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Lee Roberts
01-08-2007, 12:24 AM
i'v been looking at making my own motor controllers but have been advised from the guys over at http://www.rockcliffmachine.com that this can be tricky if your new to it, dose anyone have some links to a DIY site that i can get some more information about doing this ?

I have seen a site but never book marked the url and now i cant find it ?

SirMorris
05-08-2007, 10:42 AM
That looks like a very good price. Especially ready built. Once I'd bought all the parts and spent a week putting them together I'd spent a fair bit more than that...

It was fun though :D

The only thing I'd say is that having bought the PMinMO.com boards, I got an enormous amount of personal support from Phil Moore, the PM in PMinMO. It isnt obvious from the quick look I took at the site how much support there'd be. Though the smaller online vendors tend to be quite personal, so...

Overall I'd say they looked good.

John S
11-08-2007, 12:08 PM
Has anyone noticed that ArcEuro has reduced their small 3 amp driver to under £29 ?
Just a heads up that these have opto-isolated inputs and protection against shorting the motor wire, something that many others don't have.

Other pluses are self contained and dip switch settable for micro steps and amperage, no having to mess with a meter.

http://www.arceurotrade.co.uk/en-gb/dept_144.html

John S.

Lee Roberts
11-08-2007, 01:24 PM
Has anyone noticed that ArcEuro has reduced their small 3 amp driver to under £29 ?
Just a heads up that these have opto-isolated inputs and protection against shorting the motor wire, something that many others don't have.

Other pluses are self contained and dip switch settable for micro steps and amperage, no having to mess with a meter.

http://www.arceurotrade.co.uk/en-gb/dept_144.html" target="_blank

John S.

Thanks for pointing them out John ill add them to the venders section.

Yohudi
22-08-2007, 10:41 PM
I would suggest you do look at purchasing and would advise it for your first build, unless of course your very comfortable building your own like you seem. There is sites out there that offer good prices for packages that come with everything you need for the electronics side of things.

You could also try ebay, again these sites have shops on ebay that offer the same packages only that little bit cheaper.

I will post up some links for you with sites you could use, these will be uk sites of course.

Good Luck.
CNCUK

This is where I'd have to disagree with you I'm afraid. If you buy off the peg then you have very little choice in terms of voltage and current options. Most of the controllers that you see for sale on ebay and elsewhere are all hobby type setups really. Also you have to bear in mind the fact that most of the cheaper pre-built solutions are using proprietory hardware... this ties you to the seller for support and any repairs that may be required.

I considered a pre-built solution about 18 months ago when I was first building my machine. In the end I just built it.. and I'm certainly no expert in electronics. If you want higher end options for a low-end price then you just have to build it.. and having said that it's more a case of assembly than building. All you are talking about is connecting a break-out-board to some motor drives, a power supply and a few switches. Anyone can build a perfectly acceptable and safe controller.. to suggest otherwise is one of the many myths that seem to pervade the subject of CNC.

My own controller was built as 4 axis with the option to add 2 motor drives and run 6 axis at some point in the future. My general approach was to keep things as modular as possible. I used 2 break-out-boards to give me some encoder options on the rotary's I'm adding... these use more inputs than would be available via a single BOB. I use 2 x 48v 9 amp Solid-State ex-telecom'sPSU's they cost £39 each via ebay.. and I have an additional 80v 9amp PSU built into the case for when I go 6 axis. I have a pendant remote... a usb keypad basically which mach 2/3 allows you to configure in any form that you want from the point of view of controlling the machine. I have mains controlled by relays in terms of controller power and also external device power (Spindle /extraction). Motor Drives can handle up to 80/90V at current of 7/4.5 Amps each, I used different rated motor drives to meet requirements of motors, rather than paying for unrequired capacity . Price to buy this kind of voltage/current and motor setup pre-built was over £1500.00 and I would have had to buy it in from Germany.... UK prices were even more ridiculous.

My controller/machine build is fully documented on a blow-by-blow basis in my CNCZone build log. It includes a schematic/circuit diagram, which I've attached as well as a pic of the wired controller. I made a point of making my build log as comprehensive and complete as possible. It's much too big/extensive to transfer here and I won't do some kind of piecemeal cut up of a log I worked hard to make as informative as possible. It would defeat the entire object. I have upped a Zipped PDF of my components list and costs to date. If you're serious about building your own controller then you should check my build log at the links below.

Complete Build Log is at http://cnczone.com/forums/showthread.php?t=20656

Costings and Parts aquisition thread is at http://www.cnczone.com/forums/showthread.php?t=17834
hope this helps...

Lee Roberts
24-08-2007, 12:37 PM
I have my drivers and power supply now mate, i must say your log looks good i'm still looking through it now as i right this. I will be looking for the "ex-telecom's PSU's" on ebay though, so these would be a good choice for my drivers then?

i'v got a switched mode laptop psu that mike from routoutcnc (got his drivers) says will do ok, he dose say that there not the best choice.

Speak to you soon.

Yohudi
24-08-2007, 04:27 PM
I have my drivers and power supply now mate, i must say your log looks good i'm still looking through it now as i right this. I will be looking for the "ex-telecom's PSU's" on ebay though, so these would be a good choice for my drivers then?

i'v got a switched mode laptop psu that mike from routoutcnc (got his drivers) says will do ok, he dose say that there not the best choice.

Speak to you soon.


As you don't stipulate the voltage and current requirements of your drive/motor setup it's difficult to say if these power supplies would be any better for you than the "laptop" PSU you plan on using. Also you need to bear in mind that I bought my components more than 18 months ago.. so it's unlikely that you will find the same PSU still available.

If the supplier of your hardware has suggested the PSU in the pic then I would have to bow to his superior knowledge of your particular hardware. If you are looking for an alternative then it will need to comply with the hardware requirements. The PSU's I used actually output 42v unregulated at a current of 9 Amps....

hope this helps

Lee Roberts
24-08-2007, 08:43 PM
Hiya sorry danny is it ? my heads in a thousand places these last few days !

Ok please see this post: RoutOut CNC 3 Axis Driver Kit !!! (http://www.mycncuk.com/forums/viewtopic.php?f=64&t=47)

I have just updated it with the links, mike hasnt suggested a psu only given me advise on using the one i have suggested to him i would like to use. After talking with mike it now seems i cant use my motors at the full ampage as these drivers only support 2.5 amps, this wont be a problem for the work i'm looking to do and mike suggests i will be ok.