Gluing Tops

[Bmth Builder]

Hey how is possible to glue thin bookmatched tops together with enough force for a gapless line, but so that you dont bow them?

Is it easier to glue one side to the body then butt the other up against it and apply both downwards and sideways pressure at the same time? (I imagine tightening clamps in two dimensions may be a problem?)

or rip the body in two, and glue each side of the top to a body peice, get the centre line flat and then glue the two sides together?

Cheers

[WezV]

you dont need massive amounts of pressure to get a seamless line, you just need to prep it well.

its worth checking out jigs and techniques used by acoustic makers since they do it with thin plates all the time

[avdekan]

I would glue both halves of the top to each other, and after that glue the top to the body.

you should take care to prepare the gluing well. do it on a straight surface, and assuming you prepared the gluing surfaces so they are straight and match in angle (90 degrees), a light clamping force applied both downwards (to keep the top level) and towards the centerline should suffice.

another thing that I do is after the top is in one piece I clamp it to the body (or to any other straight surface) until I glue it to the body, so it doesn't warp.

and although it seems obvious to say, I'm gonna say it anyway: put nylon between the top and the bottom surface when gluing.

B

[dpm99]

I really like this guy's method. It's pretty simple, and you don't have to build a jig.

-Dave

[NotYou]

I clamp a board to the table on one side of the top and use a square board on the other (about 1.5"-2" usually). I lightly clamp the square one down, so it doesn't pop up later. I glue together the two pieces that are going to make the top then place them between those clamped down boards. I clamp those with three long clamps parallel to the glued pieces so it squeezes everything together. Make sure to hold down the pieces being glued with something(I use plastic quick clamps, because they don't press too hard and allow the boards to slide together).

That's pretty much it. I'm making it sound a lot more complicated than it really is. I might have a picture on my computer that will demonstrate better.

Edit:

I don't have a picture, but I'll get one tomorrow if I remember.

Edited May 4, 2009 by NotYou

[Metalhead28]

I don't know how thin you're talking, and there may be a more clever approach - but i do it like this.

I just clamp some straight wooden strips across the width of the pair, with some wax paper underneath. It keeps the boards aligned and flat while applying the sideways clamping pressure.

[Woodenspoke]

As WeezV said you don't want massive amounts of pressure. First you starve the glue joint of glue of you do and that is a bad thing. I have never been able to make a glue line invisible, except with paint. Even a book matched piece will show variations in grain which will bring your eye to the fine line separating the two sides. With grain that runs straight along the glue line like a spruce top on an acoustic it is easier to limit the visibility as your eye does not focus on the pattern changes. But it is still there if you look close enough. Of your joint stands out you are not making a big effort to get the edges perfect flat before gluing.

I think you are asking the impossible without using a single board. Book matching does not mean identical pieces.

[guitar_player]

I really like this guy's method. It's pretty simple, and you don't have to build a jig.

-Dave

That's what I do for acoustics just I use nails instead of sticks with clamps and I started using a strip of wood with packing tape on it down the center with a cement block on top instead of clamps. It's a very easy way to do it and I don't see why it wouldn't work for electric tops.