CNC Circuit Boards for My CNC Router Table Mad Mod

[Bernd]

As I mentioned in my thread, CNC Router Table Mad Mod that I might make my own circuit boards for this project or at least make a prototype to try out the motors on the different axis's as I get them done. I may still decide to buy a whole package. It all depends on the out come of this trial.

I figure since I had the IC driver chips and the motor that somewere in a pile of papers I'd find some info on the boards. I found where I had orginally got the info. But as usall the site had disappeared. So I did some searching and finaly found it again. It's Aaron Bowser's site. He has downloadable circuit diagrams that can be used by the "toner transfer method". What I also found was several other ideas from different sites on using this particular chip. After looking at all the info I had I decided that I could come up with a board that incorporated all this info.

Now one word of warning. The UCN5804B is no longer made. I did find a place that you can purchase a simalar chip. Here's a place that you can buy the whole works from, StepGenie. The StepGenie is a 14 pin package, the UCN8504B is a 16 pin package.

Now, I did say I have programs to do the schematic layout and board design. That still left the making of the board. Since I had done this a while back, making my own boards, it's a rather messy project, plus you are working with a very highly corrosive liquid, sulfuric acid. Then I remember a freind of mine saying how he found a place on the interweb that you could down load software, the program contains both a schematic design and a circuit board design program. When your done with your design all you need to do is upload it to their site and for a fee you get your circuit boards in 2 to 3 days. So off I went on another surfing expedition and came across the ExpressPCB site. If your interested in this take a look and read how it's done. The software is free. I've already downloaded it and am playing with the software.

So as soon as I get something that's of interest electrically I'll post it in this thread.

Bernd

[Gadget]

Very interesting Bernd, I went the easy way and bought a driver and motor kit but I didn't know what I was doing so a kit was the easiest. Be sure to let us know how it turns out.
Dan

[Bernd]

I spent quite a few hours Sunday night surfing the interweb and reading about stepper motor driver chips. The one I have are no longer made, the Allegro UCN5804B. The closest chip is the “StepGenie” I mention in my original post. It’s not an exact duplicate. One of the differences between the two chips is that 8504 can only output 1.5 amps max at start up and has a continuous current rating of 1.25amps. This could be one reason why it’s no longer made. The “StepGenie’s” output can be connected to hexfets for higher amperage output, as high as 200amps. Also the 8504 is a 16 pin dip, were as the "StepGenie" is a 14 pin dip.

After all that research I’ve decided that it’s pointless to make my own boards for this project. I’m either going to buy a kit, since I like soldering my own boards, or buy a complete package. For now I’m going to hardwire a board so I can run the axis’ to just try them out.

I also studied the break out boards that are used to interface the computer and motor driver boards. I came across a web site in the UK that has some very interesting info. They added an opto-isolator chip. IIRC I haven’t come across any mention of opto-isolated break out boards that are available to the CNC router table hobbyist.

Here’s the web site: opto isolated break out board. Go down to the “schematic.gif” and click on that. You’ll get a schematic showing how to connect the parallel printer port to the break out board. So it looks like I’m going to go that route to make my break out board. I think this is a great idea since it isolates the computer mother board from the rest of the system.

What’s next? Well, I’m going to try and get all this info in one area so it’ll be easier to follow. In the mean time I need to work on designing the parts to hold the motors I have. I need to first figure out what NEMA size they are.

That’s it for now.

Bernd

[Bernd]

I've done more surfing and found that "some" of the commerical boards have opto isolated conections to the parallel printer port. So I stand corrected in my previous statement of saying that they weren't.

Bernd

[Gadget]

I bought a kit from Hobbycnc.com, it's optoisolated.

[Bernd]

I bought a kit from Hobbycnc.com, it's optoisolated.

HobbyCNC dosen't state in their write up as to using opto's. The Pro board has patented chip protection. I don't know what they mean by that. But if they do use opto's that's great. Like I said I've done a bit more surfing and found that some use it on their high end boards.

Bernd

[Gadget]

I'll double check my documentation. You are right, I don't see anything about isolation. Must have been the torch relay I was thinking about.

