Working with a Carbide Countersink

[CZKnives]

I have recently spent way too much time trying to track down a very particular countersink bit. Although I have found through browsing the forums that cobalt seems to be a better material for knife making, I can only seem to find a countersink with my crazy specifications in carbide. I have heard a few things about carbide chipping, it being brittle, etc. and considering the price of this countersink, I would like to not screw it up. I am cutting annealed D2 steel, at 760 rpm, witch is the slowest my drill press will run, with Monroe Fluid Technology cool tool 2 (of witch I have no information about either), the countersink is a 6 flute, 1-1/2 diameter carbide countersink. any advice on the subject would be greatly appreciated!

 

[Nathan the Machinist]

A carbide countersink, fed manually in a small drill press, might not last very long in D2. That is a narrow processing window. Feed it hard enough to keep it cutting, not rubbing, but not so hard you overload a cutting edge and chip it. The cut feed rate is dependent on the cut diameter some, but it's probably going to be around 10-15 IPM on a 6 flute at that speed.

A thick cutting oil might help damp some of the vibration. Vibration kills carbide. But re-cutting chips kills carbide too, so be careful using a lubrication.

Please let us know how this works out.

 

[CZKnives]

A carbide countersink, fed manually in a small drill press, might not last very long in D2. That is a narrow processing window. Feed it hard enough to keep it cutting, not rubbing, but not so hard you overload a cutting edge and chip it. The cut feed rate is dependent on the cut diameter some, but it's probably going to be around 10-15 IPM on a 6 flute at that speed.

A thick cutting oil might help damp some of the vibration. Vibration kills carbide. But re-cutting chips kills carbide too, so be careful using a lubrication.

Please let us know how this works out.

I will, Thank you for your help! However this may be a mute point as a retailer has been helping me track one down in cobalt. So if I find one I will most likely get one of those, as I am somewhat of a newbie and would like something I can bang around a little. Additionally do you have any preference over cutting fluid? or are they all about the same in the long run.