Softening plastic binding

[griff]

I have a mandolin whose tailpiece has pulled and twisted the binding under it away from the body. The binding is very stiff from age, and trying to return it to its place with just pressure would likely break it. What's a good way to make it pliable enough to clamp it into place. I'm sure either heat or acetone used sparingly would affect it, but which one is best and what's the dosage?

[FRANK]

practice you have the formula time and practice on a different piece best i can do

[Len Biglin]

Hi Griff , just shime a 100w desk lamp at the area to warm it up , the binding will soften , then glue it and tape in place and leave the lamp on it till the glue hardens, I recommend epoxy glue. Len

[Ned Knepp]

Griff
I've used a blow drier to heat the plastic but, in a case something like this, I also used a cauld and clamped the area back into place gradually while heating it then used the cauld to hold it in place when I glued it up. I usually depended on either Duco cement or hot hide glue. I think I might not try the epoxy because it may effect the top/side joint and that would be a real surprise for the next repairman. I guess the decision would depend on the circumstances.

I think a light bulb would work for heat as long as you are careful with the finish. I don't know about leaving it until the glue dries. I don't really know what benefit this would bring ( not that it's not possible that it would, I just can't see any) and I worry about the finish when ever I apply a lot of heat to an area and don't like leaving it on longer than I need to.

It seems to me that there must be an underlying issue with the tailpiece that it would pull up the binding. I don't think your tailpiece should be able to rotate enough to do this. Has that been addressed?

Ned

[Ron Frazier]

don't and I say DONT heat it to much as the plastic is more than likely celoid and heating to much it will act like a dynamite fuse. Try some of your guitar picks and see how much heat it takes before it goes.

Ron

[Ned Knepp]

I don't know, Ron, picks don't seem to be as much fun as they used to be. Last time I tried to light one it just smoked. I was SOOO let down. I agree about the plastic binding and heat though. Better safe than sorry.

Ned

[Len Biglin]

Hi again , Just to clear things up a bit , My method above uses the desk lamp to warm the plastic binding and this expands it so it fits as it used to, you then glue it in place and leave the lamp on so it wont shrink . When the glue is hard you remove the lamp and tape and clean up as req'd . I used epoxy because it is very strong and cleans up well while liquid. I have not tried this on celuloid , and I'm not aware of it's combustible properties.I think celuloid is the stuff that smells like camphor when sanded or scraped ? is that right Ron? Len