Panel Clamps - Do they make sense?

[Allan Speers]

I'm about to start a long, involved project, which will include a number of cabinets & solid doors.

I've never been too vexed by large glue-ups, but then I haven't done many, either. I'm trying to decide if I should get some kind of panel clamp. Either 2 of these:

http://www.rockler.com/damstom-38-in-panel-clamp

Or maybe those "bowed wood" things a lot of guys make themselves. (I forget the name.) Both dinguses are obviously time & frustration savers, except one thing bother me about this method:

When you cut your individual strips of stock, no matter how careful you are, they tend to move a little after you've finished milling them. (unless you live on a magical planet, far far away.) So, If you make your strips a little over-thick, and do your glue up "only from the sides," those little stresses stay relieved, and you then re-flatten the whole panel. I'm fond of hand planes, and am a hobbyist in no hurry, so this has never bothered me.

Now, If you use something like that Damston panel clamp, (above) It seems to me that you would me stressing the individual strips, forcing them back from whence they came. After your glue dries, isn' that just asking for trouble?

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Thoughts?

Alternate methodologies?

[Kent A Bathurst]

I'm about to start a long, involved project, which will include a number of cabinets & solid doors.

I've never been too vexed by large glue-ups, but then I haven't done many, either. I'm trying to decide if I should get some kind of panel clamp. Either 2 of these:

http://www.rockler.com/damstom-38-in-panel-clamp

Or maybe those "bowed wood" things a lot of guys make themselves. (I forget the name.) Both dinguses are obviously time & frustration savers, except one thing bother me about this method:

When you cut your individual strips of stock, no matter how careful you are, they tend to move a little after you've finished milling them. (unless you live on a magical planet, far far away.) So, If you make your strips a little over-thick, and do your glue up "only from the sides," those little stresses stay relieved, and you then re-flatten the whole panel. I'm fond of hand planes, and am a hobbyist in no hurry, so this has never bothered me.

Now, If you use something like that Damston panel clamp, (above) It seems to me that you would me stressing the individual strips, forcing them back from whence they came. After your glue dries, isn' that just asking for trouble?

-------------

Thoughts?

Alternate methodologies?

The bowed wood things are called cauls. They are excellent. I have never had any of the issues you are talking about - I don't think there is enough movement to worry about - plus, same species, is going to move the same - unless you have your micrometers in play.

By trial-and-error, I developed a system of cauls and clamps that works wonderfully - small panels all the way to a 44" x 84" dining table. My technique has gotten to the point where, after I pull the clamps and cauls, I run a task-assigned hand scraper to remove the rubbery glue squeeze out. Then, I go back with a good scraper to level the glue joint. That is all it takes. Those boards are dead-nuts aligned. AIn't never grabbed no handplane [and I got a bunch to choose from, if I wanted to]. THis is not magic, it was repetition, concentration on the details, and focus.

I honestly think you are imagining monsters under the bed, Allan. While some may be there, they aren't of this flavor.

Also - on my cauls, I set them up as close together as I can, determined by the interspersed pipe clamps which pull the joints together - caul set - pipe clamp - caul set - pipe clamp. I can get the cauls to about 7"-8" aparts, and still have room to turn the pipe clamp handles. [Your photo show 2 on the ends. That is not enough by a loooooong shot.]

And - the pipe clamps alternate - one on the top, then one from underneath.

The cauls are made from 8/4 HM, with packing tape on the business surface, and 1/2" x 3/8" crossing grooves to sit over the glue joint - the squeeze out doesn't get smeared into the wood that way.

And - I have some bracket/stand thingies that the bottom cauls sit in - gets them the correct height off the table for he C-clamps that pinch them together.

[Mike Henderson]

Wood will do what wood will do, no matter how you clamp it. But you can make a few cauls for about $5 instead of buying those clamps. See here.

