Pocket Hole Joinery with Melamine Cabinets

A cabinetmaker tries pocket screws for assembling melamine cabinet carcases, and discovers that it doesn't work. July 21, 2006

I run a small shop and generally shy away for work that involves melamine particle board but occasionally I'll take the odd job. I have to date dowelled cabinet carcassas together with no issues its fast error free and simple to assemble on site. I decided on this current custom closet that I would use the K3 and pocket hole everything together to see if it could be a better faster way.

Needless to say I'm going mad with alignment issues when screwing the joint together. I purchased an extra right angle clamp (RAC) and even with two of these at as high a pressure as I can manage the panels will shift about 1 mm. Not much but too much for melamine carcassas.

I have solved the flush joint issues by counter sinking the exit hole. I do this with a flashlight in the hole so that I can spot the area. The counter sink provides the needed space for the expanding fibers of the PB caused by the screw entry but does not solve the movement of the panels during screwing.

Forum Responses
(Cabinetmaking Forum)
From contributor B:
I haven't done anything with melamine in years, and always used the MDF core stuff. I used pocket screws combined with biscuits. Melamine to melamine kept the glue from working, but the biscuits gave me at least a little holding power from glue. Biscuits also kept the slipping down.

From contributor F:
Even with the Castle machine I also get slippage with Melamine. I pin nail the cabinets together, and then screw them. With your machine you’re going to get more slippage, much less with a Castle or any low angle set up. Plywood parts do tend to work better, a tap of the hammer and there right on, with Melamine stuff starts to blow out. I don't care for Melamine myself, but the tract homes I'm doing now require it. You could try offsetting the joint 1 mm, and let it slip into position - easier said than done.

From contributor M:

" I have to date dowelled cabinet carcassas together with no issues its fast error free and simple to assemble on site." Why aren't you doweling? Particleboard was made for dowels. You're going backwards on this. It's like using your chisel to cut dados when you have a tablesaw or router. Go back and drill for dowels and get it done. Use pocket holes for lumber, MDF, and plywood.

From contributor C:
Confirmat screws are your best solution for melamine cabinets.

From the original questioner:
I figured that would be the consensus. Well, I’m always looking for a better faster way and this wasn't it for melamine pb panels - dowels it is.

From contributor F:
Kreg makes a hole clamp for this purpose. If you still want to use pocket screws, you might want to get a couple of the clamps.

From the original questioner:
I have the RAC, two of them. Being the stubborn kind of person that I am, I thought I would give it one last try, using the Woodpeckers assembly braces. Even with two of these, it simply was not acceptable. I got to pretty close but if I want to get paid that’s just not enough. Not to mention all the extra time fussing with clamps and such. As mentioned previously I'm dowelling and getting it done.