Lamination Woes

[Mike OMelia]

Whenever I do laminations to build up stock for legs, e.g., I start with well finished wood, and titebond. Dry fit is excellent. Glue application is good and even. But as soon as I clamp anything, dreaded movement occurs. Yes, locator pins of dowels would stop this. What is your technique to eliminate movement?

Mike

[Mike Henderson]

I don't have that much trouble with movement during clamping. If your problem is slippage side-to-side, clamp some scrap on the outside of the work, as cauls, before you do the clamping. Put waxed paper between the "cauls" and the work. If your problem is slipping lengthwise, use a long clamp and clamp the work lengthwise before you do the clamping.

But in any case, if you're careful to put your clamps "square" to the work before clamping, you won't get that movement. The movement is caused by the clamps trying to get square to the work - they will move the pieces of the work to get square. And glue is a good lubricant.

Mike

[Putting dowels, biscuits or dominoes in stock for legs that are to be turned is never a good idea. It's too easy to make a mistake and wind up turning into the dowel, biscuit or domino, thus ruining a piece you put a lot of work into.]

[Bryan Cowing]

I put two clamps to pinch and edge first, then add more clamps to the project. Then reposition the two clamps you have at the edge to a more suitable location.

[Rick Fisher]

I have gotten frustrated an shot 23 ga pins into thicker veneers on table legs.. A week later, I have no idea where they are. Later, I can router or sand through them with no problem ..

On table legs, If I am going to use a 1/4 Radius eased edge, I usually make the veneer 3/16 or even 1/4" .. the seam dissapears better if it lands in the radius of the ease over.

[ken gibbs]

Rick,

You must go through a lot of router bits if you rout through pins.

[John Tallyn]

I usually make my laminated legs an inch or two longer than I need, and put my dowels at each end. When everything is nice and dry, I cut off the extra inch at each end. I usually place a handscrew clamp in the middle across the glueing.

[Mike OMelia]

I usually make my laminated legs an inch or two longer than I need, and put my dowels at each end. When everything is nice and dry, I cut off the extra inch at each end. I usually place a handscrew clamp in the middle across the glueing.

I like this idea the best! Thanks

[Rod Sheridan]

I'm must be missing something because when I glue up blanks they're oversized.

Yes the glue is a great lubricant, and I'm often out by 1/8", hover they're going to get machined to size after the glue dries.

regards, Rod.

[Mike OMelia]

Right. But with some wood and its cost, I would like to minimize that. I guess I'm cheap! :)

Mike

[Frank Drew]

I don't like to laminate legs, but for laminations in general I've sometimes driven a couple of small brads well into the center of a face to be glued (no danger of being exposed by subsequent machining), cutting the brads off so that just a tiny bit is still exposed (like a sixteenth), but that small bit will bite into the mating face and prevent slippage, without preventing the laminations from coming together nicely.

[Jerome Hanby]

I like this idea the best! Thanks

Ditto, that is a good idea. Consider it stolen!

[Mike OMelia]

Ditto, that is a good idea. Consider it stolen!

Yup. I dont like to introduce any metal since there is always a risk of finding it. But I would like to find some thin hardwood dowels, like maybe 1/8"? My new Trend M&T jig does dowels.

Mike

[John Tallyn]

Lee Valley sells 1/8" birch dowel rods.

[Mike OMelia]

Thanks for the dowel source.

BTW, Its not just that the end product is slightly off... its just the whole process of trying to get the glue to tack up and hold without slipping. Locator pins will make the process quicker and more efficient.

Mike

[Howard Acheson]

Here are a couple of old time tricks used by many woodworkers.

The easiest thing to do is to drive in a wire brad about 1/4" and then nip it off with a pliers cutter. This will create a raised point about a 1/32" above the surface. When you put another piece of wood on top, the nib will go into the other piece slightly and prevent the pieces from moving as you apply clamp pressure. All you need is two brads to completely immobilize the pieces. Put them where you won't run into them with your tooling.

Another trick is to sprinkle a few grains of sand on top of the surface that you have applied the glue to. As you apply clamp pressure the granules will dig into the two surfaces and prevent the two from wiggling around as you apply clamping pressure.

[Chip Lindley]

Yup. I dont like to introduce any metal since there is always a risk of finding it...

Mike

Elaborating on the hidden brad fix, one can use brass escutcheon pins with the heads clipped off and not worry later, should some cutter slice through. For thick legs, the brass brads will never be touched.

[Mike OMelia]

Are you saying a jointer or a planer will not experience blade nicks if they come into contact with those pins?