Hi Sean what material are you milling and what machine are you using to mill on. I would rough out with a smaller rougher cutter and then finish with a nice new new sharpe cutter.

David

When you say steel, is it mild steel, leaded, tool steel, gauge plate. Is it going to be hardened. I would use the horizontal on some thing like this it needs just setting up one cut and change the part to do a batch of holders.

David

Edited By David George 1 on 26/05/2018 21:23:47

Won't help for this job, but all carbide mills can be bought for £10 on the bay from a UK source. Is it worth getting a new one instead of a poor re-ground one? Could well be cheaper in terms of frustration…

Regards

Richard.

 

Dave- I wondered about that cover- looked like a flywheel in a 3 jaw while a dremel in toolpost grinds the internal bore…? I didn’t come up with a reason why though… or why the high carbon flywheel…

-Richard

Sorry for off topic…

Edited By RichardN on 27/05/2018 12:09:58

Mark, you cheated and read whet it says on the cover. Dremel in a toolpost holder grinding chuck jaws held in position with a spider not a flywheel, maybe people should buy the mag

A 4 flute endmill is not good practice when cutting a slot. In general there is too much swarf to cope with when there are 4 flutes or more. 3 flutes or less is better for slot cutting. If you take lots of small cuts , so in the region of 1 to 1.5mm deep the 4 flute will cut a slot. But in general a slot drill cutter will take about 50% of it's diameter as a depth of cut, like cutting a key way . I never bother with the wavy sided roughing cutters. For a 12mm slot, I would use a 10mm 3 flute end mill/Uni Mill cutter, and then go down it with a nice 12mm cutter. If the size of the slot is important, then using a new or very good condition 10mm cutter , 4 flute or 6 flute and finish the sides of the slot that way with a 1.0X cut off the centre line each way until it is at size. Most carbide cutters are about 0.02 to 0.03mm in diameter undersized anyway.

With tool steels, or steels harder than free machine MS, often the depth of cut is about 1/2 and the feedrate is about 20% less with a surface cutting speed also about 20% less maybe more depending on the steel and the sturdyness of the mill and set up.

Neil

Definitely not a Photoshop job. Those old Burnerd chuck jaws were made of some good carbon steel. Captured on a Nikon point-and-shoot camera by yours truly. Took a bit of time to capture the sparks just so, but I had plenty of time while taking tiny fairy cuts with the Dremel under fine feed with chuck rotating at 30rpm or so.

Edited By Hopper on 29/05/2018 02:27:35

An excellent photo Hopper. Having tried to take similar I know catching sparks on camera ain't easy.

My suggestion that the front cover was Photoshopped has me wearing sack-cloth and ashes. No excuses, I looked at the picture and didn't read the words…