3/4" Melamine...........new problem for me.

[Rick Potter]

OK, I have seen undersized ply, recently undersized MDF and Baltic Birch, etc., but recently I picked up 10 sheets of two sided Melamine from my hardwood supplier. These will be a starter kit for the four large walk in closets and pantry at our home. I got out my brand new 3/4" down shear router bit and cut a practice dado. It was too small. This melamine is slightly thicker than 3/4".

I grabbed a scrap of the last batch of double sided melamine I bought a few months ago, and it fit perfectly. Nothing wrong with the bit, so I tried three or four old 3/4" bits and they also fit the older scrap, but not the new.

Melamine was the last thing I could count on being sized right, but I suppose it varies by manufacturer now. I guess I will just have to break out the jig and make two passes.

Grumpy again.


PS: The dado bit made perfectly clean passes, no chip out at all. It was just an inexpensive Woodline. I don't like to use expensive bits on PB.

[Leo Graywacz]

Nominal. I hate that definition. But all sheet goods are of nominal thickness now.

[Curt Harms]

That's why I like the dado jig that's just two pieces of straight wood tied together at each end. Set one piece on one edge of the intended dado and clamp it. Insert a shelf, butt the second piece against the shelf and clamp. Use with a 1/2" X 1/2" pattern bit run along the clamped pieces. It doesn't matter what thickness of the shelf (or whatever) is, it always fits. The limitation is that it won't do dados less than slightly wider than 1/2". The wood whisperer showed a similar jig that used a router bushing and straight or spiral bit. That would do < 1/2".

[Peter Kelly]

Mat-formed particleboard "3/4" sheets from the Canadian mills are typically pressed to 19mm. Once the melamine sheets are pressed on to the board, it usually comes out to 19.5mm. Tolerance from panel to panel from the same skid is usually ± 0.200 mm. You're really better off butt-joining with RTA fasteners or biscuits for closets.

Be careful, melamine pb edges can be razor sharp.