On Mon, 04 Oct 2010 22:34:56 -0400, "Michael A. Terrell"
wrote:


Gerald Miller wrote:

On Mon, 04 Oct 2010 13:42:43 -0400, Brian Lawson
wrote:

On Mon, 04 Oct 2010 11:58:39 -0400, Bob Engelhardt
wrote:

I got a Dumore "precision" drill press at the dump, but it's missing the
key for the Cushman chuck. I found a Jacob's chuck with matching
specs & I can get a chuck for it that should fit my Cushman. But, just
to be sure, I'd like to check that the tooth pitch matches.

Does any one have a Model 0 Jacob's chuck that they can look at for me?
I need the number of teeth on the sleeve. The Model 0 is the smallest
Jacob's makes: 0-5/32 (4 mm) capacity. The sleeve is .85" diam.

Thanks,
Bob


Hey Bob,

Got one on a "sensitive drill press" gadget.

Both Chuck and Key here are Jacobs No. 0 and chuck is also stamped as
having 0 Taper (for mounting I assume)

Chuck has 23 teeth, Jacobs KEY 0 has 11 teeth. Gives a ratio of 2:1
turns of the key to one turn of the sleeve.

Key guide pin diameter is .153 long and .1235 diameter (I will get out
the pin gauges and check the chuck holes if you want, but I assume
they are 1/8")

Key main shaft with cross-lever is .35 diameter by approx. .83 from
top the top of the teeth, and 1.21 overall top to tip.

Major diameter of Key "barrel" just above teeth is approx. .440
Not real sure how to measure easily, but across one tooth and one land
at the minor diameter I get approx. .334

If this isn't enough, grime a shout and I'll dig deeper, but I note
that KBC Tools

http://www.kbctools.com/can/main.cfm

has

SKU # 1-508-03505 JACOBS K0 CHUCK KEYS $4.75

That may be a Canadian site and price, but if you are in the USA, try
typing www.kbctools.com and get the correct US site.

You saved me a trip downstairs to measure mine.


You leave yours laying around?
In the shop.
Gerry :-)}
London, Canada