I was wondering if anybody could tell me if it would be a problem to house all of the electronics for a CNC conversion inside the same electrical box as a computer. I am hoping to put the computer in the box to keep from having 2 box's(A computer and a large electrical panel). Will there be interference problems? -Adam

I did it with no problems with different drives. Just use shielded wire and have enough air flowing through to keep things cool.

Will there be noise problems is always a gamble. Do what you can to avoid those to start with and your chances of trouble decreases.

I agree with LeeWay, use schielded wire, keep the big voltage/power wires as far away from any logic level wires, as you can, cooling fan is good, etc..

One thing to think about, and this comes from my 15-20 years of retrofit experiance, is, when a computer is attached to a milling machine, will the hard drive in the computer last? Today, anytime i mount a computer to a machine, it has all flash memory, no hard drive. There is small vibrations in the mill that will kill a hard drive. The faster you run the spindle, the faster the hard drive will crash. I did some tests on a bedmill, (20"x40" travel, not a tabletop mill) with a 3 HP, 15,000 rpm spindle. You couldn't feel any vibration in the machine, but the hard drive would only last 1-2 hours! No kidding! i couldn't believe that so i went and got more hard drives, and burned them all up! I also noticed that the guys that never ran the spindles over about 1200 rpm's, their hard drives lasted for years, and the guys that cut molds, with 3-5,000 RPMS, would burn out the hard drive in a year or so. Flash memory solved that problem!

I even use shielded wire between the breakout board and the Drive, for the step and direction signals. Remember to only attach the shielding to ground on one end of the cable, NOT BOTH ENDS.

If you havn't bought a break out board yet, check out Bob Campbells (Campbell Design). I think his instructions are poor, written for an electrical engineer, not a tool maker, BUT, Bob will help you if you have questions, AND the biggie: if you don't understand electrical noise, Bobs board is the best you can buy, that i have seen so far, for a few reasons that someone like you don't need to spend time learning about. example: you cant run logic level voltage through the limit switches for 2 reasons, one is you will be peppered with faulse limit switch tripping, the contacts in limit switches are way to big for logic level signals, and the second is, without the optical isolation, the limit switch wires would be an electrical noise highway right into the computer, creating problems that a novice cnc builder don't need to deal with. Bob has taken care of all that, in his breakout board.

Good Luck

I was wondering if anybody could tell me if it would be a problem to house all of the electronics for a CNC conversion inside the same electrical box as a computer. I am hoping to put the computer in the box to keep from having 2 box's(A computer and a large electrical panel). Will there be interference problems? -Adam

Sounds like a plan to me. Especially since you can get those old large boxes super cheap at thrift stores. Put it on a nice stand and you have a good base to mount your monitor and mouse.

[QUOTE=springlakecnc;470623]

One thing to think about, and this comes from my 15-20 years of retrofit experiance, is, when a computer is attached to a milling machine, will the hard drive in the computer last? Today, anytime i mount a computer to a machine, it has all flash memory, no hard drive. There is small vibrations in the mill that will kill a hard drive. The faster you run the spindle, the faster the hard drive will crash.

So would placing the computer on a separate table be a good solution?

Thats what I do. My enclosure is mounting on a table and my "desk" is right next too the machine, computer, electrical enclosure...I built a window into my enclosure so i can everything.


-Jason

Yes, putting the computer on a table, or anywhere that is not attached directly to the machine will save your hard drive from early death!

My computer, hard drive, CDROM, G203V's, linear power supply and X3 motor driver are all mounted in an electrical controls enclosure (nice big beefy son of a gun) and it is mounted to the wall with wiring to connect to the axis motors and spindle and other controls. Provide plenty of cooling if your driver heatsink(s) are enclosed and you should be fine. Isolation of signal vs power vs low level vs high is a must. Shielded wire is best and as stated earlier - only ground one end of the shield on a shielded cable.

You can see my layout in the gallery on my website.