales...

elkslayer4x5
02-23-2011, 04:41 PM
LOL, more like 3/4 into a 2nd set, I've been mulling this over for a while. I took gibson 787's advise and found this resin at 3Rivers.com. Think it will work?
http://www.3riversarchery.com/Kwick-It_c0_s0_p0_i4451X_product.html

Gallagher N.B.
02-23-2011, 04:46 PM
I got it duck tape and J.B. Weld lol. cheap and affective.ok ok i say replace .

gibson 787
02-23-2011, 05:12 PM
LOL, more like 3/4 into a 2nd set, I've been mulling this over for a while. I took gibson 787's advise and found this resin at 3Rivers.com. Think it will work?
http://www.3riversarchery.com/Kwick-...X_product.html

Did you ask them if it's as suitable to use with glass as it is for wood? I found that the resins that come in 2 parts are generally the strongest. Also did you explain to them what your project is, they're known to be really helpful with their customers, I can vouch for that.

Dave

Rockyhud
02-23-2011, 08:09 PM
I'll vouch for 3Rivers customer support being very good. When I was buying my Grizzly broadheads and screw-in adapters I called them and got some very good advice that enabled me to glue these pieces together about as perfectly as could be done. They spin-test very well and fly great. Just thought I'd pass on my two cents and experience with 3Rivers. BTW good luck with your repair project. And be watchful and careful afterward. We'd hate to hear about it causing anyone harm.

elkslayer4x5
02-23-2011, 08:45 PM
Did you ask them if it's as suitable to use with glass as it is for wood? I found that the resins that come in 2 parts are generally the strongest. Also did you explain to them what your project is, they're known to be really helpful with their customers, I can vouch for that.

Dave

Well, no. I confess, I just read the text, the blue is for dis-similar materials. But I did email their cs including this thread, and my photos, and my plea for their help. :)

alex
02-24-2011, 12:56 AM
I still think that drilling a tiny hole is a good idea (and now when Barry is with me i feel more confident :D ) If you just use superglue or epoxy enough of it won't penetrate in this microcrack, so at least you must prevent the split going further. And i'm sure that a 0.5mm hole deep 1-1.5mm won't hurt the limb any more then the crack.

archerx7
02-24-2011, 04:45 AM
First, I would recommend replacing the limbs, but..........

I like the idea of using a small drill to stop the crack from spreading. Being old school how about one of those old limb reinforcing buttons that used to be used in the forks of a lot of bows? This would likely give the limb tips some torsional support.


I still think that drilling a tiny hole is a good idea (and now when Barry is with me i feel more confident :D ) If you just use superglue or epoxy enough of it won't penetrate in this microcrack, so at least you must prevent the split going further. And i'm sure that a 0.5mm hole deep 1-1.5mm won't hurt the limb any more then the crack.

I wasn't going to suggest this, but the shop I worked at many years ago was owned by an older gentleman that started shooting before compounds were invented. He had actually done this also when new limbs weren't an option, he would drill the hole at the very end of the crack all the way through. The round contour of the hole supposedly prevents the crack from continuing on down the limb. Not sure if this will work as the crack on your limb is not centered, it appears to be offcenter. As Barry suggested, use a limb reinforcement button of some type also. I really can't understand why manufacturers got away from using these in the 1st place as most limb failures start at the fork.

elkslayer4x5
02-24-2011, 07:58 AM
I wasn't going to suggest this, but the shop I worked at many years ago was owned by an older gentleman that started shooting before compounds were invented. He had actually done this also when new limbs weren't an option, he would drill the hole at the very end of the crack all the way through. The round contour of the hole supposedly prevents the crack from continuing on down the limb. Not sure if this will work as the crack on your limb is not centered, it appears to be offcenter. As Barry suggested, use a limb reinforcement button of some type also. I really can't understand why manufacturers got away from using these in the 1st place as most limb failures start at the fork.

Like the pricipal of not using square windows in airplanes. 3 River Archery Cs emailed back that the 'Kwick-it' Red is the only glue that would work on this type of splinter. This hole doen't need to go compleatly thru, just thru the lamination?

archerx7
02-24-2011, 09:54 AM
Like the pricipal of not using square windows in airplanes. 3 River Archery Cs emailed back that the 'Kwick-it' Red is the only glue that would work on this type of splinter. This hole doen't need to go compleatly thru, just thru the lamination?

If I understood my old mentor correctly, the hole goes all the way through, if not the crack can continue on the other side and will eventually reappear on the side the hole started from. Make any sense ?

If you look closely at your pics, it appears the crack is all the way through at the fork, probably just a matter of time before it appears on the other side of the limb. All the more reason to stabilze the fork with some kind of reinforcement button.

ElkSlayer
02-24-2011, 10:23 AM
Now why did'nt i think of that...:o drilling a hole at end of crack is how you fix cast iron.( heads/blocks etc).. they have a good point, & and Barry hit it right on the nose... old school limb reinforcement buttons.. feal a bit silly for not thinking of them.. It is a clamp that sits in bottom of limb fork. ole lynx has them. (Ed's ole bow)... this damn head cold wont go away.. snow last night dont help eather..:eek:

alex
02-25-2011, 03:08 AM
We have a couple of circular saws for the table saw that are fixed like that ... and i still have my eyes and limbs ;)

elkslayer4x5
02-25-2011, 06:50 AM
If I understood my old mentor correctly, the hole goes all the way through, if not the crack can continue on the other side and will eventually reappear on the side the hole started from. Make any sense ?

If you look closely at your pics, it appears the crack is all the way through at the fork, probably just a matter of time before it appears on the other side of the limb. All the more reason to stabilze the fork with some kind of reinforcement button.

I've looked really closely, and the crack doesn't go all the way thru the forks, I've marked where the crack/splinter stops top and bottom, on the inside of the forks, it appears to stop at the laminatinon.,
Any idea on how large a hole I need to drill to check the progress of this crack and once I've drilled thru the limb, should I fill the drilled hole with the red Kwick-it?
http://img.photobucket.com/albums/v728/deast-lr/Crackmarked.jpg