Modifications to Key Cutter

[thestelster]

I need to cut a 3/4" t-slot (sort of), very close to a tall vertical wood surface. The endmills I have aren't long enough, and the collet chuck won't let me get close enough. But, I can chuck my ER11 collect chuck in the ER40 collet chuck, and chuck the key cutter. Except the cutter is a 1/2" shank, and the maximum size for ER11 is 1/4".

Ok, lets just reduce the shank of the cutter.

 

[thestelster]

Of course, it wasn't the best set up, but it was quick and dirty, well, maybe just dirty!!
I used carbide inserts. I have CBN inserts, which would have been optimal, if I had the D inserts, which I don't. I also had to reverse the direction of carriage travel, and angled the insert tool (because Idon't have a left handed D insert tool) to get close to the teeth of the key cutter.

 

[PeterT]

Looks great. I bought a CBN insert for another purpose but have not yet tried it yet.
Is the cutter body itself typical HSS? Doesn't look like the shank put up too much fight. Was the outer skin hard but got easier as you cut towards the core? I've heard some tools are fully hardened & tempered, others more local to the cutting business end. I guess you don't know till you try. I've seen guys reduce HSS drill shanks with carbide but they didn't last very long. I guess it varies by case.

 

[thestelster]

Looks great. I bought a CBN insert for another purpose but have not yet tried it yet.
Is the cutter body itself typical HSS? Doesn't look like the shank put up too much fight. Was the outer skin hard but got easier as you cut towards the core? I've heard some tools are fully hardened & tempered, others more local to the cutting business end. I guess you don't know till you try. I've seen guys reduce HSS drill shanks with carbide but they didn't last very long. I guess it varies by case.

Oh, it was complaining!! Through hardened. And it seemed harder near the neck. You can see where the insert wouldn't cut that area and left a bulge. I was able to reduce it a bit with the cut-off blade running it like a turning tool.

 

[thestelster]

After reducing the shank to 0.255", I put it between centers on the Tool and Cutter Grinder and tried to manually cylindrical grind it. A little dangerous but it worked well enough.

 

[thestelster]

And it worked pretty well. Of coarse it was only cutting wood.