Thread: Countersink

Steve in Bell,
There is an Australian company Piper Tools who make excellent deburring tools, here is a link to their web site.
http://www.pipertools.com.au/

Regards,
Keith.

For your Aluminium the cross hole type would probably be best,but not really suited for timber.

This type is chatter free.



https://www.woodcraft.com/family.aspx?familyid=5154

Mike

The through hole ones (zero flute) are the way to go, but they have size ranges. You should be able to get local Suttons ones at an Eng/Industrial supplies place. They will cost but last a long time and can be resharpened (peripheral) by a saw doctor for about $8.00 if needed. Alternately can be sharped with a dremel and small stone by expanding the through hole edge.
Cut SS like butter, use the slowest speeds possible, easy to control depth with a depth stop, but the edges of the swarf ribbon will be very sharp so be carefull to break the swarf often so it doesn't get vicious.

Buy a standard 4 flute or 5 flute countersink. You can then use this for woodwork when needed. To stop the chatter in the stainless steel or any metal is very easy. Make sure the hole is aligned with the drill bit and clamp the bar of steel (or whatever the job is) firmly to the drill press table. Tighten the countersink in the drill chuck and check once more for alignment. Now, get a strip of cotten material about 1 1/2 inches or 2 inches wide and about 8 inches long. Fold the strip up so that you have at least six layers of material. Squirt some oil onto the under side of the folded strip and place the cloth over the hole. Bring the countersink down to the material and turn the drill on. Run the drill at about 50 rpm and press down. The cotton stops the teeth from digging into the steel and all the chatter is gone. You may have to press hard at first as the teeth have to penetrate the folds of cloth. This technique will give you perfect countersunk holes. This also works fabulously when starting a big drill in a pilot hole. It works so well that you can actually drill a hole off-center to the original pre-drilled hole.

Kody

thanks eveyone I'll mull everything over and give it a go and see what happens.