American Flyer wrote:

The problem with the Geckos only being rated for 80V is not so much that
we couldn't use full 300IPM speeds, it's that the power
supplies in our mills produced in excess of 100V. The Geckos can't
take this as an input which means we would have to come up with a
way to supply only ~70V at ~40-60A (at this point I'm assuming
that Paul's mill and mine have identical servo power supplies). The
motors are actually rated 92V.

The servo drivers on my mill are working fine, but are the old
original ones which PWM at about 5KHz. They squeal, and being 20
years old it is questionable how well they can be supported when
they eventually break. Regardless of which USB controller I end up
using (my own or the G2003), I think I'm going to put Rutex servo
drivers on my mill. Since they are rated at 200V, they will be in
no danger of damage from the 100V+ supply input, even if the power
company decides to send some bonus volts. The Rutex also have the
nice feature of being able to software adjust the PID settings
via an SPI port. With the right software, the PID alignment could be
completely automated.

By the way, I've been running my mill at 300IPM (no cutter)
to see what it's like. It's easy to envision major carnage if anything
goes wrong at that speed.

Harrison Young

Harrison, I have new servo amps from Servo Dynamics in Chatsworth CA.

Got everything working today except I have a continuous chatter or low

amplitude

oscillation in the x axis servo. What could be causing that?

Z and y axis are working fine as does the tool changer.

The knee goes up and down properly after I swapped one 3 phase wire.

Mark wrote:

If the stock PSU supplies over 100V, you have two options. The 200V Rutex
drivers at $220/axis, or a new PSU. The Rutex drives is probably the cheaper
route, with the advantage you pointed out.

Paul, lost in all this, why were you interested in a PC based controller? If
the Bandit works, why not just run it till it has failure which would cost
more than the PC controller retrofit. By that time you will have a much
better feel for what you are looking for and what is important.

Mark
www.wankel.org

I am just gathering info just in case.

Paul Lamar
 
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