[Bernd]

Like I said I've come across board suppliers have different levels of boards they sell. For example CNC4PC has 14 break out boards. The higher end has optoisolated inputs from the computer printer port. Here's their web site: CNC4PC. Check out their 14 break out boards they sell.

Bernd

[Gadget]

Have you looked at candcnc.com They have a UBOB that looks like it will do a lot and is isolated. Here are the specs;

Single cable solution
8 High speed outputs for S&D .  8  Low speed  for general extrernal control.  Open collector buffered outputs for Up to 6 relays.
9 Fast Inputs for Homes, Limits, Probes, External sensors, etc.
Charge Pump output
Charge pump indicator
Plugs directly into our MTA100 for interface to various motor driver options.
Plugs directly into our new EZPlug250-5 card for up to 4 axis of tabletop stepper control
Plugs directly to our Table I/O card (see below)
Provides clean, buffered (full 5V TTL logic) signals for Step and Direction
Board mounted DB25 uses ONE standard M-F Computer cable
Board mounted serial port (DB9) for pass through communications to our other Smart cards
Expandable to use our low cost Port 2 card (Even MORE I/O) and our popular MPG101B Hand controller
Feature Expansion Plug for Digital Torch Height Controller and Isolated Spindle Speed Controller
Compact SMT design minimizes mounting footprint to 2.75 X 5.0 sqr inches
Uses external +5 and +12 supply (+12 must be isolated with a separate ground).
Pricing with Optional 3 output power module (third isolated supply will drive up to 100ma for other features to be announced) is less than most other single powered/isolated BOB's
Comes with  25 pin expansion cable for external I/O  (to Remote Table I/O card )

[Bernd]

Got the link safley stored in my favorites. Looks like quite an impressive source for boards.

Will have to go through their site later when I have more time.

Thanks for that link BTW, appreciate it.

Bernd

[Gadget]

I got my plasma torch/router relay BOB from them, it works great.

[Bernd]

I said I'd report as soon as something moved forward with this subject.

I've got the computer parts all together and have a computer up and running. Now here's the interesting thing. I may have more computer than I need. I figured I'd need some of the modern equipment that is out there, but it looks like I may have over estimated what I needed. So, below is a list of what I've purchased so far. Remember you need a computer to run Mach2. That's what I'm checking out right now.

Mother board: Asus P5N-D nForce 7501 set Socket 775
Hard Drive: Western Digital WD5000AAK Caviar Blue 500GB SATA
CD ROM: Lite-On IHDP118-4 Internal DVD Drive
Video card: BFG GeForce 7900 GT OC/512MB GDDR3/SLI/PCI Xepress/DualDVI/HDTV
Powe Supply: Ultra LSP750 750-watt power supply-ATX, SATA-Ready, SLI-Ready
Memoory: OCZ SLI-Ready Dual Channel 4069MB PC6400 DDR2 800MHz
CPU: Core 2 Duo E7500 2.93GHz
Monitor: Compaq Q2195
Keyboard: Microsoft Digital Keyboard 3000
System Software: Windows 7 Professional

Very easy to setup and had it running in about an hour from a complete dead start. Windows 7 loaded with ease. No problems or lengthy wait like the older versions. Quite impressed with that part. Loaded and played with a few other programs. Connected it to the net, really fast.

First problem I encountered was trying to play a video on You Tube. Told me I needed a Flash Player. Ok, no problem. Went to download the Flash 10 player for this system. Guess what? Nothing compatibale for this system. Mmmmm interesting. So I loaded one from the disk that came with the mother board. Still no go. Could I have to much of an advanced computer here? Figured I wasn't going to use the computer to surf the net since I was going to dedicate it to the CNC machine. Next I loaded up the software for Mach 2, the demo version. The screen wasn't very easy to read. For some reason the Mach2 screen wasn't printing the screen very clearly. Wish I had taken a picture to post.

So I tried it out on my every day computer and Mach2 works fine. The everyday computer runs Windows XP Home version and the screen resolution is lower also as compared to what the new monitor wants to run at.

There's more that I tried but wasn't successful. I'm now as I type this trying to see if I can load Windows XP on it and see if it will run with that.

