Thread: Pocketholes in 16mm melamine?

Originally Posted by GraemeCook

I used 18 mm melamine rather than 16 mm for the cabinet carcasses in my workshop because the extra 2 mm makes them much more tolerant of errant driven screws.

Also advise against pocket holes; they are for real wood. I just used 65 mm chipboard screws, but pre drilled even though they are self tapping. No screws within 50 mm of a corner.

you could hang your cabinets in French cleats?

Pre-drilling is quite important in two situations. Where the cabinets will be subjected to heavier than usual use and when using long screws, >50mm. The ling screws allow you to pull the gable in real tight but it weakens the top and bottom that the screw is driven into. Particle board, though you can't see it, splits even with 50mm screws. That split can radiate out 25mm on each side. Even 15ga brad nails split particle board. PVA glue is a good idea as it is driven into the newly formed crack as you pull the gable in tight.

[QUOTE=DaveVman;2321844]

Originally Posted by The Spin Doctor

first off don't use those kreg system thingies.

Second and most important. What are you putting in the cabinets? Particle board, when standard construction methods are used, is pretty good for average kitchen loads but shop loads... How much weight you plan to load them up with will dictate material and method of construction.[/QUOTE

That is an excellent point. It would be tempting to put heavy things on top of them. Should I be using plywood instead?

From my perspective I would be using plywood. I've cheaped out, as I have an endless supply of melamine board available, but the cabinet don't stand up to the heavy loads like ply does. Even MDF is something I avoid now, humidity is a real enemy. Even when painted you'll eventually chip the paint off in a shop setting and it starts getting furry... Problem with ply is it's never flat.

Just screw it like everyone else does! use melamine adhesive if keen - will be far stronger than pocket holes!

Originally Posted by The Spin Doctor

Key is you glued them. The screws alone aren't good enough with board that crumbles like particle board does, 90% of the joint strength is in the glue.

Agree glue helps. Don’t know if it’s 90% though. Immediately after gluing the carcasses up I could pick the whole thing up and rotate it in the air without issue - lots of shearing forces and the only thing holding it together was pocket holes. Didn’t have the backing board on yet. Glue was still wet at that point. Not to mention the glue only has the same “crumbly” board to adhere to. If you’re careful when driving the screws then they hold well in my opinion.

I’m not arguing that melamine is the best material. But I’m happy with the strength of mine. Not to mention a bottle of melamine glue costs $30. If I had used plywood it would have been more than double the cost in materials and the ply would definitely not have been flat making everything harder.

DaveVman, not much harm in trying one out of 16mm melamine and see how it goes. A few unsolicited notes/tips:
- Sounds like you already have a pocket hole jig so all good there
- Make sure you use the course thread screws
- Use melamine glue (not normal wood glue) on all joints
- Do a test pocket hole on some scrap melamine to find the correct torque setting on your drill so you don’t over-drive the screws (don’t use an impact driver!)
- All your pocket holes should be on the underside of the base and top side of the two cross pieces at the top (don’t know what they’re called) so once you put a top on the carcass it’s all hidden anyway
- On that note, make sure you’re drilling your pocket holes the correct way (they should angle AWAY from the edge of your non-drilled piece

A sheet of 2400x595 16mm melamine from big green shed is about $42 and already has the edge banding on. Melamine glue is about $30. You could just make 1 carcass and see what you think. If it’s not up to your needs then worst case you stick it in the corner and put something light on it. Best case it’s fine for you and you save lots of money!