How crucial is it to laminate both sides of a work surface?

[ryan.s]

I'm building a couple of shop fixtures and had a question about work surfaces. For the outfeed/assembly table I'm planning to use 2 sheets of 3/4 mdf laminated as the surface supported by legs and aprons. I wanted to top it with plastic laminate and have always heard that if you should always laminate both sides of the table top to avoid warping. Does this apply to MDF as well or would it not be necessary in this case? Considering the cost of plastic laminate I'm not sure if I want to spring for two sheets. The dimensions of the top will be 3'X5' with aprons/stretchers every foot and a half. What's the best glue to use on plastic laminates?

On a similar not I'm also building a miter saw hutch but will be using one sheet of 3/4 MDF as the top supported on a sub top constructed with 2Xs on top of ply. Same design as the hutch on New Yankee Workshop. Planning to coat the top with poly or laquer and was wondering if both sides of the mdf needs to be coated?

Thanks!

[cgallery]

You gotta do both sides. But you can do the hidden side with backer (mica w/o the finish layer--cheaper).

[LinuxRandal]

Not trying to highjack, but this goes kinda along with it.

I am looking at building a worktable with Melamine (thought about MDF and laminate, but this is quicker). I need a fairly slick service, to help move larger items on, so Melamine is winning out, but with either laminate, or melamine, do I need to seal the ends, chemically, if I am edging with hardwood?

I understand the moisture issue, if laminating one side, but what about the sides themselves?

Thanks

[RodKirby]

If you want "it" to stay flat you MUST finish both faces - the same way.

laminate+laminate or paint+paint. The back laminate can be el-cheapo.

The idea is to make sure any "movement" is the same - front and back.

[RodKirby]

Not trying to highjack, but this goes kinda along with it.

I am looking at building a worktable with Melamine (thought about MDF and laminate, but this is quicker). I need a fairly slick service, to help move larger items on, so Melamine is winning out, but with either laminate, or melamine, do I need to seal the ends, chemically, if I am edging with hardwood?

I understand the moisture issue, if laminating one side, but what about the sides themselves?

Thanks

Where I have done this - melamine + hardwood edge; I just put a single coat of wipe-on ploy on the hardwood to stop fingerprints/dirt appearing.

[cgallery]

Not trying to highjack, but this goes kinda along with it.

I am looking at building a worktable with Melamine (thought about MDF and laminate, but this is quicker). I need a fairly slick service, to help move larger items on, so Melamine is winning out, but with either laminate, or melamine, do I need to seal the ends, chemically, if I am edging with hardwood?

I understand the moisture issue, if laminating one side, but what about the sides themselves?

Thanks

No, you can wrap hardwood edging around the edges w/o having to treat the substrate with anything. Though, most people will use a little glue between the edging and the substrate to hold better than nails alone.

[ryan.s]

Dang, I was hoping I could get away with doing just one side but I guess that's not gonna happen now. Thanks for the suggestions on getting a lower grade laminate.

So just to confirm if I just laquer or poly one side I should also do the other as well?

[gsmittle]

Dang, I was hoping I could get away with doing just one side but I guess that's not gonna happen now. Thanks for the suggestions on getting a lower grade laminate.

So just to confirm if I just laquer or poly one side I should also do the other as well?

Yep, ya gotta do both sides. DAMHIKT.

g.

[Uncle Cracker]

I have actually had good success with work surfaces made with double-layered MDF, laminated sides and edges with formica, and bottoms coated with a good layer of fiberglass resin. Still nice and flat after 5 years in Florida humidity.

[cabinetman]

I'm building a couple of shop fixtures and had a question about work surfaces. For the outfeed/assembly table I'm planning to use 2 sheets of 3/4 mdf laminated as the surface supported by legs and aprons. I wanted to top it with plastic laminate and have always heard that if you should always laminate both sides of the table top to avoid warping. Does this apply to MDF as well or would it not be necessary in this case? Considering the cost of plastic laminate I'm not sure if I want to spring for two sheets. The dimensions of the top will be 3'X5' with aprons/stretchers every foot and a half. What's the best glue to use on plastic laminates?

On a similar not I'm also building a miter saw hutch but will be using one sheet of 3/4 MDF as the top supported on a sub top constructed with 2Xs on top of ply. Same design as the hutch on New Yankee Workshop. Planning to coat the top with poly or laquer and was wondering if both sides of the mdf needs to be coated?

Thanks!

If you are doubling up 3/4" MDF, it won't be necessary to laminate any backs, especially if you have underbracing to screw the bottom sheet of MDF. Use TB II between the sheets of MDF, and solvent based contact cement for laminating the Formica.
.

[TheRic]

If you are doubling up 3/4" MDF, it won't be necessary to laminate any backs, especially if you have underbracing to screw the bottom sheet of MDF. Use TB II between the sheets of MDF, and solvent based contact cement for laminating the Formica.
.

Why in this case doesn't the back need to be laminated?? Because of MDF? Overall thickness (1.5")? Double sheets? etc?

[atgcpaul]

Why in this case doesn't the back need to be laminated?? Because of MDF? Overall thickness (1.5")? Double sheets? etc?

1) Seasonal changes shouldn't affect plastic laminate and gluing with rubber
cement lets it "float" over the MDF.
2) Doubled up MDF is pretty rigid stuff and is already very stable for starters.
3) Securing to a stiff base will help hold it all flat.

The OP could make a torsion box like this one made by my WWing teacher,
Brendan. http://www.proguild.com/articles/torsionbox.pdf No way that things
is ever going to warp.

Paul

[SARGE..g-47]

I agree that both sides should be done.. but I don't think it necessary that the same material has to be used to seal it. I have laminated tops on several work cabinet table surfaces that were 3 coated with un-cut poly on the bottom side.

They have not warped in numerous years of use, leading me to conclude that "sealed is sealed".....

Regards...

[cabinetman]

Why in this case doesn't the back need to be laminated?? Because of MDF? Overall thickness (1.5")? Double sheets? etc?

The principles in this procedure support the properties of the MDF. Gluing two pieces together eliminates one surface on both pieces. With a grid of support for the bottom piece, there is more than enough restraint to keep the two pieces flat.

As in making counter tops out of either plywood, particle board, or MDF, being screwed along the front and back edges, and wherever there are cross members, keeps a laminated top flat. I can't count the number of counter tops I have done and none were laminated on the back unless it was for a visual reason.
.

[Black wallnut]

Although finishing both sides the same is ideal I am not sure it is necessary. On many of my projects over the years I have only finished the top side and have never noticed any ill effects. This has been with solid wood, plywood and mdf. In all my years I do not believe that I have ever seen a kitchen counter with laminate applied to both the top and bottom and yet all these counters have remained flat in an environment with widely fluctating humidity swings.