Mdf.....

[Ken Fitzgerald]

Will regular old Titebond work when gluing MDF?

When I glue 2 pieces together, can I use the same woodscrews I normally would if I predrill holes?

I am working with MDF for the first time.

Thanks!

[Bruce Page]

It works very well with MDF.

[John TenEyck]

Works for me, Ken. Just use lots of glue if you are gluing to the end grain. Also, it's best to use coarse thread screws and be careful not to over tighten them lest they strip.

John

[Andrew Pitonyak]

I did some tests with MDF..... and I:



Drilled a hole
Tapped the hole
Dribbled in some CA glue to harden the threads.
I think that I sent the tap down again after the glue hardened.


I was then able to use a non-wood screw in the MDF.

[Kevin Bourque]

If you are gluing up the boards for thickness, try using brad nails toe-nailed into the MDF instead of screws.

[Richard Coers]

I double glue the end grain. Apply a coat, let it sit for a minute, then add a little more. Don't drill as close to the end as you would with plywood or solid wood. Countersink is a necessity. The skin is really hard and a screw won't pull into the face.

[Larry Kunkler]

Hello everyone. I think this is my first post here on the creek...So hello again.

I built a pair of speaker support boxes ~ 30 yrs. ago. 1/2" high quality veneered MDF open bottom boxes about 1' sq. with full mitered edges all round. these boxes were assembled with Tightbond-1 without any fasteners. I still use them for step stools to reach stuff on my shelves to this day. the joints are still perfect (did i mention i weigh a good 220#s). Imo you might be better off with a good glue up and just a few 18ga pins just for easier assembly...kunk

[Prashun Patel]

I've found screws in mdf to create a ridge on the leaving piece that is hard to compress around and thereby bring the pieces tight. And of course, when you try to torque the screw to bring the pieces tight, they can spin out. I've had worryfree results by countersinking the hole in the backside of the leaving piece.

[glenn bradley]

TB-I and TB-II work fine for MDF. The thing about screws is that you do not want any wedge-like force. You want the threads only to cut into the material to avoid splitting if going into ends/edges. It is also recommended that the hole be slightly deeper than the screw is long. Again, this prevent the screw form forcing itself into the material. MDF has not grain fibers to resist splitting. Also, take care of the volcanoes that Prashun mentions prior to assembly.

I used 7/64" pilot holes, countersunk and 1/4" deeper than the screw was long. Regular old drywall screws and TB-I. Other fixtures use McFeely's #8 FHWS and TB-II with the same pilot method except using an 1/8" bit as the McFeely's shafts are 1/8" less the threads. All units still in daily service with no failures.

[Tom Leftley]

My experience with MDF is that a woodscrew doesn't work very well because it is tapered.
I have had good luck using machine or sheet metal screws which are the same thickness for the full length.

Predrilling a pilot hole is required.

I have had good luck with Titebond glue. Be sure to apply glue to both surfaces and then clamp the joint tightly.

Good luck.

[Jeff Duncan]

Short answer is yes, yellow glue and screws can and do work in mdf. However it really depends on exactly what your trying to do! I treat mdf differently for different needs. Hardware for instance requires euro screws in my shop. Screwing one piece into another for anything structural requires pre-drilling and counter boring. Even SPAX screws will split mdf! MDF can be a great material for certain uses, you just have to know what works and what doesn't;).

good luck,
JeffD

[Kurt Cady]

If gluing for thickness, I predrill and then do very slight counter sinks on both of the faces getting glue. Allows the little nibs that get pushed out by the screws a place to escape.

[Kurt Cady]

I've found screws in mdf to create a ridge on the leaving piece that is hard to compress around and thereby bring the pieces tight. And of course, when you try to torque the screw to bring the pieces tight, they can spin out. I've had worryfree results by countersinking the hole in the backside of the leaving piece.

This is why I slightly countersink those faces

[Rich Engelhardt]

MDF takes glue well.

