need quick response...please help

[Midnite Mick]

I am currently drilling 1.5 inch holes in the internal speaker braces consisting of 3/4 inch MDF. I am using a 1.5 inch hole saw on a drill press. It is really burning the wood/glue of the mdf as it is cutting. Is this normal and is there something that I can do to minimize this as the odour is somewhat intolerable. Doesn't look very professional either.

Thanks
Mike

[pinkmouse]

Hole saws burn just about everything. You could try knocking the speed right down on your drill, but I mostly use Forstner bits these days to get around the problem.

[Midnite Mick]

Originally posted by pinkmouse
Hole saws burn just about everything. You could try knocking the speed right down on your drill, but I mostly use Forstner bits these days to get around the problem.

I see. Then it isn't just me. Are Forstner bits those thick spiral ones or the blade typed with the pointed lead.

Mike

[Relax]

Slowing down the drill speed or just hogging through will help. Although really pushing through will make it very rough.

[F1 FAN]

I have had this happen to me as well .It can get real hot from the friction .Maybe You can try it with the speed your drill press slowed down some. What I do is start the cut to half depth with the hole saw then use the circle as a guide and finish it with a jig saw.

And yes burned MDF is not pleasant smelling.

[pinkmouse]

Originally posted by Midnite Mick
Are Forstner bits those thick spiral ones or the blade typed with the pointed lead.

A forstner bit, (Google is your friend! ):

[Midnite Mick]

Thanks all appreciate it. Yes your right I was being lazy. I should have looked up the Forstner bit myself.

Mike

[audio-kraut]

It also helps to slowly drill through about 1/2 the thickness, then turn the piece around (when possilble) and use the pilothole as a guide drilling from the opposite side.
Works well for me.
I drill a lot using holesaws, mostly into studs and joists/osb. But MDF is another matter.
For anything bigger than 12/2 I use a router and the circle guide.

[Midnite Mick]

That Forstner bit went through like butter. It hardly got warm at all. After this experience I will never use another hole saw again unless I absolutley have to.

Thank you,
Mike

[ptwining]

Guess I'm a bit late here but you don't need to buy a new tool. Just use the ones you got a little better. Buying new tools to solve every problem is expensive.

The answer is to use a paddle bit (or whatever you have) to drill a relief hole at the inside edge of your hole saw cut diameter to let the MDF dust out of the cut.

Forstner bit is not a bad thought but if you ain't got one here is a simple solution.

Here...

Make your first buzz with the hole saw about 2 mm into the material, remove the workpiece and put a paddle-bit drill hole exactly on the edge (inside the diameter of your hole saw cut) such that a hole (inside the diameter) is created. Thus the MDF dust has a relief hole thru the workpiece to fall out of before it burns. Works every time.

This I know from long experience.

Have I made myself clear? Sometimes I get a bit obtuse, wordy-like...

Regards,
Tom