Drilling 35mm holes in MR MDF for concealed hinges

[Dan Steely]

Hi All,

After not touching MDF in anger in 20+ years, and following a heavy dose of Peter Millard videos, I've bought a couple of sheets of MRMDF for some projects.

The first one, a bathroom cabinet, needed 4 concealed hinges for the doors.
I bought a cheap positioning jig and did a few trial runs with the forstner type bit but had to keep stopping the drill to remove the MDF fluff detritus and could not drill in one go. I tried other forstner bits and suffered the same problem. Obviously not the end of the World but it's a bit of a pain.
Is there a remedy to this?

PS: I remember seeing in a PM vid where he had setup a bench drill to make the door holes but don't remember him having to stop to clear the 'fluff'.

Many thanks.

 

[eribaMotters]

I use a carbide tipped drill in my pillar drill. I generally back off on downwards pressure and withdraw the bit part way through to allow waste to escape.

Colin

 

[petermillard]

Hi All,

After not touching MDF in anger in 20+ years, and following a heavy dose of Peter Millard videos, I've bought a couple of sheets of MRMDF for some projects.

The first one, a bathroom cabinet, needed 4 concealed hinges for the doors.
I bought a cheap positioning jig and did a few trial runs with the forstner type bit but had to keep stopping the drill to remove the MDF fluff detritus and could not drill in one go. I tried other forstner bits and suffered the same problem. Obviously not the end of the World but it's a bit of a pain.
Is there a remedy to this?

PS: I remember seeing in a PM vid where he had setup a bench drill to make the door holes but don't remember him having to stop to clear the 'fluff'.

Many thanks.

I just use a bog-standard hinge boring bit in the pillar drill, nothing special about it. Never had any issues clearing the debris - MRMDF should still cleanly without any fluffiness. Was it branded MRMDF?

 

[Sideways]

Tried one of the chinese carbide boring bits around this size. Cheap. Sharp. It made a super clean hole in birch ply but poor quality carbide chipped on the very first hole.

 

[baldkev]

ive found the cheaper grade of mdf ( mr included ) will come away in layers with my hinge bit ( trend ) whereas the better quality medite or caberwood pro cuts fine.
Another option is router and jig, but for 4 holes......

 

[TRITON]

What a fantastic scenario to be in

An opportunity to buy something

Kreg, so will be in pretty good accuracy.

 

[TheTiddles]

I’ve found the same thing.
Hinge boring bits appear to have more clearance than the forstner bits I have.

 

[Dan Steely]

Thanks for all your thoughts on this.
So me thinks the tools and technique are probably OK and my issues are down to the substrate.
The MRMDF in question was purchased between Christmas & New Year 21 when the only supplier available was my local builders merchants. It is moisture resistant MDF, greenish in colour and 18mm that actually measures 19mm and cost £40.00 inc VAT for a 8'x4' sheet.
So not Medite then... (BTW: what is the street price for a 18mm sheet?)
I'll talk to some proper wood suppliers next week (Totton Timber & Arnwood Timber in Southampton) and will try and source a different manufacturer and compare the results.
Thanks all.

P.S. I've just found a PM video where he talks about the Kreg jig and briefly shows his bench drill setup drilling a hinge pocket. The MDF looked like it came off in pencil sharpener type strips. That was not my experience...
(setup shown at 1:13)

 

[John Brown]

I made some cupboards for the shed a couple of months back. Used standard MDF and had the same problems with drilling the holes. Next time I'll splash out on Mr. MDF.

 

[TheTiddles]

Totton timber 18mm MRMDF is almost double what you last paid currently

 

[petermillard]

P.S. I've just found a PM video where he talks about the Kreg jig and briefly shows his bench drill setup drilling a hinge pocket. The MDF looked like it came off in pencil sharpener type strips. That was not my experience...
(setup shown at 1:13)

Is it green all through, or just a green core? All through it’s probably Caber, maybe Kronospan. Haven't used Caber for years, but all the MR I’ve used does the ‘pencil-shavings’ type of cut.

 

[baldkev]

Theres different grades. Caberwood trade is cheaper woolly stuff. Caberwood pro is more dense ( more resin ) and machines better. Medite is a touch better again. I havent used kronospan etc, its hard enough getting caberwood pro around here!

 

[Ollie78]

I recently suffered with some MR MDF I got from Travis Perkis because I couldn`t find any nearby and couldn`t be bothered to go to Timbmet.
I think it was Caber stuff. Never again it was just garbage to cut drill and paint.
It was clearly lacking in resin and was super fluffy and had visible differences in the particle size. The Kronospan I normally get is twice the density and super even all the way through.
Wouldn`t have minded if it was even cheap, which it was not.

Ollie

 

[baldkev]

That'll be caberwood trade. Theres not much in it as far as price goes, so i dont know why they bother. I only discovered that there was denser stuff a few years ago, around here they only stock the trade. I was in a joiners shop and we cut up some tricoya, i mentioned the rubbish we usually get and he enlightened me. I can get caber pro about 45 minutes from here or order stuff in. Although jewsons supply medite, there's never any available when i want it ordered in and our other local yard has stopped stocking caber trade as prices are too high!
Theres an independent called southern timber and they will deliver ( about 40 minutes away ) they are better stocked than jewsons!
Just before xmas i had to drive up to jewsons exeter for a load of caber pro and they have oak up there!! We never get anything like that here