I also printed out the two manuals that come with the Mach2 downloaded software. I noitced a 2004 date and a mention of Windows XP and 2000 versions.

If the earlier version of Windows dosen't run on the new computer I'm going to set up one of my older boards that I kept and us that. So stay tuned as I experiment.

Oh, BTW, the new system came in at under $1000.00, not bad I think for so much power. If it dosen't work then I'll have a new computer to work with when this one dies. 

Bernd

[Bernd]

Well, Windows XP Home Edition loaded just fine onto the new computer. Mach2 Demo works fine, but the screen resolution is still a bit hooky. No matter what resolution I use the lettering doesn't come out to good. But I think I did find one res that will work for now.

I've got the manual all printed out, so it's time to study and play with the program. Now I can concentate on making parts and specing out the motors and lead screws for the rest of the router/engraver.

Bernd

[Gadget]

If you have the time Bernd, you should check out Ubuntu Linus with EMC2. It is a single disk install and the entire install is free. I use EMC2 on my CNC table and have had great results with it. Free is good!!
Dan

[Bernd]

I've heard about all that you mentioned. Thanks.

I did get everything working with Windows XP Home edtion so I guess I'll keep on right now and see what happens.

Bernd

[madjackghengis]

Hi Bernd, you mentioned making your own board, and deciding against it, because of the acids and such, I used to work at a burglar alarm factory and we made all our own boards for proto-types, and it was pretty easy, not too messy, and not much danger.  We got a positive film image done by a photo shop, used black double sided copper board, sprayed photo etch resist on it, laid the film image on the board in a glass faced frame to hold it steady, took it out and left it in the sun for a minute or two, then etched it using ferric cloride, which doesn't work as fast as sulfuric acid, but with an air pump from a home aquarium, bubbling through the solution, it would etch and eight by twelve sheet of boards in a couple of hours at most.  The hardest part was drilling out the hundreds of holes using carbide drills, as they are all that will live through fiberglass board material for very long.  On some of our boards, we went as far as dip tinning them in a solder pot before assembly for higher current capacity and easier soldering.  I'll admit, I haven't done it since 1982, but for one off circuits, it's still a good way to go cheaply. mad jack

[Bernd]

Mad Jack,

What you just desribed I have done when my interest in making circuit boards was high on my list of things to learn how to do at home. I still have some of the chemicals around to do boards. I think I'll design them but have a board house do them. There's a place in CA. that you send your board design via e-mail and in a couple of days you have your boards. More on this once I get a bit more info.

On a side note and a bit  I've noticed that I have more projects started than I'll probably have time to finish in the next several years. Guy's like you and Don Squire will keep me on my toes and honest about my forgotten projects that I need to get done.       

Regards,
Bernd

[madjackghengis]

Bernd, that very problem is one of the reasons I'm on this forum, as I have a "Tiny Power" Ajax steam engine partially started, two different Stirling engines partially completed, a radial engine which only got proper attention once I got on this forum, an 18 seventy something shaper to rebuild and put back on line, a similarly aged LeBlonde lathe needing a rebuild, and a few other projects needing me to get a kick in the pants to get back on, so I expect some pressure from you as well.  I appreciate the info about the board service, I haven't made a board since the internet came into existence, I think the last one I made was in 82 or so.  I want to get into casting some things, but I'm not going to get that going until I get some of these other projects done.  This is particularly important since all too often, what I need to do next is fix a machine or some problem on a machine, to move forward on projects on hold.  The cam for the radial engine is on a rotary table indicated in, and waiting for a milling cutter to arrive, to cut the cam lobes.  Anyhow, we can kick each other from time to time, and maybe get half of what we started, done before that last call. mad jack

[Bernd]

Ok Mad Jack I'm in. We'll kick each other to keep those projects going.

Let me gather that info for you the circuit boards. Ah, just found it on my other computer. Here's the link. Express PCB Free PC layout software
You download their software, design the board, send the finished design to them via e-mail and they send you the boards in a few days.

I started the Gingery charcoal furnace many years ago. Then I converted it to a propane fired one with a Ron Reil burner. Here's Ron's foundry page. Foundry Page

I'm afraid to add up all my projects I've started.

Bernd