On Thu, 28 May 2015 06:43:51 -0400, "Jim Wilkins"
wrote:


rgentryatozdotnet

Is the feed screw Acme?

Does not appear to be. The thread _is_ 16TPI and fits a standard
'v'
gage nice and tight except for the points which seem to be just
slightly flatter than standard.

As a side note. . The threads appeared to be buttress style. . . .
untill I hit them with a toothbrush and cleaned off the oil. grin

Bob
rgentryatozdotnet

Then the screw and dial may be a repair, used to avoid buying an Acme
tap. I did that on my worn surface grinder with 3/4-10 threaded rod.
It isn't difficult to engrave a custom dial with a rotary index, using
a spreadsheet to calculate the turns. Were the numbers hand-stamped?

If the numbers are hand stamped (and I don't think they are) sombody
did a _VERY_ nice job of stamping.

I think both the down feed and the table cross feed are both 'V'
thread. Both fit the 'V' thread gage very well and the form just
isn't Acme.

I have the feeling that to keep the orig. cost down 'V' threads were
acceptable. Also makes it easier to fix if they ever go bad grin.

Bob
rgentryatozdotnet