Struggling to cut 35mm hinge holes in MR MDF - Advice please

[Stevie B]

Hello everybody,
It's time for my first post so I hope you can help.
I'm finding it very difficult to cut neat 35mm holes into 18mm MR MDF for concealed hinges on some wardrobe doors that I have made.
I'm using MR boards as that is all my local merchant now stocks.
I've tried several different hinge cutters of slightly differing designs and price points but all of them are struggling, they just get blocked up within a second or two and I am having to press down so hard that the holes are not as accurate as they should be and its even hurt my wrist!
I'm using a cordless drill but think it might be better using a router attachment if one is available?
Is MR MDF very different from standard MDF as I never used to struggle like this or all all my cutters just rubbish?
Any tool/technique tips or advice would be greatly appreciated as it seems such a simple task but it's doing my head in! (hammer)

Also while we're on the subject of MDF, does anybody use the lightweight MDF for making built in units or wardrobes etc? Is it any good for that type of application and is it good to work with?

Thanks a lot guys
Steve

 

[custard]

If you're pressing hard then your hinge cutter is likely blunt, it should cut like a hot knife through butter, luckily most forstner style bits are dead easy to sharpen. It's surprising how many drill bits come, if not actually blunt, then certainly well below optimum sharpness. Just in the past month I've had a Festool countersink and a Famag forstner that were brand new but weren't cutting at all well. A quick touch up with some slipstones and they sizzled!

Personally I'd prefer to use a router or a drill press, but I know plenty of people use cordless drills on site and seem to get acceptable results, I guess cup hinges cover a multitude of sins!

 

[Adam9453]

I'd agree sounds like blunt drill bits or possibly an underpowered drill. If you just bought the cutters then I'd take them back and return them, if they're old then re-sharpen as mentioned above. As a general rule of thumb you shouldn't ever really have to press hard when drilling, it's usually a sign something's not right.

 

[petermillard]

Hi & welcome.

MR MDF is a much better quality board for not much more money, so it shouldn't be a problem with the material; I'd agree that it sounds more like a bunt bit. I make a *lot* of doors from MR MDF and I've always bought relatively cheap cutters e.g. Faithful (about £8 apiece from eBay) and just chucked them when they start to struggle. Haven't cut hinge holes with a cordless for a while, but I remember it helped to rock the drill from side to side slightly to get the cutter started. Make sure you use a depth stop too; very easy to over-drill in 18mm - even if you don't go all the way through you can easily get a 'pimple' on the face side from the centering tip...

HTH Pete

 

[SteveF]

I would also consider drilling a hole through some pine of something similar first and clamping to your mdf to stop the wandering

unless someone say don't bother

Steve

 

[Lons]

I don't make my own doors these days but buy in vinyl wrapped MR doors for kitchens and I have to drill all of them. I use a good quality forstner which cuts easy, clean and accurate holes. In my experience, it's difficult to get a dead accurate cut with a forstner in a hand drill. I do a lot but use my pillar drill and have made up a simple jig for repeatable results.

cheers
Bob

 

[Zeddedhed]

Like a few of the others who've posted here I also drill lots of these holes - up to 50 a week. some time ago I invested in a EuroDrill - a simple clamp on jig from Blum that has a variable edge distance thingy and also guide holes for the fixing points. I have found that when drilling into Caber MDF (sold by my local Alsford Timber) it takes much more effort than when drilling into Medite. It could be that this is what you are experiencing rather than a blunt bit. With a new bit in Medite it's all over in about three seconds. With a new bit in Caber it's in, clear it, in, clear it, in (pushing like a madman), clear it etc etc.

By the way, the drill in question is an 18v cordless Makita three speed jobbie.

 

[worn thumbs]

I would tend to agree with the diagnosis of a blunt bit.A few years ago I had to make a new oak door for a kitchen unit as the original suppliers were no longer around.I bought a Forstner style bit at a show and expected it to work.It didn't,even in a pillar drill.I spent a bit of time with a diamond slipstone creating a cutting edge where it had never existed and tried again.Much better and the door is still fine.I would be apprehensive about sinking a hinge with a hand held drill and it is asking quite a lot of a cordless.

 

[Kev]

Agree with all others, sounds like blunt cutter. Have cut a fair few of these in MR MDF and as long as it is sharp (does need constant touching up with a diamond stone) then should not be a problem. Also find it cuts better in pillar drill if you have one.

 

[Mike Vastano]

I struggled with a forstner bit ended up buying a router bit Much much easier and with the fence much more accurate

 

[Stevie B]

Hello all
Many thanks for all your replies to my problem with what should be such a simple task!
I'm using a 4ah dewalt cordless so its definitely not underpowered and I've tried at least 4 different cutters, 2 of which have been brand new, 1 was a forstner bit and the other was a S&J hinge cutter which was the most effective.
I'm having the problem exactly as zeddedhed described, it's in with the cutter, clear it, in again for another couple of turns, clear it etc etc and funnily enough it is caberwood MDF.
I do like the idea of a router cutter so maybe I'll invest in one as I'm being asked a lot more to make wardrobes and cupboards now.
I might post some pics of these when they're finished, although they're taking an age as they're a my house and I don't get enough time to do it!
Thanks again guys

P.s any thoughts from anybody on using the lightweight MDF?

 

[MatthewRedStars]

P.s any thoughts from anybody on using the lightweight MDF?

The cut edges can be very fluffy and void-y.

I'd only use instead of thicker sheets, greater than 25 mm. (I can move a 25mm sheet without killing myself, just)

 

[Alf Beharie]

Just a thought...Why not use plywood instead of MDF? Ply offers several advantages...Even a blunt Forstner bit will drill into ply like a knife through butter. Ply would be better for making cabinets for use in areas where damp can be a problem like kitchens and especially bathrooms as MDF sucks up water like sponge. You can seal the MDF with several coats of button polish, like we used to do in the film industry, but its an extra process costing time and money that you have to factor in. Most hardwood ply is also faced with a nice natural woodgrain which can be easily finished with a few coats of satin varnish whereas varnished MDF just looks like cr*p!
Factor in that MDF is second only to Asbestos for producing dangerously toxic fine dust particles, causing lung disease, lung cancer and putting many a chippy into an early grave, then why you would even use the stuff is beyond me? Price? I'd rather pay a bit more and live longer!

 

[MatthewRedStars]

Factor in that MDF is second only to Asbestos for producing dangerously toxic fine dust particles, causing lung disease, lung cancer and putting many a chippy into an early grave, then why you would even use the stuff is beyond me? Price? I'd rather pay a bit more and live longer!

Bit dramatic - all fine dusts are dangerous. MDF has very little unpolymerised formaldehyde in it, so it's essentially no worse than plain old wood dust.

We should protect against all dusts.

 

[stuartpaul]

Factor in that MDF is second only to Asbestos for producing dangerously toxic fine dust particles, causing lung disease, lung cancer and putting many a chippy into an early grave, then why you would even use the stuff is beyond me? Price? I'd rather pay a bit more and live longer!

Bit dramatic - all fine dusts are dangerous. MDF has very little unpolymerised formaldehyde in it, so it's essentially no worse than plain old wood dust.

We should protect against all dusts.

+1

I do rather dislike this 'MDF kills everything' approach. Much better to be cautious of all dusts and bear in mind the HSE limits are based on exposure throughout an 8 hour working day and most of us are unlikely to be exposed to anywhere near that level.

 

[wide74]

A hand drill will be fine in any MDF if your bit is good quality. I have Festool and Famag forstner bits which will drill virtually anything with a cordless no worries. If you're struggling in mdf then the bit is blunt. End of.

Cheers.