MDF screws and glue.....

[Boatfixer]

I have just got a job which will involve screwing and glueing a lot of MDF together, with screws going into the edge of the MDF panels. My normal go to screw and glue for general woodwork are Reisser Cutter screws and Everbuild D4 PVA. Is there a better choice for this job?
Thanks
Graham

 

[Dave D]

I have not come across Reissler screws before so thanks for the post. Its good to know about them.
I recently completed a similar construction though using something completely different.

The job was a bunk bed with a built in staircase for my granddaughter made using Confirmat screws from Screwfix and no glue.

They do require pilot and clearance holes and you can buy fancy drill to do them simultaneously.
I just clamped the parts together and drilled a pilot hole through both, then a clearance hole, then screwed in the Confimat screw.

The great advantage for me was that I could make the bed at home then dismantle it for transport to her bedroom for quick assembly while she waited impatiently to stress test it.

It passed the stress test with flying colours and can be dismantled again for modifications as she grows up or just for redecoration of the room.

This might be overkill for your job but its nice to have alternatives for different jobs.

 

[Ring]

I like using plasterboard screws seem to really pull up tight with them.
Jim

 

[Phil Pascoe]

The problem with plasterboard screws is that if you use them somewhere important like a KD fixing or a hinge and the head breaks off (which they do), you can have a pig of a job to either get the screw out or move the fitting somewhere else. You can also guarantee that they only snap in an awkward place.

 

[oakfield]

I use spax MDF screws. They have a torx head and can be screwed straight into the edge of MDF without a pilot hole and without splitting or bulging.

 

[Newbie_Neil]

Hi Graham,

My normal go to screw and glue for general woodwork are Reisser Cutter screws

I also use Reisser and have found that they are excellent for working in board materials.

The marketing blurb says, "The Reisser Cutter yellow Screw benefits from having a unique design with 2 slots cut into the thread on 30mm and above screws (1 cut up to 25mm). This allows the screw to work closer to the edge of both timber and board materials without splitting." (My highlight)

HTH,
Neil

 

[petermillard]

+1 for Spax M-Cut screws. PolyTen PVA works well for me.

Pete

 

[Phil Pascoe]

Everbuild D4 is a seriously underrated adhesive, imo.

 

[hansonread]

I us Wurth Assy+ screws, they require no pilot hole, although if its a very visible fixing on a finished product then a pilot hole and countersink never goes a miss, they are far cheaper than the spax screws, however more outlay in the fist place due to pack size. I can send you some samples if you liked? I have hundreds of boxes knocking about.

 

[RobinBHM]

I've always used confirmat screws for mdf which I buy from Hafele, the stepped drills are stupidly expensive though.

The spax M-Cut screws are interesting I'll buy some to try.

 

[beaver]

+1 for reisser screws and d4

 

[Kev]

i am a big fan of the Reisser Screws and work well on both solid and board materials. No piloting needed and more importantly hard ever cause splitting. Don't think there is much between Reisser and Spax myself but as Reisser are cheaper I go for those ( I use a lot!!!!).

Kev

 

[GLFaria]

Might a glued in hardwood dowel be acceptable as an anchoring means for the screws? Lots of work, I know, but I never really liked the idea of screws in the edge of MDF.

 

[Mar_mite]

I use various brands, spax and reisser are both excellent, as are the goldscrews from screwfix. But I think having the right pilot bit is the most important. I use a 3mm hss bit, drill all the way in, no countersink. Even a cheap silver 2" 8 will pull up. I think I read smoothing about flashy branded screws improving battery life if drills. Like a drill would drive say 300 cheap silver screws but 500 spaxs.

 

[Mar_mite]

Might a glued in hardwood dowel be acceptable as an anchoring means for the screws? Lots of work, I know, but I never really liked the idea of screws in the edge of MDF.

That's nuts. If mdf edges couldn't take a screw, I would be out work.

 

[Boatfixer]

Thanks for all the input folks. This job is a bit different to my usual racing dinghy refurbishment...... It is a large batch of pidgeon hole type racking for a customers mail order warehouse. There are over 200 sheets of MDF involved! I am having all the material cut and the shelf housings cnc routed so I just have to assemble them. I like the look of the conformat screws but to be honest I think probably overkill for this job. It doesnt need to be pretty, just solid and I am hoping that the glue will be the main component of that strength. In fact the man doing the machining for me is recommending for the 6 mm back panels that I glue and use annular ring nails. The main frames are all 18 mm with 12 mm shelving in routed housings.
I'm glad to hear other people like the D4 Everbuild. I am thinking though that as I will be throwing these together as quickly as I can perhaps a construction glue in a cartridge gun might be easier and fill any gaps..... Lay a quick bead in the housing grooves, drop in the shelf and two screws to hold it whilst it sets.... I imagine PVA would need spreading on both surfaces neatly where the construction adhesive would just squish out if a bead was just laid down one surface. Any thoughts on this as an idea?

 

[Mar_mite]

Do you mean like gripfill? No, that would make a terrible mess. Pva in the housings. And a bead on the back. Yes, ring nails hold quite well in mdf. Fine for a back.

 

[Phil Pascoe]

All the instructions I've read for PVA's have specifically said "apply to one side only". I've raised this point before, but no one has come up with a reason. Still, it must be OK or it wouldn't be recommended. As far as using a gun adhesive is concerned, it would be difficult to pull the joints up tight - you might get away with closing up polyurethane, but on a complicated glue up it would start to blow before the joints were tight. Also, PVA is easy to wipe off where you don't want it - some others are horrible to clean up.

 

[Boatfixer]

One down, 46 to go.... Reisser screws are working well. I am not sure with the ring nails holding the back - I am using 25 mm to hold the 6mm panel on but they seem to go in very easily if you know what I mean. I might just screw them on.

My main problem is handling these things - I had a mate lined up to help but he has let me down so I am doing them on my own.

Does anyone have a favourite glue spreading technique? I have tried brush, foam brush and roller bottle. The roller bottle seemed fastest but spread such a thin layer I was worried about the open time by the time I had lined things up and screwed in all the joints.

 

[petermillard]

Are you gluing the backs on as well as nailing? If so the nails are just to hold it together while the glue dries; also, that looks like regular MDF rather than MR, so you'd expect the core to be quite soft, hence the ring nails going in easily. FWIW every MDF item I've ever made has the back simply stapled on, as long as it was glued as well. I've never had a failure...

HTH Pete