Cutting down endmills?

Just grind out the center area and hand them to him. Seriously, way too much time, effort, and used up wheels for the end result, IMO. Reliable tool or find a trade, or, if the 5/8 DE mills are worth a shit, sell them. What brand and how many? I could use a few if they meet criteria.

michael

Haven't heard back on the pup, but have another fish smelling the bait.

I must be missing something here. If you grind down the center of a two-flute endmill, how is he going to hold it in a 1/2" collet or endmill holder? Both sides of the endmill will still be 5/8", no?

Jim Kovar Vulcan, Mi

Heh. How about cut them in half with a cutoff wheel, and then reduce the diameter of the new *end* sections instead?

Jim

================================================== please reply to: JRR(zero) at yktvmv (dot) vnet (dot) ibm (dot) com ==================================================

Gunner,

I've e-mailed you about this.

Geez, is this a troll? If you have a 5/8 double ended end mill and grind the center to 1/2 inch, how are you going to use them? If this isn't a troll, I would just call the guy up and admit it is not feasable to grind down double ended end mills. And that you thought they would be single end end mills when you talked to him. He can go to reliable tools just as easily as you can.

Dan

How about potting them in lead or plastic? I have used jeweler's hard machinable wax for similar situations.

P.S. Did you get the puppy pix?

Pick whichever end is in better shape, and cut the lesser end off! Now, you still have a holding problem, but maybe you could just hold the cutter end in a 5/8" collet. Are these center cutting? Then, there's no center hole in either end, anyway. The only way I know to make a "dead nuts" accurate cutter is to put a center hole in each end, and then regrind the cutting flutes to be concentric to the center holes.

Jon

Thats the Idea. How do I hold the endmills so they can be ground on the collet end? Two flutes remember.

Gunner

That rifle hanging on the wall of the working-class flat or labourer's cottage is the symbol of democracy. It is our job to see that it stays there. - George Orwell

Ah, but you missed the stupidity of it all! Doing a double ended end mill is a stupid thing to do in the first place. If you do it right then one of the ends is destroyed in the process. If you do what he wants - namely grinding down the clamping area - he ends up with a tool that he spent money on that is now unusable.

-- Bob May Losing weight is easy! If you ever want to lose weight, eat and drink less. Works every time it is tried!

Could you feasibly cut them in half, then hold the freshly cut end of each to grind down the rest of the non-fluted bit, and finally cut off the tip you held it by?

-tih

There isn't enough shank left after you cut them in two, so that you could hold on a straight portion and still have enough left over to reduce the diameter on? If that's really the case I think this is one of those "you can't get there from here" sorts of things. :(

Jim

================================================== please reply to: JRR(zero) at yktvmv (dot) vnet (dot) ibm (dot) com ==================================================

Bob May is right, you will probably ruin them. I went out to the shop and grabbed a Brubaker 2 flute 5/8" double endmill. If you cut it in half right in the middle of the flat, you will end up with a little over

Jim Kovar Vulcan, Mi

Sounds like a job for a centerless grinder which you apparently don't have.

Suggest you send them back with your sincerest apologies. Or find someone with a centerless grinder to do the job?

Hmm.

Add a hole or two near the end of the endmill. Put a rod through this.

Cast the end in the hardest metal that melts at under 200C. Grab the middle normally, now trim it to cylindrical. Put this end in a collet. Grind away, slowly and with lots of coolant. Melt off end.

Gunner, sounds like you got your learning experience!

RJ

what about making a reverse center cup for both ends. then the endmill should self center in the cup and the outside end will have centers for the grinder. only thing though is how to drive the mill which i considered using maybe a dowel pin through the end of the cup but i'm not sure.

I'd chop off one end and use the whole center for the good end. Pick the sucker end. Measure standard lengths before cutting -

I'd think about using a collet to hold the cutter end and grip it tight enough to grind back the the other end.

I had a tough time doing that for a friend on a single end - Gripping half on the big end and then rotating 180 and doing the rest.

The best finish I got was using an oiled stone in my post hole grinder. Oil runs cooler and does better fine cutting. [ e.g. not expanding the metal and cutting - cuts cold. ]

Martin

If you grind into the flutes, it will work. This is what I did to the test pieces. Holding the flutes in a 5c..thats the problem when there is only two of them. Worked fine with a 4 flute and a 6 flute.

Gunner

That rifle hanging on the wall of the working-class flat or labourer's cottage is the symbol of democracy. It is our job to see that it stays there. - George Orwell

Indeed.

Gunner

That rifle hanging on the wall of the working-class flat or labourer's cottage is the symbol of democracy. It is our job to see that it stays there. - George Orwell