Dyna Myte 2400 milling machine retrofit

More
28 Feb 2015 00:35 #56340 by muzzy101
I have a rather general question about retrofitting a Dyna Myte 2400 tabletop milling machine. I'm a student in an engineering automation class that is working on this project and I am not very knowledgeable about this entire process but I am learning. We have purchased a Gecko G540 stepper motor drive, a mesa 6I25 Mother card, and a mesa 7I76 daughter card to communicate with the existing stepper motors for axis control and to hopefully control the spindle. Is this hardware configuration correct and what should our next step in the process be?

Please Log in or Create an account to join the conversation.

More
01 Mar 2015 01:48 #56360 by cmorley
This seems correct.
Now you must configure linuxcnc to the specifics of the hardware.
You can try pncconf but you won't find the 6i25 on it. you can use the 5i25 then after change all '5i25' text with 6i25 in the HAL files.

or you can start with a sample hm2-stepper config (you will have to supstitude names with it too)

Chris M
The following user(s) said Thank You: muzzy101

Please Log in or Create an account to join the conversation.

More
22 Apr 2015 07:28 #57987 by muzzy101
Thank you for the input! I have been successful with the hardware I mentioned. I can control x, y, and z. The problem is in controlling the spindle. I haven't gotten very far yet, but we have attempted to use the existing spindle controller and it's power supply. I'm sending the signal input from the Mesa 7I76 card using the TB-4 spindle outputs. While attempting to create a configuration for linuxCNC, I can control the stepper motors for each axis in test mode, but I have not been able to activate the spindle. Is this method sound or should we control the spindle another way?

Please Log in or Create an account to join the conversation.

More
22 Apr 2015 20:55 #58006 by andypugh

Is this method sound or should we control the spindle another way?


That rather depends on what sort of spindle it is, and what signals the spindle drive expects.
Is it an AC motor driven by an inverter / VFD?

Incidentally, you can connect the G540 directly to a 6i25 if you have the G540-specific firmware. But that won't give you very much IO or the spindle control / encoder.
The following user(s) said Thank You: muzzy101

Please Log in or Create an account to join the conversation.

More
03 May 2015 10:47 #58346 by muzzy101
Our semester is almost over and we have decided to put the spindle on a switch with the existing pot for now. We will be tackling that problem next semester. I have a completed configuration that will allow me to execute a program. However, the step per inch required to set the resolution on our step motors is 101600. I can jog the motors, but when I attempt to run a program, I get this alarm:

hm2/hm2_5i25.0: stepgen.00.maxvel is too big for current step timings & position-scale, clipping to max possible

I get that alarm on all three axis. We are using the mesa 6i25-7i76 combination (but the firmware for a 5i25-7i76) with a Geco G540 driver. Attached are the data for our step motors. On the spec sheet, the -0.7 motor is the motor we are using. It is wired to the gecko in parallel. The excel spreadsheet attached includes other pertinent data on our mill. What is my next step?
Attachments:

Please Log in or Create an account to join the conversation.

More
03 May 2015 10:50 #58347 by muzzy101
Here is the spread sheet. I don't think it attached to my previous message.

Please Log in or Create an account to join the conversation.

More
03 May 2015 10:56 #58348 by muzzy101
Here is the spreadsheet I tried to attach in .pdf format. Maybe this will work.
Attachments:

Please Log in or Create an account to join the conversation.

More
03 May 2015 21:10 - 03 May 2015 21:11 #58351 by PCW
Can you post your hal and ini files?

The error is probably just what it says, that is your step timing (step length and step space)
will not let you reach the maximum velocity that you have specified in your .ini file (with MAX_VELOCITY)

The maximum reachable velocity in machine units per second will be:

1/ OUTPUT_SCALE *(steplength + stepspace)

In addition the stepgenerator needs some "headroom" so the stepgenerator
maximum velocity (STEPGEN_MAX_VEL in the .ini file) should be about 20 %
greater than the MAX_VELOCITY parameter for each axis (and it must be reachable with the step timings)


So for example if your step timings were specified at 3000 for step time and
5000 for step space (3 usec and 5 usec), the maximum step generator velocity would be
1/101600*8e-6 or ~1.23 IPS. The maximum velocity should be about 20% less than
this so MAX_VELOCITY in the .ini file would be about 1 IPS.
Last edit: 03 May 2015 21:11 by PCW.
The following user(s) said Thank You: muzzy101

Please Log in or Create an account to join the conversation.

More
03 May 2015 22:35 #58353 by muzzy101
I haven't accessed the hal of ini files yet. We've been working with the mesa configuration wizard. I will have to figure out how to access those files and i will post them as soon as I can get back into the lab. I'll investigate my settings as well and do the calculations that you have suggested. Where should I look for those files? Bear with me as I have a lot still to learn about this system.

Please Log in or Create an account to join the conversation.

More
04 May 2015 00:00 #58356 by PCW
The configuration files will be in your home_directory/linuxcnc/configs

from a terminal typing:
cd ~/linuxcnc/configs
and then
ls
should list them

If you created them with pncconf, they may be in
your_home_directory/linuxcnc/configs/my-mill
or
your_home_directory/linuxcnc/configs/my-lathe
or
your_home_directory/linuxcnc/configs/my-LinuxCNC machine
The following user(s) said Thank You: muzzy101

Please Log in or Create an account to join the conversation.

Time to create page: 0.251 seconds
Powered by Kunena Forum