Edge joining

[borislp]

Every time when I have to glue up boards edge to edge I reinvent different way of clamping. Do I have to reinvent the wheel? Is there around more or less preferred way of doing this? Sorry if this question too naive and stupid.
P.S. Last time ( yesterday) I introduced a new element to my clamping -- in order to prevent warping I clamped a board across the panel, i.e. I clamped the board to the workbench from 2 opposite sides ofthe table, while my glue up was under the board thus I prevented warping. Of course in addition I clamped thge panel edge to edge with 3 clamps. Does anybody use this "trick" with the board across the glue up, or this is complete nonsense?
Boris P.

[Scafmaster]

I have done a couple edge joints and that is the way I found to be easiest. You could probably make some kind of jig to fit on your table to make the clamping quicker, if you are going to be doing alot of it.

[LanceM]

If you have a good edge on all of your boards and the boards are flat you shouldn't be getting warping by gluing them together. I think that you may be using too much clamping pressure. Just enough pressure to close the joint and get some glue squeeze out is enough, no great feats of strenth required :) Depending upon the lenth of the boards I usually use 2 clamps on the bottom, one on top to help equal out the clamping force on the boards, more clamps for greater lenghts.

Lance

[borislp]

>If you have a good edge on all of your boards and the boards
>are flat you shouldn't be getting warping by gluing them
>together. I think that you may be using too much clamping
>pressure. Just enough pressure to close the joint and get
>some glue squeeze out is enough, no great feats of strenth
>required :) Depending upon the lenth of the boards I usually
>use 2 clamps on the bottom, one on top to help equal out the
>clamping force on the boards, more clamps for greater
>lenghts.
>
>Lance

No, they seemed to be flat -- probably the reason was that the clamps were not aligned very good. BTW, what type of clamps is better to use for this purpose?

[Cody Colston]

I'm no expert at this, but for gluing up panels, I use 3/4" pipe clamps spaced about 8" apart (same as my biscuits) and alternate one underneath, one on top.

Just lightly snug the clamps, make sure the edges are even and then tighten until a small bead of glue squeezes out.

With 4-square stock, I've had no problems with the panels warping.

Cody

[ol]

The expert at anything was once a beginner...

[/ol]

[Sawduster]

I use cauls most often when clamping up wide panels. This is more to keep the joint from sliding around on the glue leaving one board higher than the other than to prevent warping. I also minimize this slide by applying glue to one surface, sticking the two boards together and rubbing them back and forth together to spread the glue out, take them apart then stick them back together. I have a tendency to apply a bit too much glue and the sliding is caused by that. By rubbing the two pieces together, I'm spreading the glue out and pushing some of the excess out of the joint. Some situations I will use a caul or three on top clamping those to the bench. Other times I will use cauls both on top and bottom. In either case i just snug up the clamps on the cauls so that they are applying only a tiny amount of pressure. Then I attach the clamps that will pull the joints closed, and tighten them just a bit past snug. Then tighten the caul clamps a bit more.

[Chuck in NC]

When I glue up panels I find it difficult to get the top and bottom surfaces to line up "perfectly". I end up with some joints perfect and others off maybe 1/32-1/64th. I end up using the ROS to level these up. I joint them to perfection and plane...dry fit shows they are very good but when I add glue and squeeze, the boards slide slightly up or down...joint lines themselves are hardly visible at all.

I know it's technique I just haven't solved it. I am very detail oriented so it drives me nuts. Tempted to get a wide sander but money gets in the way.

I suspect I'm applying too much pressure (ok, force) but it's hard to ease up if you aren't sure. I mean, who wants to end up with a visible glue joint line?

[borislp]

>I use cauls most often when clamping up wide panels. This
>is more to keep the joint from sliding around on the glue
>leaving one board higher than the other than to prevent
>warping. I also minimize this slide by applying glue to one
>surface, sticking the two boards together and rubbing them
>back and forth together to spread the glue out, take them
>apart then stick them back together. I have a tendency to
>apply a bit too much glue and the sliding is caused by that.
> By rubbing the two pieces together, I'm spreading the glue
>out and pushing some of the excess out of the joint. Some
>situations I will use a caul or three on top clamping those
>to the bench. Other times I will use cauls both on top and
>bottom. In either case i just snug up the clamps on the
>cauls so that they are applying only a tiny amount of
>pressure. Then I attach the clamps that will pull the
>joints closed, and tighten them just a bit past snug. Then
>tighten the caul clamps a bit more.

Yea, by warping I meant boards sliding relative to other in vertical dimension.
Stupid question: what is caul?

[Sawduster]

Cauls are them boards you mentioned running perpendicular to the joint. Use C-Clamps generally to clamp them either to each other, or to the bench.

[mstens]

I'll second the cauls. They'll solve this problem.