Step Motor DC Power Supply

[BobWarfield]

Transformer: Toroid from Parts Express with a 56V secondary (among several others). $29.95

Ajax CNC Rectifier Board: $29, has inrush protection.

Electrolytic Capacitor: eBay, about $3.

Specs: about 72V DC @ 5A out. 72V is about right for Geckos, just a little margin for error from their 80V rating.

This about twice the amperage needed for my 2 little steppers based on the design work I did, which suits me fine. The chassis and mountings consist of a piece of 18 gauge steel, a pipe clamp, and an expander rubber pipe plug from the hardware store. Miscellaneous parts and hardware probably cost me in the neighborhood of $15, so the total power supply cost came in at about $80.

That Ajax board made it an hour long project once I had all the parts. Really nice!

If you want more detail, try:

http://www.thewarfields.com/MT/MTLatheCNCDrivers.htm

Last weekend I finished up the rack mount PC for the project:



The 'puter is way more powerful than Mach 3 needs with an Athlon 64, but only cost me about $340 with all new components. Details available here:

http://www.thewarfields.com/MT/MTLatheCNCPC.htm

Next step is to put together a sub chassis with all the relays, fusing, and ancillary circuitry, then after that I need to wire up the GRex. All of that plus the power supply will go into a second rack mount chassis.

I might finish this thing yet!

Whoops! Getting over optimistic again.

Best,

BW

[Adobe Machine]

Bob, looks super..and your website is "top notch". Looking at your control panel just makes me drool...um, might really rethink my panel.

What is your thoughts on using a laptop to control my lathe retrofit ?
My computor guy says should be no problem and suggestions from swoolhead indicate I should be good to go..Would like to use it, will fit the concept .

Thanks

Adobe ( old as dirt)

[BobWarfield]

The biggest objection I've heard to laptops is they're sometimes incompatible with parallel breakout boards. Either the voltage is wrong, or they may not even have a parallel port. If you used a GRex, that problem goes away.

However, you need to be aware that the GRex is not ready for prime time on lathes. Until we get a firmware update, it will not be possible to thread. I'm sticking to it, just because my panel needs all the I/O, but it's something others may not be so patient with.

Best,

BW

[Adobe Machine]

Thanks for your reply Bob..I'm using Desk CNC and have a threading program developed by Fred Smith @ imserv. really works good, but requires a spindle encoder.I tested the program ( my lathe retro fit is not finished yet ) on a friends turning center..thumbs up..in fact he was a little bummed out as he had purchased a real expensive lathe program for that purpose. Due to a bad wreck 4 yrs ago, I can not stand and monitor a manual lathe threading for very long,so my decision to retro fit a 50 yr old lathe ( I have owned since new) was pretty easy...

I'm now redrawing my control panel (palagerism ) really like yours as I said..

Adobe (old as dirt )

[NC Cams]

I ran into the infamous parallep port "issue" on my laptop recently as well.

I have 2 hardlocks that I need to run some special software. I have them "piggybacked" on my desktop and they read thru each other just fine and also run the printer.

Installed one on my laptop and it worked fine. Then I added the second dongle, neither one worked. Moreover, the floppy disk quit working because it also uses LPT port to run.

So to do anything with my laptop, I have to run either one or the other but never more than one at a time. This is a real PITA when you have to use the two programs that use the hardlocks simultaneously.

If you make/create your own 'break out board' (BOB), you should be able to configure one so that the IO's run via low voltage/current optoisolator chips. Thus, the low voltage issue shouldn't bother you much anymore.

However, the use or a traditional desktop might be less problematic all things considered. Life is too short for some problems.

[Adobe Machine]

Thank you very much for your reply,I think I understand what you are saying ( I'm a real computaor klutz, just some thing will not go through my thick head ) Now another question: With Desk CNC, it goes from the printer port to the "Motion Control Card", then to The servo amps...what function would a breakout board do in this type of system.?.know that sounds real newbee,I just do not know .

Adobe (old as dirt)

[BobWarfield]

The "Motion Control Card" is the breakout board. The DeskCNC board probably does more than a basic breakout card, but I believe most of those functions are available via Mach 3 + a regular breakout card. You'd have to check into it more deeply to be sure.

Lots of newer breakout cards out there, and the old ones have been revised as well. You will know the old standbys, here are some of the newer offerings:

http://www.candcnc.com/ is a new firm by the guy that designed the most popular board that many sell.

http://www.pmdx.com/ PMDX has a slick looking line of products.

http://www.cnc4pc.com/index.htm has a pretty new board that I've heard good things about.

Best,

BW

[alnicov]

I can vouch for the PMDX 121, which incidentally is upgraded to the 122 now. Been using it with Mach3 for over a year and have not had any problems at all. Easy to install too.

[Adobe Machine]

Thanks very much Bob, I just was not sure if the terms were the same or almost the same or if a breakout board was a seperate item. I converted my Tree Mill a couple of months ago, using pieces supplied by Machine Tool Camp and imserv., using the Desk CNC system..Real pleased how it works. I just do not have the electrical back ground to design a system ( I'm a M.E., and still use my stick, er, slide rule to solve mech. problems)I just picked up a smattering of electrical in school. That means I'm be-holdin to you E.E's., and computor science guys,so I bought the system with a complete wiring diagram and enough explination for dummy's like me...Thats why I'm using the same system on my Lathe conversion, as I'm some what comfortable with it, and I fumbled around enough learning the electricals on my mill. Thats what happens when you get old,can only do one thing at a time.( Plus my wife says I'm still stuck in the '50 s)... any way, thanks..

Adobe (old as dirt)

[BobWarfield]

The beautiful thing about using the same system again is if something isn't working, you can swap back and forth to find out where the problem is.

BTW, that's what most of the "experts" try first anyway!

Best,

BW