For screws, I prefer to use Kreg coarse pocket hole screws. I drill a hole first, then go back and use a larger drill bit the same size as the head of the pocket hole screw as a counter sink to counter sinke the head below the surface. A smear of drywall mud and you'll never know a screw is there.

Drywall screws will work, but, the bugle head can leave a bulge.

[Chris Padilla]

http://www.mcfeelys.com/confirmat-mdf-screws

Confirmat screws work well in MDF. MDF has all sorts issues because it is so dense.

What is the project, Ken? I suggest you seal (use cheap/leftover paint or poly or whatever) the MDF well, too. It will absorb moisture in time and could move on you.

[Joseph Tarantino]

agree that mdf doesn't like moisture, but i've never had it "move" on me like dimensional lumber (which is probably why Nahm used it as floating panels in cabinet doors) and it absolutely doesn't like to get wet. the crown molding i fabricated for a bathroom hasn't swelled or absorbed any moisture in three years. it was, however, painted before the shower was used. a piece of trim by the kitchen sink got wet before i could paint it and it will have to be replaced.

[Roy Turbett]

Works great but I don't use screws, just two brad nails to line things up and some clamps. A couple of grains of sand also helps to keep the pieces from sliding around when you're doing your glue up. I use MDF to fabricate belt guards for old woodworking machines and it works great.

[Peter Aeschliman]

+100 on countersinking both sides of each workpeice. I also agree that brads are even better. The screws won't help with strength after the glue dries, so why hassle with them?

[John Coloccia]

+100 on countersinking both sides of each workpeice. I also agree that brads are even better. The screws won't help with strength after the glue dries, so why hassle with them?

Another +1 on this. If you're going to screw, definitely countersink the second board as well or it will never work right.

[Ken Fitzgerald]

Chris...I am building Norm Abram's Deluxe Router Station for my shop. I am using MDF for the fences. They will be covered with high pressure laminate on the working face. I am also using T-track instead routing T-slots like Norm did.

The body will be made of 3/4" oak plywood.

The top will be made of 1" thick corian, CNC cut for the Woodpecker lift, the T-tracks for the adjustable fence and miter slots for miter gauge track.

It will take a few weeks as I work slow and yard work time has started to develop here as it has warmed up.

[Myk Rian]

I use sheet metal screws with MDF, and counter sink for the heads. That way it doesn't create a bump where the screw went in.

[Peter Aeschliman]

Ken, if you're face-gluing MDF for the fence, the key is a very good glue-up. If the fence isn't flat after the glue up, MDF can be difficult to make flat after the fact. So I recommend spreading the glue very thinly and evenly, and applying even clamping pressure (lots of clamps, but not too tight).

One mistake I've made with MDF is assuming it's flat. It's just like any material- it's not always flat from the lumber yard. The good thing about MDF is that if it's flat, it will likely stay flat if supported properly. But it doesn't always start flat!

I have a love/hate relationship with MDF.

Cons:


You have to do a lot of extra stuff to deal with fasteners (countersinking, keep away from edges, using glue if you want to tap for threads, doesn't like threaded inserts, etc). It strips out easily, so fasteners can be a challenge. There are solutions, it just takes more thought and planning.
The dust is horrible
Heavy/difficult to manage full sheets
Hates moisture
Will sag if not properly supported- it's not a very rigid material. I used it for my router table and it sagged pretty quickly, even at 1 1/2" thick- you'll need to support it with webbing underneath, kind of like a torsion box. I added some perfectly flat hardwood webbing to the bottom and it straightened right now and hasn't sagged since.
End "grain" is difficult to paint or finish- it sucks the finish up like crazy.
The edges are very soft and can dent. Definitely chamfer exposed corners.

Pro's

Inexpensive
Heavy (this is both a benefit and a drawback, depending on application!)
Faces take paint very well
Dimensionally stable- it doesn't expand and contract or twist as much as other materials in normal shop/home conditions (excluding super high humidity areas like bathrooms). But like I said, it will sag if you don't support it adequately.


I use MDF all the time, don't get me wrong. You just have to chose the application carefully!