Mystery collet block

[smfr]

I just got this off eBay. It was advertised as an MT2 hex collet block, but it certainly ain't MT2.



The bore is about 0.7" on one end, and 0.75" on the other, and it's about 3" long. It looks like the taper might stop in the middle, with the cylindrical section of the boring being 0.7" (kinda hard to tell from this shot):



The nut is certainly 3/8 16TPI, which does fit the MT2 collet story.

I've looked at the specs for Jarno and Brown & Sharpe tapers, but nothing seems to fit. Does anyone have any idea what this might be?

 

[miner49r]

This might sound like a dumb question. Did you try a MT2 collet in it?
Alan

 

[tel]

That would be my question as well.

 

[smfr]

Heh, I did ;D I also tried some MT2 arbors.

Anything MT2 falls right into the wide end. On the narrow end they stop at about the right spot, but I can still wobble the arbor around so the taper isn't right.

 

[rklopp]

Brown & Sharpe #7 taper is close to MT2.