Messages

21

General Mach Discussion / Re: 0-10 volt output for vfd

« on: April 23, 2009, 01:47:00 PM »

Well I replaced the motherboard with a new one ,same as my other machines.Same thing.
Any way to "smooth out" the 0-10 vdc signal between the bob and the vfd?

22

General Mach Discussion / Re: 0-10 volt output for vfd

« on: April 11, 2009, 02:14:49 PM »

looks like Jeff maybe right.I tried lowering the speed way down on another machine
and no pulsing.I'm at .5-.8 hz.I'll order a new motherboard and go from there.

23

General Mach Discussion / Re: 0-10 volt output for vfd

« on: April 11, 2009, 11:11:14 AM »

I tried adjusting the accel on the vfd.no real change.I'm using a smooth stepper.
The signal wire from the bob to the vfd is only about 12" and is shielded and grounded at one end.
I have a couple of other machines with Mach control so I'll see what happens if I lower there speed
real low.This may point to the pc.

24

General Mach Discussion / 0-10 volt output for vfd

« on: April 10, 2009, 05:53:00 PM »

Has any one checked the 0-10 volt signal output from a breakout board that has a speed control
for controlling a vfd?I checked mine and the output bounces around .It will change from say .105-.115.
This may not sound like much but at very slow speed it causes the spindle to pulse.At higher speeds it causes the gears to chatter.
This goes away at about 1 volt but at this point it is friction in the system , the voltage still bounces around.
Is this normal or can I have something set wrong?

25

General Mach Discussion / Re: Problems threading on the lathe

« on: March 25, 2009, 11:03:59 PM »

Yes I don't want to hijack this thread only a passing comment.This
has been one of the more interesting problems and I'm sure more to come.

26

General Mach Discussion / Re: Problems threading on the lathe

« on: March 25, 2009, 09:29:06 PM »

tested the fix today.I had increased my hp on the lathe before and this made it possible to thread.
I backed off on the torque and no problem.The random x move is gone.I tried a 3/4  x 8 tpi
at 600 rpm and worked fine.I jammed a 2x4 under the spindle and slowed it down 50% and still ok.
good work on the fix!
Now I have another trying problem,getting my spindle to stop with the same orientation every time?

27

General Mach Discussion / Re: Problems threading on the lathe

« on: March 16, 2009, 09:20:38 PM »

yes

28

General Mach Discussion / Re: Problems threading on the lathe

« on: March 16, 2009, 07:59:36 PM »

Smooth stepper test.I have had this issue with pp and ss.
With alot of effort I managed to slow my spindle and I get the error
with cv and no cv.I tried a g78 and a G32.same issue.I am free tonight to run
tests if any one needes a hand

29

General Mach Discussion / Re: What is your trade?

« on: March 01, 2009, 11:51:47 AM »

I agree.The first 9 months of my existance where pretty dreary indeed but once I
saw the light and found a cresent wrench 

30

General Mach Discussion / Re: Problems threading on the lathe

« on: February 28, 2009, 02:26:09 PM »

I had the same problem.I had it with p/p and s/s.
I had it with a g76 and g32.The only way to make it go away was to add a dwell
at the begining of each cut or increase the power to the spindle.I think as I said before
that the reference pulse is the critical thing here.Depth of cut is not the only thing that can
slow down the spindle, friction of the tool rubbing on the sides of the tread. This does not explain the random
x movement but with enough torque it seems to not start.Any one can simulate this problem by
-running the treading wizard and generate some code.
-don't load a tool or work just turn on machine and cut some air
-apply a load to the spindle ,I just lever a 2x4 up against it until a rpm change is detected
-do this while threading in air.
Watch the x axis go into stupid mode.