ER Collet block question

[homebrewed]

Is the body of a typical collet block hardened? I'm looking at one as a component in something I'm thinking about making and it would be most convenient if the block can be drilled for a dowel pin on one side.

 

[cathead]

I can't answer your question but I have made a number of 5C collet holders and have been using them for years.
They hold up just fine in normal use.

 

[BGHansen]

I don't have a set of ER collet blocks, just 5-C and they are hard. A file just skates over them.

Bruce

 

[Manual Mac]

I use ER32 collets a lot.
I bought a block to use them in my mill vise, a cheap one, I think I paid 20 bucks for it, & got what I paid for.
i took about a thou off with a face mill to square it up a little better.
It proved to be very hard, but i think it is drillable.

 

[NCjeeper]

I have import brand collet holders. My 5c are hardened. My er32 are not.

 

[mmcmdl]

Yes , hardened and ground . Could you possibly drill and tap for a set screw ? You could definately drill it , but tapping may be an issue . You could go with a roll pin or dowel . Hard to say not knowing what the desired results are .

 

[homebrewed]

Yes , hardened and ground . Could you possibly drill and tap for a set screw ? You could definately drill it , but tapping may be an issue . You could go with a roll pin or dowel . Hard to say not knowing what the desired results are .

It would be handy if the metal could be tapped as well, but there are workarounds if that's not possible.

I'm thinking about a fixture for making custom milling cutters, all the way from countersinks to tapered end mills. I'd use O-1 or its equivalent, cut (straight) flutes then harden & temper the tool. A precision block would make it much easier to fabricate multi-fluted cutters.

The block would either be mounted on a rotating stage or be drilled for a dowel pin that would be used as a pivot. The work would be turned to the deisired angle for what I want to make -- 45 degrees for a 90 degree countersink, all the way down to a few degrees to fabricate single-tooth gear cutters. Zero degrees would give me a reamer. I'd also use an indexing ring attached to the work to rotate it +/- a few degres in order to get my relief angles -- that's where the drilled/tapped hole in the block would come into play.

Before milling it, the work piece would be turned on my lathe to make a correctly-angled cone on the business end...except for reamers, that is. They really aren't my focus anyway

I'm in the what-if stage so just mulling over some ideas. I can do the same thing by making my own block and holding the work with set screws, but an ER collet block would make it a lot easier to use different-diameter stock. But the other side of the coin is that I'd need to start with a longer piece of steel, because it would have to extend past the end of the block where I'd attach my indexing ring. A home-made holder would permit me to put the ring on the front. The ring only needs to be wide enough for a set screw.

It also isn't out of the question to clamp the ER block to a carrier (made out of softer material) that would have the requisite holes I need, and just live with the longer cutter (or shorten it before hardening it). Decisions, decisions...