Cutting or grind slots in carbide cutters??

[coonhunter]

I need to grind or cut notches into carbide cutters (to tighten set screws against),Do I need to get a surface grinder? what kind of cutter could I use to just mill a slot in them?

[Zumba]

Any tool with an abrasive disk should cut it... angle grinder, dremel, etc. For more precise work, you could try finding/making a mandrel that will fit a 4.5" or 5" cutoff wheel, then mount it to mill.

[Switcher]

You need a diamond wheel for carbide, a CBN wheel for HSS. If you only have a few to grind for yourself look at Ebay and find a used diamond wheel in good shape. You should be able to find one for a bench grinder.

Also is the whole tool carbide, or is the carbide brazed to a steel shank ?

[coonhunter]

Thanks for the info so far.
I thought about a diamond stone but was concerned about not getting a flat surface that is square. I want to make sure when I tighten down on the set screw, that it is set against a true flat surface. Maybe I'am making it harder then it should be.....
The cutters are solid carbide.
I also thought about putting them in v-blocks and mill a flat suface,but not sure what type of cutter to use.
thanks for any and all info.............

[WhiteTiger]

What sort of cutters are you talking about? If it's indexable inserts then you probably don't need a slot at all, since a lot of single point and rotary cutters hold the inserts in place with nothing but screw clamps or wedges.

Like most of this stuff, the devil and the solution are often in the details.


Tiger

[Geof]

Originally Posted by coonhunter I want to make sure when I tighten down on the set screw, that it is set against a true flat surface. Maybe I'am making it harder then it should be.....

I take it you are referring to solid carbide milling cutters and you want a flat on the shank. I think you are worrying more than necessary about getting it truly flat; you can grind a more or less flat spot using a soft grinding wheel. There are designations that can be used on carbide but I cannot recall them just at the moment. Provided you are not running in excess of 10,000 rpm and are not trying to work to plus/minus 0.0002" you do not need to get too finicky.

[little bubba]

Originally Posted by coonhunter Maybe I'am making it harder then it should be..... The cutters are solid carbide. I

Yes you are, for putting flats on endmills, I just use a bench grinder with whatever wheel happens to be on it. We have a green wheel, but that grinder is 220 so I have to walk 100ft to get to it. You don't need a monster flat, a Weldon flat is pretty much overkill. You don't even need a really flat flat, just something for the setscrew to bite into. The only time I've run into any sort of problem doing this is on small endmills that have tiny little setscrews in the holders, 1/4" and smaller, they work fine, for normal milling and ramp fine, but they will move when plunging. 3/8 diameter endmills and above, never a problem.

[Jay Kyle]

The 'green wheel' little_bubba referred to is a silicon oxide grinding stone for your benchtop grinder you can buy at your local tool store for grinding carbide. And beleive me, it grinds carbide like butter! but you sure go through the wheel fast.

Jay

[coonhunter]

The thing I was worrying about was the cutter going into corners that may have extra meat in them and flexing a little over time and work the set srew loose.
I will try a green wheel.
Thanks for the help

[little bubba]

You don't need a green wheel to put a little flat on. Save that expensive greenwheel(not that bad $60-$100?) for putting radiuses and chamfers on endmills or customizing a lathe insert. They are handy, but I won't walk that 100ft to it for a reason, its expensive and I want it in as nice a condition as it can be for detail work, its very rare that you put a flat on an endmill with any thought as to what the wheel is going through, just stuff it in there and if you beat up an $8 wheel, who cares, you've got your flat.

[Jay Kyle]

Expensive? I paid $19 for my 6 inch green wheel at house of tools in Calgary.