Messages

341

General Mach Discussion / Re: Has anyone used Viper Servo drivers?

« on: June 05, 2009, 02:01:33 PM »

Agreed:

1) 80Volt Limit.  This alone makes it harder to find a transformer that is just less than 2:1 when making a DC Power Supply.

2) Fault limit of 147 (I thought it was 128) that is not scalable.  This is a real pain when you use the pulse multiplier feature because the fault limit does not scale with multiplier, to get things to move without faulting your acceleration / deceleration profiles have to be slow (ie: takes longer to reach the MAX IPM during rapids)

Thanks for the info

342

General Mach Discussion / Re: Has anyone used Viper Servo drivers?

« on: June 04, 2009, 04:44:37 PM »

What don't you like about the Geckos ?

343

General Mach Discussion / Re: Constant Lathe Spindle surface feed

« on: April 21, 2009, 09:59:26 AM »

Thanks HOOD !

344

General Mach Discussion / Constant Lathe Spindle surface feed

« on: April 20, 2009, 06:09:57 PM »

I have an 80's Mori Seiki SL-1 that I am planning on converting to MACH3.  Can Mach3 addjust the Spindle Speeds to provide a constant surface feed rate as the diameter changes ?

Thanks,
Joel

345

General Mach Discussion / Re: Quadrature Divider Circuit vs G902 Pulse Multiplier

« on: February 24, 2009, 10:33:13 AM »

Tony,

Thanks for the responce.  Good point about "The only thing I would say is that it will make the motors noisey on stand still as they will have further to "hunt""

Did you build a circuit like one of these, or something else ? 

Also, my current resolution is .000025in/pulse.  So a 4:1 circuit would put it at .0001in/pulse, which is still better than the machine was built to back 1986 (.00013in/pulse)

All thought and comments are welcome, the design phase is sometimes the best part....

Thanks,
Joel

346

General Mach Discussion / Quadrature Divider Circuit vs G902 Pulse Multiplier

« on: February 23, 2009, 11:54:46 AM »

Has anyone used a Quadrature Divider Circuit instead of a G902 Pulse Multiplier ?

The Problem:  1000 line Quadrature Encoder ( 4000 pulses per rev ), 2:1 on the motor pulley, then 5 turns per inch on the lead screw = 40,000 pulses per inch or .000025 inches per pules.

I do not need that kind of granularity and the MAX speed is 100IPM.  So I tried G902 Pulse Multiplier set at the 1:2, works ok.  I now get up 200IPM but the acceleration must be set very slow to keep the G320 from Faulting.  This make since as the G320 will fault after +/- 128 counts of position error and by adding the G902 set to 1:2, I have just cut this in half to 64 counts.  I am also concerned with steps loss after reading the post below:

http://www.machsupport.com/forum/index.php/topic,2749.msg21457.html#msg21457

Possible Solution:  Quadrature Divider Circuit of 2:1 or 4:1.  Would this allow for both faster IPM and Faster Acceleration ?  Has anyone built one and tested it ?  I found these circuits on the Gecko Yahoo Forum, however I can not find any real data of success or failure using something like it.





Thanks,
Joel

347

General Mach Discussion / Re: Homing Order?

« on: August 15, 2008, 05:21:28 PM »

Twins ?  I'll take them home.  Looks great !

348

General Mach Discussion / Re: Bridgeport Discovery 308 retrofit

« on: July 24, 2008, 12:05:12 PM »

I am also interested on how things will work out with your 308s.  We plan to retrofit this BP 412 with Mach3 also

349

General Mach Discussion / Re: Cutting Circle / Hole

« on: March 07, 2008, 10:02:22 AM »

If the problem was at the 12:00 or 6:00 positions, then check your Y Axis backlash.  If it was a the 9:00 or 3:00 poistion, then check you X Axis backlash.

350

General Mach Discussion / Work Offset Code Generator

« on: March 05, 2008, 03:08:13 PM »

I have been using work offsets to help me when using multiple vises.  This works great in Mach3 and with subprograms its even greater.

The downside is that if I need to change tools say 5 times on the part, then each vise or work offset that I use is 5 more of the same tools changes. (3 work offsets is 15 tool changes)   I wanted a way to change the tool, then work that tool on each of the offsets before going onto the tool change (3 work offsets and only 5 tool changes just like in the original NC program)

So I have created a simple tool that reads in a NC file and looks for tool changes, then inserts the work offset G Codes for each tool.   This keeps tools changes to the same number as before while working each of the desired work offsets.



This is also handy when you have a NC file today, but tomorrow you want to use 2 or 3 vises for the same part.

Its not perfect, but it works.  I have attached all the Visual C++ project files needed if you want download and build/modify it to your needs.  Or you can try the EXE file.

Thanks,
JH