formica on plywood edge?

[keith ouellette]

I have a piece of mdf and it is going to be surrounded by a skirt of 1/2" cabinet grade ply wood where the plywood edge is flush with the surface of the mdf.

I want to cover that with formica, using contact cement to bond it.

Will that bond to the plywood edge well enough or do I need to treat the plywood edge with something first?

[Michael Pyron]

just make sure to apply the contact cement twice to the plywood....also make sure it is ripped with a quality blade that leaves a nice edge (i.e. no tear outs) and sand flush with the MDF (evil stuff IMHO)...I would suggest using the solvent based contact cement as opposed to water based as I don't think the MDF will react all that well to the water based version....

[keith ouellette]

just make sure to apply the contact cement twice to the plywood....also make sure it is ripped with a quality blade that leaves a nice edge (i.e. no tear outs) and sand flush with the MDF (evil stuff IMHO)...I would suggest using the solvent based contact cement as opposed to water based as I don't think the MDF will react all that well to the water based version....

Is that to fill the pores of the plywood edge?

[Tom Veatch]

Keith, some of the plywood I've cut turned out with the edges of the internal plies looking more like corncobs than wood. So, yes, the advice to use two coats of contact cement is to fill the wood.

However, even that may not be enough to get a good bond depending on just how smooth the cut edge is. I suggest that you do an on-purpose fill job on those edges. I have used regular waterbased paste wood filler - Elmer's Carpenters Wood Filler, I believe - thinned out to a brushable consistency to fill the rough edges of plywood. Paint on a good thick coat, let it dry thoroughly, and sand smooth. Admittedly, I've never used it under contact cement and formica, and someone may know of a reason that it' not advisable. But I would make a effort to fill the edges and get a smooth surface before applying the cement.

[Tony Bilello]

If the plywood edge is lesser than desired, I use autombile Bondo to fill in the areas. Bondo can be used successfully to fill in small gaps and to 'rebuild' bad corners in plywood, Particle Board and MDF prior to laminating.
Mixed properly, you can sand, sculpt and go over the Bondo with laminate in about 10 minutes.
All I ever use for plastic laminate is solvent based Contact Cement.

[Quinn McCarthy]

Keith,

Make sure that you do the edges first and sand them flat with the top on the substrate. Then put your top piece over that. That way you can stop moisture from penetrating into the edge and causing damage. I hope I didn't just offend you but I have seen it done the wrong way and after a while the edge pieces are falling off and the substrate is damaged.

Quinn

[Michael Pyron]

Is that to fill the pores of the plywood edge?

actually I said coat the ply twice because it absorbs the contact cement and needs 2 coats to leave the proper amount on the surface to create a proper bond...as other posters have mentioned fill any voids in the ply with a good filler (bondo sounds like a good choice, I just used some Fakowood because its solvent based and dries quicker than a water based filler), and of course as another poster mentioned sand flush with the MDF...if your anal allow the project to sit for a day then sand again as I bet a slight ridge develops (this would be exacerbated if you sand the joint while the wood glue is still curing (which can take over 48 hours))...follow the directions for the contact cement in regards to the probability of needing 2 coats (I bet the MDF will tend to soak it up also, though if the outer layer is hard like some is it may not need the second coat of adhesive)

I just did a rather odd shaped formica counter top for a cabinet I built (on which the only square thing is the partitions for the openings...every edge of the top is out of parallel with its opposite side...the hard part was getting it into the area between 2 half walls where it now resides ) and used AC grade plywood for all of it, which included the dropped edge (which I glued on and stapled the he!! out of), the back splashes and the toe board...it came out just fine though because I let my router roll up a bit I had to re-do one of the back splashed because the bit burned through the formica...

[Timothy McDonough]

My kitchen countertops have red oak as the edge banding that is attached to 3/4" particle board. Cleats were attached to the bottom of the particle board and the red oak was glued and screwed to the cleats from the underside so that the screws did not show. The oak edge banding was sanded flush with the top of the particle board. Then formica was glued to the top of the particle board and the oak edge banding, using solvent based contact cement. The formica was trimmed flush with flush cutting router bit and the edge was routed with 1/4" round over bit. I painted the underside with three coats of an oil base paint and I stained the red oak to match the color of the formica.The countertop has held up very well about 15 years now. I hope this helps.

[Jason White]

What I've seen done (and I think it looks better) is to cover the edge of the plywood with a strip of hardwood, apply formica on top, then use a chamfering bit on a router to make the transition between the hardwood and formica look pretty.

Jason


I have a piece of mdf and it is going to be surrounded by a skirt of 1/2" cabinet grade ply wood where the plywood edge is flush with the surface of the mdf.

I want to cover that with formica, using contact cement to bond it.

Will that bond to the plywood edge well enough or do I need to treat the plywood edge with something first?