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Main Boards => PowWow => Topic started by: glennsea on December 10, 2007, 12:05:00 PM

Title: Tiny Cracks
Post by: glennsea on December 10, 2007, 12:05:00 PM
I have a bow from the late 60's that has tiny cracks in the glass(I am guessing glass) surface all over the bow.  

Is it ok to shoot it like this or do I need to get it fixed and can it be fixed?  Thanks!
Title: Re: Tiny Cracks
Post by: Blackhawk on December 10, 2007, 12:11:00 PM
What happened?  The forum topic says "minimum elk bow weight" and was posted by someone else.  Is my computer scre#ed up again?
Title: Re: Tiny Cracks
Post by: TexMex on December 10, 2007, 12:14:00 PM
does it have tiny cracks  :biglaugh:
Title: Re: Tiny Cracks
Post by: glennsea on December 10, 2007, 12:57:00 PM
I see Tiny Cracks as the title.  Not sure what happened.
Title: Re: Tiny Cracks
Post by: Bjorn on December 10, 2007, 02:44:00 PM
Well if this is the crack thread listen up. Those are known as stress cracks, or compression lines-it means the same and they are common on many '60 bows. As long as there are not too many just go ahead as before. If new ones develop hang it up, or if you get 5 to 6 long ones in any one panel I would quit using it. I have fixed bigger ones with very thin CA. And 'bowdoc' can make them disappear etc. Mainly they are caused by expansion  of the wood in the bow itself over time. Typically not anything more than just plain 'ugly'.
Title: Re: Tiny Cracks
Post by: Orion on December 10, 2007, 02:52:00 PM
Bjorn, I believe you're talking about self-bows right?  On glass laminated bows, superficial "cracks" that run perpendicular to the limb, i.e., across its width, are usually in the finish.  You might notice some milkiness as well.  It's most common just past the fadeouts where the limbs bend the most.  Those usually aren't a problem.  Even the longitudinal cracks, those that run vertically along the limbs, usually aren't much of a problem unless they are large/deep and or there are a lot of them.
Title: Re: Tiny Cracks
Post by: TexMex on December 10, 2007, 03:14:00 PM
Orion,
Would it help any -on the longitudinal- to add some superglue in them?
Title: Re: Tiny Cracks
Post by: Bjorn on December 10, 2007, 03:26:00 PM
Orion; I'm talking about the lines on Bears and others that run length wise and are most often in the fades; but can be in the limbs as well. Selfbows as I understand them have no glass sandwich.
Title: Re: Tiny Cracks
Post by: Killdeer on December 10, 2007, 06:42:00 PM
If the tiny cracks are all over the bow, as glennsea stated, and if they run all different directions, then the finish is "crazing".

You can see the same effect in old china, looking like spiderwebbing or the fracture lines in a broken windshield, where the glass shatters but holds together as a safety feature. A refinish will cure that.

Killdeer
Title: Re: Tiny Cracks
Post by: Orion on December 10, 2007, 11:21:00 PM
Tex Mex, Bjorn.  I'm talking about the same type of longitudinal cracks.  I've never done it, but know folks who have superglued them.  Gets a little messy, but does help hold them together.  The small horizontal stirations and milky stuff I was talking about is what Killy is describing.  I've never seen it all over a bow though, usually just in the portion of the limbs that get the most flexing.  Cosmetic rather than a structural issue. Refinishing does "fix" it.
Title: Re: Tiny Cracks
Post by: Dave Worden on December 11, 2007, 09:33:00 AM
It is my understanding that a few longitudinal  cracks are irrelevant.  Supergluing makes the bow look better but the I believe the bow is safe to shoot if it only has a couple of longitudinal cracks.  One horizontal crack IN THE GLASS however, makes it a wall hanger.
Title: Re: Tiny Cracks
Post by: Killdeer on December 11, 2007, 04:36:00 PM
Orion, I was not talking about those striations. I was talking about a general crazing of the finish that I have seen happen. My old BP Colt did that, and finish popped off in some small places on the riser, in between the cracks. It was just a hard finish that got old and failed.

Killdeer