On Monday, November 4, 2013 8:38:21 PM UTC-8, DoN. Nichols wrote:


It
runs from a 6502 (what was used in the Apple ][ and the Commodore Pet
among other home computers. In particular, while it has Carbide inserts
for many things including threading, it is necessary to slow the spindle
speed down to about 200 RPM or lower for moderately coarse threading such
as 20 TPI or 1 mm pitch. Leave the spindle speed faster, and it
displays an error message on the CRT (if present -- that is an option),
and some error number on the LED readout display. Turn down the
spindle speed, and it starts threading. The spindle has an index plate
to show it where it is in its rotation, and the lathe has to compute
at which index hole it makes its next step. (And, it does everything
internally in metric units, though it will accept commands in inch
units. And it is a little more precise in metric units. Steps of
0.01mm or 0.002" and when stepping manually in inch mode. sometimes it
is two ticks before the next figure displays, sometimes one.

Don:

Since it cuts better in metric... have you tried to cut inch threads in their metric equivalent? Like 20 Threads Per Inch = an inch pitch of .050 OR a metric pitch of 1.27mm.

Here's a site with a list of pitch conversions to metric.

http://www.newmantools.com/tech/pitchconversions.htm


And the program format is insanely picky. Decimal point
location is implied, not displayed. and if you lose a space out of a
line of code, everything is multipled by 10 because of the position.
Here is what the start of a program looks like:

Heh, yeah. If memory serves, that's the old NC "Full Address" format. Sometimes they had following zero suppression, and sometimes leading zero suppression. Just be glad you don't have to use a Flexiwriter and punch your programs out on paper tape and THEN take the tape over to your machine and feed it into your tape reader. Ahh the good ol' days... Just kidding, those days were miserable compared to modern machines and CAM systems that do all the grunt work for you.



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BottleBob
http://home.earthlink.net/~bottlbob

#92
Ways to machine?
Some are obscene
Many are routine
A few seem from the Pleistocene