Bent lamination question

[FrankAtl]

You may have already answered this and I overlooked it, but what type of glue are you using?

[Steve N]

I have only done a few bent lam pieces, the first form I made was approximately the same height as the pieces I was forming. I had that slip and slide movement. On the next one I'd either heard, or read to make the form a bit taller than the pieces. I didn't see a down side because my clamps would still go over the taller form. No slipping at all, with only making the form taller. I cannot begin to understand the forces at work there, just that it did work.

[johndi]

Thanks for all of the replies. The people on this forum are awesome.
The second try came out much better with the tape cuffs and C clamps. Did get a little twist at one end, but I do make the glue ups longer than needed so it shouldn't be a problem. The first glue up, not so much. By the time I jointed the sides parallel it was too narrow to use in the piece. It will make a nice piece for practicing cutting the tenons, setting up the router to cut beads on the edges, and for staining.

I used title bond original on the first glue up, but with the heat it set up too fast as I was running around with clamps trying to level the darn thing.
The second one I used titebond III and it allowed me to not resemble an old I love Lucy skit while clamping it up.

The ratcheting strap idea sounds like a good one. I'm going to try it on the dry glue up on #3 today just for giggles. If I'm comfortable with it I might give it a go .

Again, thanks for all of the great replies.

[FrankAtl]

You might want to try plastic resin glue. It sets up much slower and gives you time to get everything in position.

[handi]

Plastic resin glue is awesome, but I generally use titebond since I never have plastic resin glue when I need it. NEVER had an issue with creep. 

EVERY glue up will spring back some when released from the clamps, so over bend slightly in the clamps. 

I also generally use two-sided forms for clamping. Lay out both inner and outer radii (the thickness of the bent part) and cut out the waste, then sand to the lines. Do it right and you will get a gap-free part using just a few Clamps. I typically buy 2x8s or 12s for making the forms.

[mike4244]

I make the laminations about 2 " longer and 1/8" wider than the finished piece. I use hot hide glue and coat two opposing sides and let it cool. Takes 5 minutes or so before it is cool. I then drill a pilot hole thru the two pieces and screw it to the form. I heat the laminations with a heat gun as I clamp the lamination to the form. At the far end I drill and screw the lamination. I repeat this with on strip at a time. The clamps can be removed after the lamination cools, again 5 minutes or so. To remove the lamination from the form I band saw the piece to length. The excess on the form is unscrewed a piece at a time. After the laminations are glued up I usually wait 2 hours before machining to thickness and length. By applying the glue and clamping dry it is easy to get the laminations even. Then heating with a heat gun activates the glue. I worked with one man that shot brad nails into the laminations where it would not show thru. He only needed a few clamps. I never tried it myself as I had no problems with my method.
mike

[R Clark]

I have made a couple of Hal Taylor-plan rockers; the rockers are a 9-layer lamination done in one glue-up (per side).  They key to success is the gluing form, along with bracing structures on one side and clamps on the other side to eliminate side-to side movement.

Length and width on the final glue-up are fine-tuned on the table saw.

[handi]

Because it is available now, episode three of my TV show, Woodcademy TV is a Library Stand build that uses three different bent wood laminations. This episode discusses ripping the strips, making the forms, over-bending, and jointing/planing the finished laminations. You might find it useful.

It is free to watch with your Amazon Prime account, and if you do not have a Prime account, you can still watch it for free but Amazon will throw in a couple ads.

[FloridaRetiree]

You might want to try plastic resin glue. It sets up much slower and gives you time to get everything in position.

BINGO!

Have always used a thermosetting glue when building stack laminations.