Cauls are good for getting the boards to line up as you put pressure on your clamps. After you take the panel out of clamps it will go the way it wants to go. That's why stock preparation is so important.

Mike

[Allan Speers]

Good to know, Kent. I think I'll make some cauls myself, as I have a lot of HM out back.

I like that idea of grooves for squeeze out, but how does that work with the packing tape over it? Any pics?

I assume you're cutting them with a 2" SQUARE profile, yes? - So then which grain-orientation is best for the cauls? Surely, one way is stiffer than the other, but too stiff is no good, either. What is working for you?

Last: When laying out your strips, do you make sure to alternate grain direction, as some folks suggest, or does that also not really matter much?

[Kent A Bathurst]

Good to know, Kent. I think I'll make some cauls myself, as I have a lot of HM out back.

I like that idea of grooves for squeeze out, but how does that work with the packing tape over it? Any pics?

I assume you're cutting them with a 2" SQUARE profile, yes? - So then which grain-orientation is best for the cauls? Surely, one way is stiffer than the other, but too stiff is no good, either. What is working for you?

Last: When laying out your strips, do you make sure to alternate grain direction, as some folks suggest, or does that also not really matter much?

ALso - you should take the time to look at the link MIke H included in his note. He did a bang-up job with BORG framing lumber. I was way gone around the mountain before I saw that - I went for the HM because I was royally ticked and frustrated with clamping and cauls and was bound and determined to put "paid" to that noise. WHich I did. But 8/4 HM ain't cheap, and is likely overkill.

Having said all that.............

Will post photos soon - tomorrow, hopefully.

I put the packing tape on, and then a couple months later realized the value of the grooves - just drug them across the TS. THe glue doesn't get up in there, so I'm not worried. In fact, I have advanced to a level where the packing tape never comes into play, but it is a good safety measure, and I would do it again.

Yeah - square profile - roughly 2". Get a slab of 8/4 and cut it for best yield. THere is no grain orientation issue. That stuff is stiff either way. And - the precise grain orientation likely varies from board-to-board, right? Depending on where in the log it came from, and how it went through the saw mill. Forget that issue entirely.

There is a lot of what I regard as hokus snake-oil about grain orientation and direction and cupping and what-have-you. Pretty much all nonsense to me [not picking a fight with anyone of a different belief system, guys.....back away from the keyboard].

I sequence the boards and orient them to get the "most pleasing" visual grain orientation. I often pay for bookmatched boards....so you can easily figger out how they go together. In any other case, I just try to get the grain aligned so it looks good - not stupid. Move them to different spots in the glue up, try both sides, flipping them back and forth...........The best presentation is not always easy - comes down to a judgement call - but the dumbest is readily apparent.

[Tom Morassini]

I use angle iron wrapped with packing tape for my cauls (thicker steel, not aluminum). Sure you won't get the added pressure in the middle of the panel that you'll get with convexed cauls, but for cutting boards and door panels they work great for me. You could always put some playing cards or whatever for spacers in the middle to add a little pressure in the middle. I haven't tried them on a large table or anything that big yet.

[Michael Stein]

ALso - you should take the time to look at the link MIke H included in his note. He did a bang-up job with BORG framing lumber. I was way gone around the mountain before I saw that - I went for the HM because I was royally ticked and frustrated with clamping and cauls and was bound and determined to put "paid" to that noise. WHich I did. But 8/4 HM ain't cheap, and is likely overkill.

Having said all that.............

Will post photos soon - tomorrow, hopefully.

I put the packing tape on, and then a couple months later realized the value of the grooves - just drug them across the TS. THe glue doesn't get up in there, so I'm not worried. In fact, I have advanced to a level where the packing tape never comes into play, but it is a good safety measure, and I would do it again.

Yeah - square profile - roughly 2". Get a slab of 8/4 and cut it for best yield. THere is no grain orientation issue. That stuff is stiff either way. And - the precise grain orientation likely varies from board-to-board, right? Depending on where in the log it came from, and how it went through the saw mill. Forget that issue entirely.

