Yes Another Newbe Asking Questions

[rdmotors]

I know you may have heard this all before....But.....


I am trying to formulate a plan to “get into” CNC machining and my first question is:

Is this circuit a “good” circuit? http://www.doc.ic.ac.uk/~ih/doc/stepper/control2/3axis/

I have seen and read a lot of posts for purchasing boards and building, but no one has commented on this exact design. So I am just wanting to confirm that this will work with some small 5 wire (yes I am going to say it) HP stepper motors. Don’t worry this first machine will be small. I just want to get my feet wet, but not get shocked.

Side note:

Why not buy……..well I am married and most of you single guys wouldn’t understand. Plus she handles the money so I am in a little pinch. I have done a lot of research and looking around and think I can build the complete 3 axis controller for under $40 dollars.

[DAB_Design]

Sorry I can't help with your question.

But you may be interested in this http://www.cnczone.com/forums/showthread.php?t=8506

[TinkerDJ]

I have actually built the board from this schematic and it worked fine. Easy to build and cheap its from the mid 90's that design. Problem is that the ucn5804b chips are now obsolete. There are far better chips out there now. Check out Phils page, pick one of the designs that you would like to build and go from there, they are basically going to be about the same amount of work as that design of board. If your looking for a 3axis board look at tachues design. After you build the 3 axis board you can go ahead and build the chopper driver. They are not that much money as long as you look around for the parts.
http://pminmo.com/

If your looking for cheap components try the electronic hoard. Although i haven't bought from them, they seem to have some decent prices.
http://www.electronichoard.com/

No worries on using steppers from printers, thats were most of us started playing around. If your looking for a good webpage for beginner stuff check out Franks page.
http://www.theworkshop.ca/index.htm

[H500]

The problem with the simple circuits is that the performance is extremely poor. At first it might be enough just to get the motors turning, but you will become dissatified very quickly.

The lowest cost "no compromise" circuit is based on the a3977 chip. They cost about $6USD each and the circuit is not much more complex than the one you showed. There's a toner-transfer ready design in the open source forum. Alternatively, you can buy a bare board for about $10 per motor.

[rdmotors]

Dab Design,

I am nowhere good enough to compete in a graphic design challenge. Plus what have been already posted are some real knockouts and I would feel more than embarrassed to post anything I could come up with.

Took me 10 days to get up enough never to sign up here and start a thread.



Dave,

Yes I have found out that the chip set is obsolete but I found a replacement for them and the price is pretty good and I am in the process of buying them now:

High Voltage, High Current Darlington Transistor Array
MC1413P, High Voltage, High Current Darlington Transistor Arrays, 16 Pin DIP, ON Semiconductor.
The seven NPN Darlington connected transistors in these arrays are well suited for driving lamps, relays, or printer hammers in a variety of industrial and consumer applications. Their high breakdown voltage and internal suppression diodes insure freedom from problems associated with inductive loads. Peak inrush currents to 500 mA permit them to drive incandescent lamps.
Features:
• Output Voltage: 50V
• Input Voltage: 30V
• Collector Current, Continuous: 500 mA
• Base Current, Continuous: 25mA
I appreciate the heads up on The Electronic Hoard they are the first ones I have saw that take paypal! Now I will have to convert my parts list to there p/ns and see about ordering the other pieces I need.

I have crawled all over Frank’s web page and it is one of the many inspirations that have started me down this road.

You bring up another question. I don’t HAVE to have the chopper board right away if I am using it for low voltage low amp motors. Correct?

[TinkerDJ]

Yes you don't need it right away, but then you need suitable ballast resistors. You will need some way to account for the current in the circuit since you will be using a higher voltage on the motors then what they are designed for. There is a thread in here somewere that has the formula for what you need for ballast resistors with such and such a voltage. I worked mine out when i was using the 5804 board and they came really close to 10ohms. I have 6 10ohm 10watt resistors. The resistors use power so they are slower then chopper or pwm designs. Alot of the really cool chips that you can get from allegro have built in pwm and can be got as samples. I'm currently working on a sla5071 chip board design. single sided with large traces. Actually it could be made on a perf board. This is one of many things i am trying to get out of the way right now. As well as a pic driven controller board that runs off the serial port.