die grinder loading up

JohnJL · 10-08-2005, 05:40 PM

A call for help from my machinist colleagues...

I am boatailing my main webs and my steel die grinder bits/burrs keep loading up with alu between the blades. Is there a trick to getting the alu out from between the blades? Heat it up and quench?

thanks

TimT · 10-08-2005, 05:50 PM

Are you cutting dry?

if so thats a no-no

you need some cutting fluid... you can buy it or make your own

a recipe to make your own is some ATF some H2O, mix and shake till you have a nice emulsion. IM sure others will inject some insight

dip the burr in it between cuts

jim72911t · 10-08-2005, 06:29 PM

Yup, sounds like you are cutting dry, which will melt the aluminum rather than cut it. Not too difficult to do with the RPM's that the die grinders can create. I'd suggest a cutting fluid as well. When I'm machining on my manual mill, often times I will spray some WD-40 on the cutting tool. Works pretty well, but it stinks and makes a mess.

I'd also suggest taking light passes rather than trying to hog out cuts.

As far as getting the aluminum out from the flutes on your cutting tools, I've had some success with prying the material out with a small screwdriver and some pliers. Once you get it started, the aluminum will usually pull completely out of the flute. Great fun.

Hopefully, you haven't dulled the cutting edges of your cutters too much with the heat. If so, the cutters will continue to cause problems. Time to throw them away and start fresh.

Good luck,
Jim

MACHINEMON · 10-08-2005, 06:45 PM

Wax is not too bad in a pinch....

84toy · 10-08-2005, 06:55 PM

Cutting dry is no problem with the right cutter. I ported two stroke cylinders for years. There are aluminum specific cutters where the cutter "teeth" are not so close and that reduces the load up problem of the cutter. Wax does work good. When the bit is warm, stick it in the wax and do so frequently. Now if you are using a $5.00 cutter from your local hardware store, it probably crapped out in the first 2 minutes. A good quality cutter is quite expensive.

911pcars · 10-08-2005, 07:30 PM

I've used bee's wax; also a bar of soap. Since it's thin, I think cutting fluid is best used for continuous cutting, as in drilling or milling operations.

Are you using carbide tools?

Sherwood

JohnJL · 10-08-2005, 07:53 PM

THanks all for the replies. I was cutting dry, as recommended by the owner of the bits (who I will now return to him alu gratis!).

I did try heating them up til red-hot and quenching. This dropped the alu out, but it soon built up again.

Now I know...will try the suggestions next time.

911pcars · 10-08-2005, 11:52 PM

As an aside, heating a metal to a red hot temperature, then quenching it changes the temper and hardness of the material. You don't want to expose cutting tools (expensive ones anyway) to these temperatures and temp. extremes.

Sherwood

P Clingman · 10-09-2005, 02:46 AM

Just run the cutter on some steel after this will remove the alum.
Never heat up a cutter this distroys the heat treating. You
have to slow the cutter speed down or use coolant or a cutter
for alum at your die grinder speed. Palmer

North · 10-09-2005, 07:44 AM

Again, never heat up a cutter, quench it, then turn it up to 20k RPM. Bad news.

Get not ferrus cutters designed for aluminum, wood etc. The righ tool will make it easy as pie.

Removing aluminum can be done by cutting up some scrap steel.

randywebb · 10-09-2005, 11:01 AM

We used kerosene on Al when I took courses in being a machinist...

goose2 · 10-09-2005, 11:29 AM

Microcrystaline wax is the best solution I've found...it's used in "lost wax" casting processes. Pattern makers, jewelry makers, small foundries, metal sculptors should have it. You've probably ruined your cutters by heating them red hot. Heating tool steel and quenching will make it very hard and brittle..maybe ok for cutting alum but nothing harder.
Randy