Glueing Up Tops

[Paul Vogt]

Does anyone have what they consider to be a great set-up for gluing up matched tops?

I do these one at at time, using bar clamps. I want to set up a system that would allow me

to glue up 5-10 sets in one evening, without using all those bar clamps. Any suggestions?

Thanks,

Paul

Charlotte, NC

[jaycee]

If you have enough table top space you could fix two lengths of say 3" x 2" and use folding wedges taped between the tops and the 3 x 2

[Woodenspoke]

When I glue up thin tops I never use clamps. Its the same method you would use to glue up an acoustic top. there are variations as well

You start wuth a pice of flat plywood with two strong cross pieces placed ontop at the top and bottom, spaced slightly wider than the top. Screw these pieces down. The spacing is determined by the width of the top the size of your wedges and if you add a loose bar to the top wedge to sit against the wood you are gluing I would make it over sized if you plan on using it for other guitars. You can alway add a spacer.

Using 4 or six wedges faced together in pairs you hammer the wedges tight against each other forcing the top together. Again you can add another piece of wood to sit against the side of the top. You will need some wax paper under the joint and some small clamps and a board across the top holding down the glue line . It does require plywood and time to construct. For 1/4" boards or thinner I only use this method. For thicker stock its a toss up. But it could work for both.

Similar glue up only using more clamps.

there is also the spanish method

http://www.luthiersforum.com/forum/viewtop...102&t=13053"

[Paul Vogt]

Thanks for the help. I use wedges in pairs when I clamp parts in my CNC machine, but I have not thought to use them for gluing. Do you think this gives adequate clamping force? I suppose it does.

An ideal setup for me would allow me to stack 4 or five sets in some kind of racking system that clamps

everything up, and manages the dripping glue somehow.

By the way, my tops are all 3/4 inch maple sets for carved top electric solid bodies. (Think PRS)

Thanks for all the suggestions, I'll post a photo of what I come up with.

By the way, I have two great fixtures that use fire hose with air stems installed for clamping. These work

great for gluing the tops to the tonewood, or for gluing up laminations in a 5 ply neck. They are easy to make as well.

I'm about to make another for gluing fretboards to necks. If anyone is interested, I'll post a picture or two.

Best Regards,

Paul,

Charlotte, NC

[erikbojerik]

I'd be interested to see the fire hose system.

[ihocky2]

We definitely need pictures of the fire hose clamp.

[Buter]

Should be something like this. Just over halfway down below the 'Platen Pressing' header.

B

[Paul Vogt]

Yes!

Very similar. Here is a picture.

I love this method. It's really fast, and applies very uniform and controllable force.

Best Regards,

Paul

[ovation22]

Saw

the other day showing how PRS does it. I thought it was interesting to see.

[Buter]

Great stuff to see, guys.

I've got a section of fire hose for just such a thing, but not a compressor big enough to use it yet. I've got a spray booth built and when I finally start using it, I'll have a compressor to run the hose press.

At the moment I use vacuum for most things - laminating necks, attaching fretboards and pressing tops onto bodies. The one drawback with vacuum is that you are limited to atmospheric pressure, approx 15 psi. During times of low pressure, you obviously have even less pressure to work with.

I don't use clamps too much for the actual building process anymore. Gluing up body blanks is about it, I guess.

I asked the small engineering shop I worked at when I was between careers to knock up a great top/body gluing jig/press for me. This thing would make gluing a top or body so quick and easy you'd get bored building guitars. Of course, the cost of turning my drawings into a single unit could buy you a guitar built personally by Mr. Smith himself quickly sent me back to more traditional ways!

Cheers

Buter

[Paul Vogt]

Buter,

The fire hose thing is really a nice solution. The hose comes from a local supplier that sells various rubber products and hoses (Catawba Rubber, Charlotte, NC) . Then I just go to the local tire shop, and ask for a high pressure stem, and install it in a simple hole in the hose. I clamp the ends with a strap of steel with a row of 10-32 machine screws (or similar). The fire hose I'm using is rated at 150 psi, so I'm not concerned with bursting the hose.

Another great thing is the clamping force you develop. My neck blanks are 39 inches by 2.5 inch. That's 97 square inches. Multiply that by 60 psi, and you get 5850 pounds of force. Better be sure your fixture is strong!

For laminating the tops, I have a similar fixture with about a 12 inch wide hose. I'll post a picture of the fixture. Drop in your parts, add air, done!

Your top glue fixture sounds very intriguing. Did you ever built one? It sounds like it's exactly what I'm trying to come up with.

Best Regards,

Paul

Charlotte, NC

[Woodenspoke]

I mean hose (new one to me) wedges or clamps it really is all the same.

I am not sure you want to attempt multiple tops in a single glue up I think you are asking for trouble. If one piece does not align more issues. Plus all that glue squeeze out will make a mess. If its open it can be cleaned off while it is still wet

You went to a lot of trouble to make that hose clamp. why dont you just set up a clamping station for the tops using pipe clamps cut to size. The whole thing can be on a cart or wall. Again a board with two clamps mounted underneath, in this case some electrical pipe hangers in a U shape to hlold the pipe. Add two cauls so you dont destroy the board edge and you have a single station using cheap pipe clamps. Mount them on a vertical cart and each station slides out like trays so you can glue and then put it back to dry. Saves space less work than wedges. Considering all the work you put into those air clamps this should be a cinch to build

I have seen this mounted on a wall in either a long continuous row

http://www.shopnotes.com/issues/062/extras/clamping-station/

Something like this only more refined and the clamps attached to a flat board or not.

http://www.woodworkingtips.com/etips/2007/06/22/sn/

[Paul Vogt]

Woodenspoke,

Thanks for the input. I'm pretty sure I'll end up with some kind of a station on a cart, that I can load wood into without fooling with individual bar clamps. I like the examples you provided, but I'm envisioning something more compact. Working in metal is not a problem for me, so I'll probably weld up some kind of a multi-level rack system. I might keep the cost down by using large bolts instead of clamp cranks. I sure appreciate the suggestions, and I'll be sure to post a picture of what I come up with.

Best Regards,

Paul

Charlotte, NC