Messages

11

General Mach Discussion / Re: USB Breakout board for Mach3

« on: June 21, 2011, 09:21:43 AM »

Tweakie I'll gladly be the first, just waiting for someone to send me the funds.....

There are options which has free shipping to US (which is not where I am...)

I'm also strapped for cash, that's always been the delay for building my own. I work for an university and used their spare board for my friends lathe project as he wanted to test first before going any further. They needed the board again at work so his machine is standing again. I was looking for a simple LPT/USB design which I can make myself when I decided USB would probably be better especially compared to the local LPT version.

They will only get my questions at 9AM Beijing time, so I'll still have to wait a bit I suppose.

I didn't think to ask about the driver as they said it does not need any, but further down on the page they tell you to copy a dll to the Mach3 folder??

Will keep you guys posted!

Best Regards

12

General Mach Discussion / USB Breakout board for Mach3

« on: June 21, 2011, 06:34:47 AM »

Hi Guys,

I've been tinkering around with Mach3 here at work with a student built CNC mill and also helping a friend with a small Emco CNC lathe upgrade. With all the tinkering I really decided that it is time I get my own breakout board to play with at home as I have had a long interest in building my own machine.

Currently it would seem as if only LPT port breakout boards are available and the USB versions are either lacking in functionality or has poor support or are just plain expensive. I have some old PCs lying around at home but think going the USB route is the logical one. The board I'm currently interested in can be found at: http://www.alibaba.com/product-gs/445057014/4_Axis_CNC_Breakout_Board_Mach3_USB_Interface_Board_Capable_with_Windows2000_XP_Vista_etc_.html

From what have I read it has most of the things I would want. Although it has no relay output, it is easy enough to add that later with another PCB. The price also compares well (hardly any difference) with locally supplied LPT board with similar functionality.

Has anyone ever bought one of these? Know of compatibility issues? Know of other similarly priced USB boards? I've contacted the supplier with some questions and am awaiting his reply but thought I'd ask here as they claim it is Mach3 compatible (R3.042.040) which would mean someone must have tested it...

Best Regards

13

General Mach Discussion / Re: EMCO Compact 5 lathe with Mach3

« on: December 21, 2010, 12:37:35 AM »

Thanks Hood,

Ok will check that, but bear in mind that the stepper is going in the right direction. It is just as if during a Gcode run it loses its position in the X axis and always in the same direction. Like I mentioned, if you make a part and run the code again it takes more material off, and again and again.... eventually you have no part left!

The reason we converted the EMCO was because we could not get the Gcode to repeat as it would not "remember" the code when you pressed rewind. I feel that we have not really made any improvements with the conversion yet.... It remembers the code but not the position....

Does the Mach manual explain the prechange and the effects of the active state and reverse settings? I would like to read up on it to check the logic behind it.

Regards

14

General Mach Discussion / Re: EMCO Compact 5 lathe with Mach3

« on: December 20, 2010, 01:39:07 PM »

Thanks Guys,

These are some very useful replies. When I next go to my friend I'll try it and see what happens. Any explanation as to why it only happens in one "direction", if one may call it that? My theory is that if the stepper is losing steps it will do so in the X+ and the X- and thus almost cancel itself out?

Regards

15

General Mach Discussion / EMCO Compact 5 lathe with Mach3

« on: December 20, 2010, 04:08:31 AM »

Hi guys,

My friend has a EMCO Compact 5 lathe which I have equiped with Mach3 using some Gecko's and the original steppers. We can turn pars but the X demensions were not perfect. I did not know the "steps per mm" so we played around to get it to work. It turned out to about 392 or so. I've set the feed max to about 150 and only go up to about 100.

The problem we have been experiencing is that if you run the same code again and again the parts get smaller! I wrote some G code to turn two steps on a part and on every run of the code the steps are fairly accurate except that the part diameter gets smaller every time....

The DRO tells us that the machine is at x5,z5 as I have told it to do in the code. We set the 0,0 point on the tip of the part and made it use absolute values. When the code finished the DRO says it is at x5,z5 but in actual fact it is more like x-3,z0 although the Z does lose its accuracy over a few repeats of the code.

We first started with a fillet wizard and thought that the wizard was faulty but that was not the case. I think if the steppers were loosing steps then it would happen in both directions of X not just the X-???

Any help will be greatly appreciated!

Regards