Allen Bradley Help for new guy

[kroberts]

I have built a solid small 3 axis mill. It's all homemade but is constructed from Aluminum with linear bearings on all axis. Now that I have the basic design built I am ready to hook it up to a computer. I am a computer guy by trade was am a converted tool/die maker who is responsible for the maintance of CNC equipment up to 6 axis. I need to get a much better insight on how they work, so I thought this would be a great and useful project to learn on and a tool I can use often. I work on classic cars in my spare (right) time and plan on using this to machine aluminum parts. What program is most of you using to control servo's. I am using Allen Bradley N-2304-1 motors (x3) with matching Allen Bradley drives. I also have a Yaskawa SGM-04U motor with matching drive as the spindle motor. I can hook the motors to the drives and have all axis working smoothly. Everything is super tight and works great in testing. Acme threaded rods are the lead screws. Where can I find more info on actually connecting it to the PC. I thought about running each encoder to it's on serial port (4 is not a problem), do I need limit switches to find home? I'm sorry for the length of my first post, but I feel very luckly to have found such a great resource. I have used forums in my older cars (mostly my 66 mustang) and these are great. I'm going to try to post pics in my photo gallery.

Thanks in advance

[MetLHead]

How are you running the servos now? Did you test them with a battery box? Most of the DIY PC based control software available will output step / directions signals but not analog +/- 10v signals. If this is what you have then you will need some sort of additional hardware to provide the analog signals and receive the encoder signals for the drives.

Regards,
Scott

[Evodyne]

MetLHead is right-you'll need a board to convert step and direction pulses (the output of most common software) to +/- 10 volts. Rutex makes such a device. See the attached .pdf file. You'll also want a breakout box-basically a PC I/O interface that the CNC software can talk to. You hook your limit switches (yes, you can have a "home" limit as well as overtravel limits) into the breakout box. You can also use outputs on the breakous box to control things like spindle on/off and coolant pumping on/off. Many vendors sell these boxes. Hope this gets you pointed the right way. Good luck.

Evodyne

[kroberts]

Thanks for the help already. I was talking with another guy at work who has tinkered much more with CNC. He has a Douloi Automation MSB-4V Motion Server Block 4 Servo unit he said would make it easier. Now I am really lost. I will check on the pdf, it looks interesting. Photos are on the way, I just have to reduce the size to under the 100k limit.

Thanks again

[HillBilly]

I have seen the Douloi used in dedicated machines ( Software taylored to the application.) but did not know they had CNC interface software.

Darek

[kroberts]

Just got the pics uploaded.