Joining particle boards.

[PVR]

How do I join particle or MDB boards?

Peter.

[B A R R Y]

Glue and/or screws work well.

[<marierdj]

In order to give a proper answer we need to know what kind of joints you intend to make. Is it a butt joint, a scaft joint or a corner joint. Is your work structural, esthetical or functional.

[Mike]

Go over and sit down by them. ;-)

Sorry, it's getting late in the day...

[PVR]

I want to butt joint two grain printed boards, one 11.5" wide, one 8" wide and both 6' long. I'm thinking of using biscuits and water borne glue.

Peter.

[<marierdj]

You have a nice project. If this the end use of these two pieces is to be without any load or pressure, compression, twisting or extension your idea is suitable. The use of biscuits will not add any strength but will facilitate alignment of the two pieces. The use of pipe clams every 18 inches with moderate pressure should remain on overnight on a flat surface. That is one clamp under and one on top. Insert wood blocks between the clamp and the MDF to avoid pressure damages. This construction will be as strong as the weakest link. Conversely if you want a stronger construction your butt joint should be re-enforced with back up supports using hardwood stringers or salvaged hockey sticks running across the two pieces of MDF. These stingers should be glued and fastened in pre-drilled pilot holes with metal screws of appropriate length. You may want to countersink the pilot holes in the stringers for aesthetic purpose. Even if the MDF is not waterproof I would use an exterior wood glue like Lepage, Titebond or better.

[George]

You don't say how thick, but given the way MDF or other fine-grain particle boards swell and stay, I'd go dry biscuits for alignment, and something other than a water-based glue or sparingly.

Better would be the reverse glue joint type of router bits, though if the pattern is plastic imprint, you might want to check it on a scrap piece. Continuous spline is easily enough done, and you could make it a bit deeper than normal if the joint will be under any kind of stress.

[PVR]

Many thanks for your comments. The use of stringers may be possible because I am making two cabinets and the stringers could also function as shelf supports. It seems I have much experimentation to do before I start construction proper.

[Upscale]

You haven't said how thick the boards are that you're using, but if they're of sufficient width, you could use these connectors.

[PVR]

The boards are 5/8" and are grain printed. I take your point about using a non aqueous glue. I thought about using a spline but the grain print surface might be too delicate to go though my router. Some experiments are in order before I start construction.

Peter.

[George]

Use a slot cutter and either slick your router specially fine to avoid scratches, or doublestick the visible surface TIGHTLY to a piece of ply and pass the router over that. Or that past the table-mounted router, but I'd say your dimensions favor the former.

Make sure the doublestick doesn't lift the pattern.