5/16 Annular Cutter

[Richard D]

I drill and tap a lot of 3/8-16 holes in steel. I have a drill chuck I can adapt to my mag drill, but it is a hassle, have to take several parts off to do it. I did a Google search but only one hit, the page header said five sixteens, but the listing said fifteen sixteenths, so I'm thinking the header was a typo. Does anyone know where I can find a cutter in this size, with a 3/4" shank?

 

[metaleltr]

would there be any way to adapt a 4 flute center cutting end mill to fit in the mag drill? A collet adapter of some sort? Should work as well as an annular cutter

 

[DekeT]

Will something like this work?

http://www.victornet.com/alphabetic/Annular-Cutter-Holders/1861.html

 

[Just_George]

Easy...

 

[sk farmer]

evolution #evomcs-7, a seven piece mini cutter set for use in hand drills with sizes 5/16 -3/4

 

[Rock knocker]

I don't think you'll find a broach for a mag drill in 5/16". Not enough room there for the wall thickness of the hole saw and the pilot.

 

[Under_Pressure]

would there be any way to adapt a 4 flute center cutting end mill to fit in the mag drill? A collet adapter of some sort? Should work as well as an annular cutter

Depending on the mag drill in question, you may be able to use a morse taper end mill arbor like this. That could work if you figure out a way to find center since you won't have a pilot to go off of like on an annular cutter. You would need to have a drill that accepts the appropriate morse taper and has sufficient clearance/travel to accommodate the bulk of the arbor.

 

[PT Doc]

Easy...

this seems to be the solution. Norseman makes them.

 

[Just_George]

this seems to be the solution. Norseman makes them.

The one I posted is made by Champion, but I'm sure there are several manufacturers. I've used them a lot in my mag drill and love 'em...they work great.

 

[Richard D]

My mag drill has 3/4" hole with two setscrews, so most of those won't work. I think a 5/16 endmill with a 3/4 shank(if such a thing exists) will be the solution.

 

[metaleltr]

Another wild idea, take piece of 3/4 bar stock, cuck in a lathe and drill a hole through the middle, grind two flat spots like on an annular cutter, cut lengthwise with a bandsaw, use in your drill as a collet to hold the endmill, the clearance created by the saw kerf should allow clamping of the mill in the arbor of the magdrill

 

[bsg]

Richard,

How thick of material are drilling and tapping?
I think a annular cutter would be very slow.
We used to machine a lot of steel and aluminum plates, we would drill them on the mill then tap with a cordless drill.
The only concession we would make is drill the hole about .005 over the standard tap drill size, and use plenty of coolant or lube.

Kevin