Thread: Best drill bit for 60mm mdf

What about a forstner bit? That's what I'd use.

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I’d probably go with a hole saw without knowing more about the situation.

Originally Posted by mic-d

I’d probably go with a hole saw without knowing more about the situation.

This, probably quickets, cheapest and easiest.

a 60mm forstner bit will require a bit of grunt to churn through 60mm of MDF. A battery drill will probably do it but just depends on how many holes you have to do



could also use a jig and a router

I'd go hole saw (preferably tungsten tipped) over a Forstner.

Tip: Drilling two 12mm diameter holes diametrically opposite each other kissing the outer circumference of the hole will enable the hole saw to continually clear sawdust and keep cutting without the need to repeatedly move the saw in and out of the hole.

I’d use a 60mm Forstner bit:

Forstner bit high quality 2-3/8" 60mm - Robson'''s Tool King Store



Regards,

Brian

What homey said - a 60mm forstner will make the neatest hole cut to exact size. Ideally clamp the workpiece down on a pillar drill and set the drill to a very low speed, gently does it. If the workpiece is too big to fit on a pillar drill, and you must use a handheld battery drill, select the slower "screwing in" speed on the drill when using a bit that size.

Otherwise, you may Gromit Drilling.flv - YouTube

Hole Saw

None ofmy holes saws will drill 60 mm depth - so you would probably need to drill from both sides. Such a lot of friction at depth would make a drill press almost mandatory - with a lot of debris clearance.


Forstner Bit

Probably a good option in a drill press with frequent debris clearance. Beware of break out on exit side.


Alternative Method

Rough out hole with a jig saw.
Make template and finesse hole with straight cutter router bit with bearing.

Ha - I read 60 mm diameter - not 60mm deep. The OP does writesay "the holes themselves will be 60mm" but I'm not 100% sure what this means.

I'd use one of these: Ripper TCT Hole Saw | Bordo – Sharp Edge Aust

The standard serrated tooth hole saws are horrible for cutting wood. I haven't tried Bob's trick, but the hole saws in my link have no trouble clearing the sawdust. They also have a deeper depth of cut so you should be able to go all the way through from one side.

If the substrate thickness is too deep for the hole saw you're allowed to back it out and remove the waste. With mdf it's pretty easy to insert a screwdriver and break off the top bit. Either a Forstner or hole saw will do the job.

edit. Assuming you can get to the other side it's better to finish from the other side anyway. Centre drill doesn't go through? Drill pilot hole through with another drill the same size and finish from the other side.

I've got a bunch of these Torquata TCT forstners and they are really good - although the 60mm version will cost you a shiny penny. https://www.timbecon.com.au/torquata...ing-drill-bits. I've used upto 42mm in a drill press, had no issues with the quality of cut or runout.

When I need an odd large size like I did when I wanted 62mm and a 50 something? size for a couple of holes on my workbench construction I made the bits by welding leaf spring steel to 12.7 mm rod.
The grind is like a spade bit but the center point is not sharp like a bought spade bit. Its a spigot the size of a 4 or 5mm drill bit. So I mark a center point, drill a 4 or 5m hole, I forget exact size of spigot atm. The spade bit follows that pilot hole. I made them about 300mm long. I drilled through something like 75 mm Jarrah with them.
I call them my spigot bits. The closest similar thing I've seen is a metal workers counter bore with the spigot end on them.
5pcs Counterbore Drill Bits Set, 4 Flutes Straight End Mill Cutter HSS Countersink Slot End Mill Cutter M3-M8 for Copper Aluminum Cast Iron : Amazon.com.au: Home Improvement

I also made round end versions with no spigot. These are used after a hole is drilled to finish the bottom of a hole neat and rounded. Like a spoon bit does.

left pic was taken while making the rounded ones. With some round bottomed holes. The bottom bit is the spade / spigot.
IMG_0775a.jpg

And an end view.
IMG_0776a.jpg

Originally Posted by jack620

The standard serrated tooth hole saws are horrible for cutting wood.

Fully agree. Just too much friction. Using them in a drill press reduces the friction, but still not a good tool to use.

Have not seen the Ripper TCT Hole Saws but have taken note of them and Bob's technique for future reference.

These Fisch bits are excellent (but that's reflected in the price...). https://www.timbecon.com.au/fisch-wa...-forstner-bits

Reasonable speed on a clamped workpiece in a drill press, and keep clearing waste as you go will give a good quality cut. Don't worry about break out - clamp a sacrificial piece of MDF underneath, and drill straight through into that. That'll give about as clean a cut as possible if you want a neat, precise job. (If it is an option, I tend to finish holes like this with a 45 degree chamfer bit in a trim router, and just ease the edge of the circumference a mm or so - looks very smart, and stops the edges crumbling/chipping in day-to-day use...)