laminating thin pieces of hardwood to MDF

[Zach England]

I am doing some speaker cabinets out of MDF and on the front baffle I want to do a herringbone patters with sapele strips. I was planning on re-sawing the 13/16 sapele to make better use of the wood, so I will be left pieces about 3/8 thick by 2-3 inches wide. What is the best way to adhere these to the mdf? I do have a pin nailer, but I'd rather not use it because I'd like to plane the front flat. I'd also like to avoid contact cement because it is so unforgiving and I might need to fudge the placement of the strips a bit to get them to fit together. I also could clamp each one in place, but this is going to get difficult when I am in the middle of the cabinet. Ideas?

Thanks.

[Gerry Grzadzinski]

Make them thinner, about 1/8". If they're too thick, you may have problems with movement. I'd glue them together into a veneer sheet, using CA glue. Put some wax paper on a table and glue them up on that. Once you have the "sheet", apply it like regular veneer, preferably with a vacuum press.

[Jamie Buxton]

I'd use yellow glue, and devise some way to get clamping pressure in the middle of the panel. For instance, you might could drive screws into the sapele from the back of the MDF. I'd glue up the panel, and trim to fit afterwards.

You are likely to have a little issue with expansion or contraction of the sapele, but not too much. You'll be making a panel that looks like herringbone flooring. There may be small gaps between the pieces of sapele, but the fact that the pieces are at right angles to their neighbors reduces the visibility of the gaps.

[Zach England]

Make them thinner, about 1/8". If they're too thick, you may have problems with movement. I'd glue them together into a veneer sheet, using CA glue. Put some wax paper on a table and glue them up on that. Once you have the "sheet", apply it like regular veneer, preferably with a vacuum press.

Why thinner? I'd think if they are thicker they will be less likely to shrink.

I am interested in this "sheet" method, but have never heard of it. Do I attach a "backing" to it as I glue it up?

[Russ Filtz]

Not sure, but maybe the thicker section will have more "power" in movement and do something nasty to the MDF?

I know MDF has some good qualities for speakers, but I just don't trust it. I'd use outdoor quality MDF if i had to use it or maybe some Baltic Birch (more plys = less resonance?). One small separation or failure in the seams or lamination, add water, and poof! The MDF swells up. Of course, you shouldn't have moisture near your speakers, but still.

[Joe Chritz]

Why thinner? I'd think if they are thicker they will be less likely to shrink.

I am interested in this "sheet" method, but have never heard of it. Do I attach a "backing" to it as I glue it up?

One would think that is the case but it really isn't. Generally shop sawn veneer is kept at 1/8" or less to remove any problems from movement.

The MDF is your backer. A vacuum press would be ideal and some very careful lay out and tape.

Maybe you could piece them together in smaller sections on 1/4" MDF, clamp with cauls and then put the smaller pieces together onto the final sheet.

Ultimately all it needs is glue under the veneer and pressure until it cures. Getting that is often the difficult part.

Joe

[glenn bradley]

+1 on thinner. I have had thicker "glue-ons" split but have yet to have a failure with 1/8" and thinner. Just my limited experience.

[Gerry Grzadzinski]

Why thinner? I'd think if they are thicker they will be less likely to shrink.

I am interested in this "sheet" method, but have never heard of it. Do I attach a "backing" to it as I glue it up?

The thicker they are, the more force they'll exert when humidity changes.

I wouldn't use a backing. If the size is unmanageable, make it in two (or more) sections and veneer tape it together. If you use perforated veneer tape, you can even tape the glue side with a few pieces and leave it under the glue.

[Eric Kipker]

Have been working on a end table project with some left over mahogany from an entertainment center I built in 05. I re-sawed the mahogany (I paid $10.00 bf.ft.back then) into about .100" thick veneer and ran it through my drum sander doen to about .040. I coated the veneer and the substrate (3/4" birch plywood) with a rolled on thickness of yellow wood glue, as recommended by my local Woodcraft Store here in GR and allowed both to dry completely then using an old clothing iron bonded the two together. Read about this on Joe Woodworker and here on this forum. I cannot guarantee anything as I have not completed it yet but so far so good. Still to be determined any issues with the shrinking.