Clear Glass

[LongStick64]

What causes vertical lines to appear on clear glass laminate bows ? Should I be concerned about it ?

[walkabout]

ive got an old recurve with a bunch of lines on the glass, i think its mostly stress in the finish.

[Jason Scott]

If your talking about long milky streaks running the length of the glass then those lines come from the factory and pose no quality or safety issues. Only appearance issues over dark veneers. I have one bow where you can barely make out the grain of the wood under the milky streaks. I've heard that clear glass lately has gotten better with less streaks. Some wharehouse suppliers may still have stock left over with the streaky galss and you may see this for a while. I got some from 3r three weeks ago and it was ok. It's probably safe to ask your supplier if the lot of glass they have has been reported to have the streaks. You really can't see them until after you remove the tape. Or you could wet the glass and lay it on something dark and try to see before glueup. It's a gamble with clear glass nowadays.

[kennym]

If these have appeared recently and were not there before,you might want to have the bowyer(or a bowyer) look it over.

Like Jason said,on new ones,no matter how closely you look the glass over,it will still bite ya once in a while. Part of dealin with clear glass.

[nchunter]

I don't know if it's true but a bowyer told me that if you look at the glass under a black light before you use it in your lay-up, if there's any streaks in it they'll show up in under black light.

I know in the plastic film industry they use black light to see imperfections before printing on the film.  

Worth a try, since you can buy a black light bulb from the Home Improvement stores for $5 or so.

[GREG IN MALAD]

This is the way it was explained to me. Gordon Composite buys their fiber from a vendor. The fiber has a specified tolerance for hardness, if it is on the soft end of the tolerance it absorbs the resin and makes clear glass, if it is on the hard end of the tolerance it won't absorb the resin and we get streaky glass.

[Mike Mecredy]

I no longer even use it.  The stuff's too frustrating for me.