A good Forstner bit needed

[Dengue]

Can anyone please recommend a good Forstner bit? The set I have are not much good for cutting holes in MDF or ply - they clog up very quickly. In making a hole in 18mm MDF, I have to clear the bit three times. It is done in a drill press.

I have attached photos of a sample bit from my set.

regards,
Jill

[chippy 71]

Can anyone please recommend a good Forstner bit? The set I have are not much good for cutting holes in MDF or ply - they clog up very quickly. In making a hole in 18mm MDF, I have to clear the bit three times. It is done in a drill press.

I have attached photos of a sample bit from my set.

regards,
Jill

Jill, I have two types, both are sawtooth Forstner bits, one lot bought from Carba-tec which does not have a brand name and the other brand name is Carb-i-Tool, both equally as good.

Regards,
Colin.

[HazzaB]

Hey Jill,

Looks like about 20mm bit in the pics, would a spade bit do your job?? by the way way how many holes are you doing??

HazzaB

[Ashore]

When I did the dog holees in my bench 30mm of chipboard wit a 6mm masonite on top , normal forsteners did not last , paid $45 for a vermont and did all the rest without a problem or re sharpen
:2tsup:

[Dengue]

Thanks for this ashore. I can't find any reference on Google to a Vermont bit. Do you have a photos? Where did you buy it, and do they come in many sizes?

regards,
Jill

[BobL]

MDF is real nuisance to drill out with a forstner bit. If insufficient pressure is applied the bit makes a lot of dust which gets trapped under the bit and inhibits the cutting action. If too much pressure is applied the chips can jam in the bit. Effective cutting is then usually a matter of the right pressure.

Some MDF also seems to be dustier than other and crumbles rather than making nice spirals. In these situations I locate a flexy DC outlet within inches of the hole and stop every now and then an suck out the dust from the hole.

[issatree]

Hi JillB,
Not being a woodworker, but I do use the Saw Tooth Bits mainly. They are very easy to Sharpen quickly with a Red Easy Lap Sharpener, by holding it in a vice, & with good lighting.
I'm always told that my Drill is going to fast, when I use them.
I think the speed should be below 250 rpm. I use a small bit of wood when using these bits, so I can remove the waste as it appears above the hole, & of course you have to remove the bit quite often while drilling, & that is also the time I use my little stick to clean the bit as it is going.
I in fact, never use MDF, as it is to hazardous. The dust is a KILLER.
Probably telling you how to suck eggs, eh ?.
Regards,
issatree.
<input id="gwProxy" type="hidden"><!--Session data--><input onclick="jsCall();" id="jsProxy" type="hidden">

[snapman007]

I use a bi-metal hole saw.

[Christos]

I have both saw tooth and not the saw tooth. :) First time I purchased one set I did not know the difference but the ones with the saw tooth I perfer.

Now for both I put a little bit of wax on the round outside part seems to cut a little better especially on the larger holes.

[Ashore]

Thanks for this ashore. I can't find any reference on Google to a Vermont bit. Do you have a photos? Where did you buy it, and do they come in many sizes?

regards,
Jill
There a yankey brand try "vermont tools " I got mine at a shop called 'tool city' in newcastle but they have been taken over by gasweld .
As you alluded to quality costs but is worth every penny :2tsup:

[Drillit]

Hi,
In my experience forstners and MDF are a problem. What I have done is to buy a spade bit grind off the outside spurs and the centre point - and away you go. You can even regrind them so that they are similar to a forstner but the angle from centre point to edge will give you better clearance. Also the modified spade can be used on lathe for end turning. If you are not drilling right through you could drill it with the spade as modified and then finish with the forstner preferably with saw teeth to give a bit more grip and take out the centre point mark. I am sure you know how toxic MDF dust is - so suggest you take the usual precautions. Hope this helps and that I have explained what I meant. John M.:)