Plastics vs. Melamine plywood

[Mark J]

Another thread on melamine has got me thinking.  If glue and finishes don't adhere to melamine then it might be perfect for a "book press" I am thinking about.  I was honestly just going to use waxed paper, but melamine sounds much better.  So a few questions for the oracles.

Is there a different plywood clad material that would make a better surface for glue up?  It would need to be rigid, smooth and flat.

I see melamine plywood is available at the BORG.  Are there quality grades/issues to consider?

Does melamine machine easily?  Or does it chip and crack?  I need to cut the panels down to 12" to 24" round and drill a number of small holes in the surface at precise locations (I plan to use CNC).  

Edited March 14, 2019 by Mark J
Changed the title to reflect evolution of the question.

[Chet]

Would Formica on baltic birch be more durable then melamine?  I say baltic birch because it is a nice smooth surface to adhere the Formica to.

 

[SawDustB]

I don't see any reason not to... Melamine (on particle board) can tend to chip a bit around the edge, but if you use a high tooth count blade you'll get decent results. It's also really cheap, which means that it can be easily replaced if it does fall apart on you. I've used it for a router table fence and a few other things and it's a decent choice. It will stand up better if you put at least the iron on edge banding. I would think that the phenolic coated plywood might also be a good choice, but that tends to be expensive and hard to get. @Chet is right, the Formica is more durable, but it's more work, more expensive, and it is probably not quite as flat.

[Mark J]

Does Formica come pre-made?  I'll look for the phenolic stuff just to check it out.

As to chipping, my concern is chipping during milling.  It's a jig so some wear and tear on the edges probably won't be an issue.

[pkinneb]

Melamine does chip fairly easy while milling if you don't use sharp tools and or tape etc on the edges. It holds up fine for jigs and is cheap enough that I would give it ago if it doesn't hold up to your expectations I'm with Chet BB with laminate glued to it is very durable.

[Byrdie]

Use a laminate trimmer router bit with a pilot to trim the edges of Formica or Melamine.  I also think Freud makes a Melamine blade.  I might even have one.

[Ronn W]

I use melamine for the cauls in my vacuum bag when veneering,  cleans up easily.  Just be sure to store it flat or vertical like hanging on a wall to keep it straight.

I bought the melanine sheets but if you plan to do you own gluing I think I would use MDF instead of plywood.  If the mdf is flat when you get it and you store it flat or vertically, it will stay flat.  I can't say that for some plywood.

[G Ragatz]

3 hours ago, Mark J said:

Does Formica come pre-made? 

Home Depot sells pre-made laminate countertops, under their Hampton Bay brand.  They come in 4- 6- and 8-foot lengths.  They have an edge treatment on the front edge, which you'd need to cut off.  I think the laminate is over a 3/4" particle board substrate.

[Mark J]

Thank you.  Let me evolve the question.  I could also use plastic sheet goods.  Plastic is about as specific a word as is wood, there are numerous varieties.  A bit of searching this morning turned up a variety of materials.  Does anyone have familiarity with any of these?

Polycarbonate (Lexan)

Acrylic (Lucite, Plexiglas)

HDPE (high dens polyethylene)

UHMW (ultra high molecular weight PE)

PVC

Since this is a glue up jig I want material that does not adhere to Titebond type adhesives (I to III), although it would be helpful if I could glue the pladtic together with epoxy or CA.

It needs to be machinable, as I will cut it to shape and drill several holes.

It needs to be smooth surfaced and reasonably rigid, although I could easily back it up with MDF or plywood.

I am thinking 1/4" material, and I expect to have access to a CNC router, although some cutting may be on the bandsaw.

The PVC is particularly interesting as the local Lowes sells 24" x 24" ceiling tiles which would be a convenient size.

[G Ragatz]

I don't have much experience with most of these materials, but I so have a couple of UHMW cutting boards in my kitchen.  They are about 1/4" thick, and are quite rigid.  I think the material would be pretty easy to mill (I can carve a piece off the edge with a kitchen paring knife, no problem) - but it's a thermoplastic, so it might start to melt if you try to cut it/mill it fast.

As a test, I put a couple of drops of Titebond III on one of my cutting boards and let it set up for about 6 hours.  I was able to peel it off easily with my fingernail.

[BillyJack]

On 3/13/2019 at 11:34 AM, Mark J said:

Another thread on melamine has got me thinking.  If glue and finishes don't adhere to melamine then it might be perfect for a "book press" I am thinking about.  I was honestly just going to use waxed paper, but melamine sounds much better.  So a few questions for the oracles.

Is there a different plywood clad material that would make a better surface for glue up?  It would need to be rigid, smooth and flat.

I see melamine plywood is available at the BORG.  Are there quality grades/issues to consider?

Does melamine machine easily?  Or does it chip and crack?  I need to cut the panels down to 12" to 24" round and drill a number of small holes in the surface at precise locations (I plan to use CNC).  

Melamine at the big box is “cold rolled”and isn’t as good as “thermally fused” from a cabinet supplier.

 

How often have you been at the big box and seen a portion of the melamine paper missing. It peels off

[Mark-in-Seattle]

Regarding HDPE plastic.  It is available in rigid panels (1/4" - 1") and thin sheets (0.032" - 0.065" - 0.125") of course.  Menards even sells 1/4in-thk 4'ft -x- 8'ft sheets (approx $77 each) that are likely pretty rigid.  HDPE is quite inert and slippery.  Almost nothing I've used adheres to it.  Joining pieces is accomplished with heat - thermo-welding for a good bond.