Laminating MDF

[Marc Prudhomme]

Hi
There was some advice on how I should glue together 2 3/4 MDF sheets.Something about rigging up pipe clamps to the ceiling.Does anyone have any clear instructions on just how I go about doing that?I was trying to avoid using screws..

[Art Mann]

I will tell you what I did when I glued two layers of MDF together for a router table. I used a small hydraulic jack to press the two layers together. I placed the two pieces of MDF on my bench top, which is very flat and stiff. I spread Titebond glue between the 2 pieces with a trowel used for flooring adhesive. I used 2 2X4 pieces stood on edge as cauls with a third piece between them to form the shape of an "H". I then located the jack on the center of the H cross piece. I then cut and placed another piece of 2X4 vertically that was just long enough to reach from the jack to a ceiling joist. Then, I just jacked up the vertical 2X4 to apply downward force on the cauls. You must be careful about locating the vertical 2X4 and use discretion pumping up the jack as even a small jack can easily poke a hole in the ceiling or break something with too much force.

I hope this makes sense!

Art

[Bart Leetch]

Real simple not complicated at all.

1. Cut the 2 pieces of material a little over sized.

2. Place bottom piece upside down on bottom of top sheet.

3. Align sheets clamp mark grid & pre drill & countersink holes.

4. Apply thin layer of glue to both pieces of material clamp together shoot screws home starting in middle of sheet working toward the edges. You can remove or leave as many screws in as you wish when the glue dries.

I used this method for my Unisaw extension table & the router table in the left wing.

I used a tablesaw top to clamp both tops to as they dried.

The tops came out nice & flat.

I wrapped them in oak & topped them with pewter colored laminate & installed them.

[Norman Hitt]

I used "EXACTLY" the same procedure Bart described above when I built my friend a Router Table Cabinet and Top. (I did use three cauls to clamp the pieces to the saw top to keep everything flat til I got the screws in). I removed all screws after the glue was dry and filled the holes with Spackling Compound, wrapped all 4 edges with 3/4" x 1 1/2" oak, then sanded the spackling flush and covered both the top and bottom with white laminate, and used a router with a 45* bit to trim the laminate and ease the edges. It came out perfect.

[Alan Turner]

I make a third vote for the screws method. This is how I built the PFW router table top, which is tight and dead flat. I think I had the screws on a 4" grid, but it might have been 6". After the glue was dry, the screws were removed.

One trick here is that after drilling through the bottom of the bottom with a taperd coutersink bit, I then made a very slight countersink cut on the top of the bottom (i.e., the inside of the sandwich), so that when you run the screws in, the slight puffiness you see on mdf when screwing without drilling will have somewherre to go without forcing the pieces apart.

[Marc Prudhomme]

that makes sence AL.Thats a lot of holes though for a 5 1/2 ft x 3 ft table.but I guess if I want it flat I am going to have to work at it one way or another.
I make a third vote for the screws method. This is how I built the PFW router table top, which is tight and dead flat. I think I had the screws on a 4" grid, but it might have been 6". After the glue was dry, the screws were removed.

One trick here is that after drilling through the bottom of the bottom with a taperd coutersink bit, I then made a very slight countersink cut on the top of the bottom (i.e., the inside of the sandwich), so that when you run the screws in, the slight puffiness you see on mdf when screwing without drilling will have somewherre to go without forcing the pieces apart.

[Sam Chambers]

I used my brad nailer and a few screws when I laminated MDF for my router table extension.

Not trying to hijack the thread or anything, but I was wondering...Bart, I have the same setup as yours - Unisaw, no cast iron extension on the left, router table on the left - and am installing a new Biesemeyer fence. I can't tell from the photo, but does your setup have legs to support the far left end of your router table?

[Marc Prudhomme]

I am thinking about going with the solid core door but I cant find one at the right price.Right now I am looking at $20 a sheet for the MDF and $30 for the Flooring material.

[Joe Spear]

I laminated two sheets of MDF together for my 34" x 28" router table top with contact cement. I did it on a Corian kitchen island counter as a work base and didn't have to clamp it. I also laminated formica onto the top and the bottom with contact cement and glued on 1"-thick purpleheart edging with Titebond III. It is very flat.

[Frank Chaffee]

1-1/2” thick MDF is available from suppliers of cabinet shops. Two people *can* move a full sheet, but it is not fun. If the supplier would cut the size you need, it may be something to consider.

That stuff is very slippery, and the best gloves I found to handle it are the ones with little rubber nubbies on the palm side.

[Rick Lizek]

The ceiling thing...it's called go bars!
http://www.stewmac.com/shop/Tools/Clamps,_support_tools/Go-bar_Clamping_System.html

[Marc Prudhomme]

I am thinking about going wit the screw option.Would general purpose drywall screws be good with the mdf(what size?)I will be removing them after the glue sets. Whats the best glue?

[Jim Thiel]

Titebond and aggressive threads.

Jim

[Marc Prudhomme]

Thinking going about every 6 inches .Sheets are 3x5 ft.Think thats enough?

[Marc Prudhomme]

you have to remember guys I am a serious greenhorn.Tightbond,is that a type of yellow glue?Who makes it?

[Mike Heidrick]

Titebond is the brand name of the yellow glue. They have a few types (I, II, III). check out their site at www.titebond.com (http://www.titebond.com) for more info on the types of glue they make and their purpose. I use original type I and type II. 3'X5' will take quite a bit of glue - get a gallon. Also a crad scraper for drywall compund sold at home centers for a buck is a great way to spread out the glue, that and a glue roller (bottle to hold glue with a plastic roller at the tip).

[Marc Prudhomme]

Thanks Mike,
I really need the heavy explainations.I had laminated a couple pieces of plywood on my old table and it started to come apart.I just want to get it right this time.I plan on putting hardwood flooring on top of that MDF.Could I use the same glue?I think this question was answered befor ,Im not sure.
Thx Marc

[Scott Thomas]

Wouldn't be easier to just lay the panel on the floor or a table and put some cinder blocks on top of them?

[Jim O'Dell]

Marc, I find the gallon size of Titebond at Home Depot are decently priced. May have to go to Woodcraft, Rockler, or mail order for the glue bottle with roller though. Can't remember if HD had them or not. Jim.

[Howard Acheson]

Use contact cement to laminate MDF or particleboard. In the shop I was involved with we made maybe 500 or more counter tops for kitchens and bank teller stations and tables. All were made with solvent based contact cement. They are still in use with no failures. Other shops I am familier with all use contact cement. Contact cement is fast and easy and no concerns with clamping.

In my shop, I have a set up table made from two thicknesses of MDF and a router table made from two thicknesses of PB. Both are over 10 years old.

I don't see why one would want to use a PVA adhesive to laminate PB or MDF. The contact cement is more than strong enough and so much easier.