flexible adhesive

[Ian Radin]

I am building smallish wall cabinet. Top is arched , made up of 7 a bit over 1/8 in. thick walnut epoxied together i.e. about an inch thick and 12 in. deep. Bottom is solid as are sides. Top and bottom are female dovetailed to take male dovetailed sides. I plan on gluing sides to top and bottom only at front to allow sides to probably shrink (I am in south Fl. and it will go to the land of central heating). Even though it is dovetailed , I hate to leave the rear unsecured. What came to mind is a bit of 3M 5200. Any better thoughts, objections? Thanks.

[Kevin Jenness]

I am guessing that you are talking about sliding dovetails. Why do you think the top and/or bottom will move at a different rate than the sides? Is there a crossgrain issue, i.e. different grain directions in the pieces? If so, just make sure the joint is tight enough to hold together without glue, and glue only the front few inches. If not, glue the length of the joint. Be aware that you have to work quickly with water based glue on a tight fitting joint that long. I would stay away from 5200, it can make a real mess fast.

[Stephen Cherry]

What came to mind is a bit of 3M 5200. Any better thoughts, objections? Thanks.

It seems to me, if anything would work, 5200 would. I consider it to be one of the wonders of modern chemistry.

[Joe Angrisani]

I am guessing that you are talking about sliding dovetails. Why do you think the top and/or bottom will move at a different rate than the sides? Is there a crossgrain issue, i.e. different grain directions in the pieces? If so, just make sure the joint is tight enough to hold together without glue, and glue only the front few inches. If not, glue the length of the joint. Be aware that you have to work quickly with water based glue on a tight fitting joint that long. I would stay away from 5200, it can make a real mess fast.

I'm with Kevin on thinking the grain directions are in line. Even though the top is laminated, it sounds like things are going to move together. Can you elaborate on the layout, specifically regarding grain direction?

[Ian Radin]

Kevin and Joe; Yes, they are sliding dovetails and the grain does run up the sides and across the top and bottom i.e. simpatico . Generally I use conventional dovetails in this sort of work, but the arched top (with overhang) would make for a bit of work. However my main concern is that the top, being laminated, (with WEST epoxy (Stephen, this stuff gets my vote)) will not move very much. Somehow I just cannot see those six layers of epoxy yielding. By the by I do cover the front and ends of the top with generous 1/16 in. veneer to hide the laminations (covering up the crime). As much as I would like to glue it up solid, I am afraid of the top not shrinking with the sides, resulting in a situation too horrible to contemplate. On the other hand, I hate to leave most of the sliding dovetail unglued (though I am not exactly sure why). So I am back to my compromise position of the either loved or hated 5200. What say you. Ian

[Kevin Jenness]

The epoxy layers will slow but not eliminate the absorption and loss of atmospheric humidity. I would no hesitate to glue the length of the joints, but if you're not confident with that, a tight fitting French dovetail partially glued should keep the parts attached indefinitely.