There is a lot of what I regard as hokus snake-oil about grain orientation and direction and cupping and what-have-you. Pretty much all nonsense to me [not picking a fight with anyone of a different belief system, guys.....back away from the keyboard].

I sequence the boards and orient them to get the "most pleasing" visual grain orientation. I often pay for bookmatched boards....so you can easily figger out how they go together. In any other case, I just try to get the grain aligned so it looks good - not stupid. Move them to different spots in the glue up, try both sides, flipping them back and forth...........The best presentation is not always easy - comes down to a judgement call - but the dumbest is readily apparent.

I have to ask. I have tried to figure it out, but what does BORG stand for??

[scott vroom]

I have to ask. I have tried to figure it out, but what does BORG stand for??

BORG refers to either of the 2 infamous big box stores Home Depot and Lowes. Borg is also the name of the inhabitants of a futuristic cube shaped space ship whose only purpose is to assimilate all cultures it encounters. I guess some folks along the way drew a parallel between the Orange Big Box Home Depot, the Blue Big Box Lowes, and the space peoples? I dunno.

[Britt Lifsey]

I have to ask. I have tried to figure it out, but what does BORG stand for??

I've heard both Big ORanGe store which leaves out any blue ones and Big Old Retail Giant.

[Sam Murdoch]

There is a lot of what I regard as hokus snake-oil about grain orientation and direction and cupping and what-have-you. Pretty much all nonsense to me [not picking a fight with anyone of a different belief system, guys.....back away from the keyboard].

I sequence the boards and orient them to get the "most pleasing" visual grain orientation. I often pay for bookmatched boards....so you can easily figger out how they go together. In any other case, I just try to get the grain aligned so it looks good - not stupid. Move them to different spots in the glue up, try both sides, flipping them back and forth...........The best presentation is not always easy - comes down to a judgement call - but the dumbest is readily apparent.

No fight here - I completely agree. Technique/method goes a loooong way to alleviate issues. I go for the best look at the outset. Never been bit by that preference.

[ken masoumi]

I use angle iron wrapped with packing tape for my cauls (thicker steel, not aluminum). Sure you won't get the added pressure in the middle of the panel that you'll get with convexed cauls, but for cutting boards and door panels they work great for me. You could always put some playing cards or whatever for spacers in the middle to add a little pressure in the middle. I haven't tried them on a large table or anything that big yet.

That's what I use for small boards,works very well but for wider boards I use a combination of wooden cauls & angle irons.

[Pat Barry]

I went for the HM because I was royally ticked and frustrated with clamping and cauls and was bound and determined to put "paid" to that noise. WHich I did. But 8/4 HM ain't cheap, and is likely overkill..

What is HM? Hard Maple?

[Michael Stein]

Big Old Retail Giant.

I like that one, makes sense now...

Thanks yall! Sorry for the hijack on my first post

[Kent A Bathurst]

What is HM? Hard Maple?

Yep



1010101010

[Mike Schuch]

When I glue up panels I always use dowels. Not so much for strength but for alignment. I have an old Davis and Wells horizontal boring machine which makes well aligned dowel holes quick and easy. Of course with door panels I have to think ahead enough to not put a dowel too close to an edge that will be milled with a panel raising bit... BUT you only make that mistake once!

If I do a good job of jointing nice straight boards clamping pressure is minimal... as it should be. With minimal clamping pressure I have not had any problems with the entire panel bowing.

I actually have 3 and a half of these clamps that I have never purchased pipes for (they use 1/2" pipes instead of the usual 3/4" of the rest of my pipe clamps use.) I got all 3.5 of them off Craigslist for $20 and couldn't pass them up. Someday I look forwards to seeing how well they work on panel glue ups without using dowels.
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http://www.leevalley.com/us/wood/pag...73&cat=1,43838