Crystal STILL cracking?!?

[MarkJM]

For some reason, my crystal just keeps cracking!!! I dont know why either?? I KNOW my pot is not warping, it just keeps cracking in the SAME exact spot everytime I try to glue it togother, about half way through the gluing stage, it'll crack. I am using GOOP to glue the surface

have tried the exact same piece of wood for glass and slate and the pots turn out fine. no cracking and they sound great. Any reasons why my crystal would keep cracking? And if it doesnt crack the call sounds hollow and terrible.

any help guys? Also I am making the rim a little bigger than my surface so it has plenty of play

[stone road turkey calls]

What do mean half way through the glueing stage

[MarkJM]

What do mean half way through the glueing stage

I let my calls sit for about 10-12hours. at about 3 or 4hours it'll crack

[ttcustomcalls]

how tight is the lip of the call around the surface?

[lightsoutcalls]

how tight is the lip of the call around the surface?

From original post:

Also I am making the rim a little bigger than my surface so it has plenty of play

[stone road turkey calls]

are you clamping the crystal or useing a weight, could be to much clamp pressure. try a soup can or nothing at all.

[handcannon]

You might have a slight high point in the ledge. If you can put the glass in dry and work your fingers around the diameter of it trying to see if it wobbles then you will see if that is the problem. If it is the case, you will probably have two high spots on opposite sides of the call that the glass contacts with and not the rest of the lip. I had that happen a couple months ago and had to build a little sanding spool to fit in my drill thanks to a comment that Wendell made. (It worked too by the way. Thanks Wendell.) Those high points will make it crack when clamped or will at least not give you a good even gluing.

[Longbeardfever4ever]

I had my glass crack in a call the other day... The glass had enough room to fall out, but it was pushed to one side of the call farther than the other and cracked closer to that side...

[WillowRidgeCalls]

Try putting an alum surface in it and clamp it tight right after you tun it. Let it sit for a day, then put your finish on it. If you put your finish on it right after you turn and sand it, you maybe sealing in the problem, let that pot cool 24hr before you put finish on it. The same goes with your finish, if it is not completely dry it will move some as it dries. If your buffing your pots after you finish them, the heat created will make the pot move a bit, give it time to cool down.

[MarkJM]

Thanks guys, also willow, in this case I am not putting the finish on the call until it is glued together. The call has been sitting 24hr before I clamped it. I test the tightness of the surface by putting the surface in and turning the call upside down, if it falls out on its own, then I know its good. Wendell, I too make my rims just a bit bigger to allow for plently of play. In these particular cases, I think I had to much clamping pressure on the call. I was using 3 small clamps around the edge. I used to do a soup can, I will try that and see how it works out

[misfire]

What kiind of wood is it Mark? Most of the crystal surfaces I have had break were in splated maple. Also, how dry is the wood? Personally, I finish my calls inside and out before putting the glass in. This helps seal the wood and prevent a lot of moisture from permeating the wood and causing swelling

[pappy]

Mark, one question...are you clamping the glass beyond the leading edge of the pot? Are you applying pressure to the glass itself, away from the ledge of the pot? You may be putting too much pressure on the glass itself, I would do this, use a piece of aluminum as Scott says over the glass, make sure it cover the glass entirely, all the way to the edge of the pot, then .... put your weight on it, making sure it reaches the outer edges of the aluminum and not  directly on it. when I first started I would clamp my glass using those plastic spring loaded ones and put them on the glass past the leading edge, naturally they cracked because I was applying too much pressure to the glass it self away from the ledge.

[MarkJM]

The wood I was using was red oak drying in my attic for about 40 years. So dont put my clamps toward the middle of the glass? instead get a piece of aluminum and clamp the outter edge near the gluing edge? I will give this a try. thanks all

[Longbeardfever4ever]

I clamped a glass surface call once. It cracked. All I ever use now is a 12 ounce plus can of soup or something. Some folks don't even do that. Let it sit for 24 hours.