Re: DON'T CUT THOSE WIRES !!

List

Sorry for the fragmented nature of this post my eudora seems to have died.
(This post! You say? Ray's are all fragmented.}

Andrew wrote

-----om-----
I looked into one of the motors, and was surprised to see only 4 contacts,
2 of which seemed to be the DC current + and - and 2 which came from a
gizmo on the back which I assume was the encoder. If the things have
tachometers they are must be someplace else- or can speed be calculated
from the encoder pulses?]
-----

Yes speed can be calculated from encoder pulses but my guess is that they
were not in 1983 when your machine was designed. My guess is that the wires
that you are seeing coming from a gizmo on the back of the motor are from a
tach. Most encoders have at least 6 to 8 wires to them. Resolvers have
six. You could disconnect a pair of these gizmo wires and put a dc volt
meter across them. Turn the motor a little and you should see a dc
voltage. Reverse the motor direction and the dc should change polarity.

Most likely the encoder or resolver is directly connected to the ball
screw. You may have to crawl under the thing or take off the covers on the
end of one axis.

-----om's-----
A while back I prototyped a cable and software
to run g code through the parallel port of a pc to a tape in on an old AB
7300 cnc. The cnc would accept all of the code that it needed and then
pause the parallel port.

[That sounds like a promising approach. Do you have any of these
cable/software kits you'd be willing to sell? I'd like to try this, if I
can coax my machine into booting up all the way. Currently it won't accept
any commands, although I can hear relays working- maybe replacing some (or
all) of them is called for.]
-----

If your machine comes out of the coma, I'll try to rustle up the stuff up
for you. One thing I do for controls that act like your's is to reseat all
of the computer boards. That is why I asked what computer it had in it.
With all power off, you should be able to pull each board out an inch or so
and then push then back firmly into the rack. This might cause problems
depending on how memory is set up and how you reboot the machine exec.

I saw on your post to Fred that you want to run an indexer rotation around
X. If you do not have this on the current machine that would be an
excellent reason to retrofit. An indexer that will step 1 degree will cost
much more than the hardware costs of a retrofit with emc.

Ray