On Tue, 9 Dec 2008 20:38:54 -0800 (PST),
wrote:

On Dec 9, 8:02*pm, Bob Engelhardt wrote:
A little while ago I inquired here about an SPI keyless chuck. *Comments
were favorable & I bought one.

I just got around to checking it with a dial indicator & I'm really
impressed. *I put the SPI chuck (Swiss brand, but made in Taiwan) on the
Enco (Phase II) arbor (made in China) & mounted them on my HSM Delta
drill press (made in Taiwan). *My indicator reads to .001, so I can't be
sure what the TIR is precisely - cause it's less than .001. *Probably .0005!

Bob

Concentricity is important, but just as important is a chuck's ability
to hold a tool under heavy load. I find that's what seperates them the
most.

You should stick a 1/2" drill in the chuck and put it through some
mild steel. Lean on the feed handle (hard!) and see if the bit slips.
Run a gun tap into some steel (3/8" NC and larger) and see if the
chuck holds.

Regards,

Robin


Good luck getting that gun tap back out though.. most keyless chucks
dont reverse worth a ****

Gunner