Re: Ini file

["Peter Cook" <kf2qd-at-terraworld.net>]

Double check the feedback - late 60's early 70's has a high likelyhood of
using resolvers(analog sine-cosine ) - would have to add encoders. If it is
so accurate and in such good shape wold they even let yu near it? Nothing
personal but most places I have worked would leave such a machine alone
because they don't usually want to fix something that ain't broke.

Pete

>
> So I have a question for those on the group..
>
> I am working for a company that has a lot of gooood iron..  Some old
> equipment but very very good machinery.  One that peaks my curiosity is a
> Moore Jig borer that is unlike others that I have seen.  It had a servo or
> stepper drive type of system on it.  Very old.  The machine as I have been
> told is the most accurate piece in the precision room cause it hasn't been
> worn out.  I am not sure how old the drive system is.  My guess is late
> 60's.  Do you think it would be possible to scab into the drive and run
the
> motors with EMC.  I am pretty sure it has encoder feedback and am very
> curious.  The console on this bugger has round punch keys reminiscent of a
> 1955 typewriter with what looks like record and store type of
> programmabilty.  Any guess what I would need to check into to see if I
could
> run the motors????  The machine has been in a controlled jig bore room for
> years.  Perfect temp and humidity.  It has me warm and fuzzy...
>
> Mike Warehime
>
> -----Original Message-----
> From: emc-at-nist.gov [emc-at-nist.gov]On Behalf Of Dean L. Hedin
> Sent: Tuesday, April 02, 2002 9:48 PM
> To: Multiple recipients of list
> Subject: Re: Ini file
>
>
>
> > and restricting z axis acceleration orspeed does not help?
>
> The only problem with that is sometimes I would like the Z to move
> quickly!
>
> The problem only seems to occur when I am moving at the fastest feedrate
> (F7.0 units inchs) and more than one axis is involved.
>
> Also keep in mind that this is in gcode produced by my emcprobe program
> and consist only of a series G01 X Y Z movements.  on a 1/20in.  XY grid.
> As it is moving along it suddenly hits a point where the Z drops quickly.
> and this is the time that I loose Z steps.
>
> So what I've done in the filter program is to watch the delta z between
two
> succesive points and insert a feedrate command to slow it down.  I've set
> it up to apply a different feedrate for various ranges in delta Z so that
> I don't end up jumping drastically from one feedrate to another.  For the
> time
> being this has resolved the issue at hand.
>
> I should also mention that I am running NEMA34 motors 1.4 AMP 5V rated
> and I am not running them above rated voltage.  I have'nt improved my
driver
> board yet!  I don't think this is an issue because the problem occurs even
> on
> dry runs with no workpiece in place.  As configured the motors have
> sufficient speed and torque for the task at hand.
>
> I will fiddle with acceleration values to see if that helps.
>
> > > perhaps if you have a shared power supply, it has insufficient reserve
> > > power to move all the axis at once ? You could use more/bigger supply
> > > capacitors or
> >
> > unlikely with stepper motors.  the current they draw goes down a touch
> > when they are moving.
> > john
>
> Concur,  When I initially encountered this I added a large electrolytic to
> the
> motor supply.  Did'nt help.   Supply looks good on the scope.
>
>
>