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1

SmoothStepper USB / Lathe build now with a Smooth Stepper Maybe ???

« on: March 30, 2009, 08:35:01 PM »

I have converted a small 8x12 lathe by adding steppers with G202's and new ball screws on the X and Y.The spindle has a  Nema 34 DC Brushed Servo from HomeShopCNC with a G320.
Bob Campbell breakout board and a Sound Logic Encoder board. E2 500 count encoders on all axis including the steppers. Differential converters on the encoder lines to keep noise down.
I need the spindle to act as a lathe spindle sometimes and as a rotary axis other times. Now with a parallel port the spindle is limited to 650 rpm at 43khz. I think the 4mhz that a SS produces would be what I need.  Need more speed. I was wondering are there any hang ups going with the SS on a lathe in this configuration?
I read the manual seems like it would be very easy to hook up. Plus I can use my existing boards.

I don't want to end up with another paper weight like the G100 and the license I bought for it.

Donny

2

General Mach Discussion / Lathe Servo Spindle settings question

« on: March 26, 2009, 08:18:30 PM »

I have converted a small 8x12 lathe by adding steppers with G202's and new ball screws on the X and Y.The spindle has a  Nema 34 DC Brushed Servo from HomeShopCNC with a G320.
Bob Campbell breakout board and a Sound Logic Encoder board. E2 500 count encoders on all axis. Differential converters on the encoder lines to keep noise down.
X and y work fine. C index's fine. 11.11111 Steps per gives me 360 deg's  on the DRO.  Seems that might be a bit low of a number but it seems to work.
Now I set up the Spindle as a spindle and I believe I need to change the Steps per. so that 1 number of the dro is a full 360. To get that I have a Steps per of 4000. Now I am running at 45khz and that gives me a max limit of 675 In's per Min. Somewhere I read that 50 In per min was 3000 rpm. I am just not getting close to that If I set my spindle speed to 1000 I only get around 75 rpm. Haven't broke out the tach yet to check but its way to slow.
On ports and pins there is 4 encoders settings. I assume that's X,Y,Z,A. I just put the pin numbers in for the C axis in the 4th slot. Now where do I put the encoder information for the spindle? I am not getting any spindle feedback on the screen.


While on the subject of encoders. Is there a lathe screen that has X,Z,C with a spot for encoder feedback. I found a Mill screen that has XYZA but I need this for the lathe.

I'm not using The Sound Logic Dll because its not working for me. Want to get these other things addressed first. One small step at a time to keep it simple.

I have went through the manual but have not found or if I did find understand the info about the above questions. I also searched the forum with little success.

Donny

3

General Mach Discussion / Servo with Gecko320 blowing fuses

« on: March 25, 2009, 10:19:49 AM »

I posted this on the yahoo group but yahoo is slow slow so I thought I would post it here. Hope no one minds.

Been a few years since I have done anything with CNC so I have to relearn it again.
Here is my setup. Lathe with steppers on X and Z. Servo on the A axis. All motors have 500 count US Digital E2 encoders.
Breakout board is Campbell on one Parallel port. On other pp is a Sound Logic Encoder board. All cables are hooked up per the two boards specs.Triple checked.
X and Z work fine. I get encoder feedback in Mach3. The plugin dll don't work but that's a problem for later. One thing at a time.
The servo worked once. I turned the limit up and grabbed the motor to see what kinda torque it had. Well it was strong until it blew a fuse. Now it blows fuses
anytime I jog.
Any ideas. My first foray into servos.

Donny