Re: Heck of a time tuning servo motors.

Success!

So much for going to work today. Well if an independant contractor
can't play hookie, who can?

The problem was a combination of absolutely everything everyone
said! I needed some tweaking of the PD parameters on my servos. My
Gibs were definitely too tight (I think this was the biggest
problem). There is now measurable rocking of the carriage (less that
a thou at the edge of the carriage), but I'm sure with some tweaking
I ought to be able to get a good compromise.

I even got the Z-axis working. I saw Tim's post on the shoptask user
group about how to help minimize lash on the quill before. I have
yet to implement those operations, but it is on the list. I ran the
z manually with quite a bit of drag on the quill feed. This cut down
on a sort of bouncing of the head. If I was feeding down there would
be pressure as it first cut, but then it would feed itself into the
part and kind of chatter. This only affected plunging as I would
lock the quill when cutting sidewards.

I went with 7Amp slow blows on the fuses and these aren't blowing
now. It will occasionally peak higher than this, but that's what the
slow blows are for. By my calculations I should be ok as long as I
take it easy on doing rapids with all three axese.

Thanks for all the help!

My X axis now traverses so fast it threw the taper pin that holds the
handwheel on it half way across the room! I have since slowed my
rapids a bit because there just isn't that much traverse anyways. An
inch per second has the handwheel spinning so fast you can barely see
it.

-Erik Reikes