Messages

881

General Mach Discussion / Re: Hall effect home switches - Nonsense and bother

« on: February 26, 2008, 04:23:45 AM »

Reading the initial post, I think you have got very good results if you are accurate to a few microns, using Hall effect proximity switches. Bearing in mind these work on induced magnetism, then I think it is likely that things change on each pass. You might not be able to see, but even a slight movement in the table, or bit of metal about could affect it.

There was an old saying - don't bring a bucket near the ships compass, for exactly that reason.

I think the optical solution would be far more positive

882

General Mach Discussion / Re: video problem

« on: February 25, 2008, 04:02:44 AM »

Brett - Thanks for that - it is worth a try. I cannot see why the driver in Windows will not work, although, knowing Bill Gates, he would want a percentage of the lathes.

883

General Mach Discussion / Re: A million dollars to the person that can help me.

« on: February 25, 2008, 03:55:49 AM »

The offer of a "million" sure did the trick !!!

I've never seen as many orange and red flashes on a post in such a short time - or were we all having a weekend on the computer.

As long as this post isn't a reply to "prices for one on one technical support"

884

General Mach Discussion / Re: Manual to cnc lathe retrofit? feaseable?

« on: February 24, 2008, 04:57:23 AM »

All you honestly need is two stepper motors and drivers. ArcEuroTrade in the UK has some large steppers that would do it.

Don't try to get all singing and all dancing straight away. If you drive the cross slide and the main leadscrew that is all you need.

The advantage is the LATHE is the same, it is the one you are used to, so any little problems will be easy to deal with.

Mach 3 provides many configurations for backlash and other little things to get the lathe set up correctly.
All I did with my lathe was take off the operating wheel, and substitute a drive via a tooth belt.

885

General Mach Discussion / Re: opto interrupter wiring?

« on: February 24, 2008, 04:42:16 AM »

Yoiu may find the 5 volt pull up resistor on the input is too much. Most ports already have 5 volt internal pull up resistors.

I use much the same circuit for my rev counter but it didn't work at first. I soon found the input was never pulling down to zero (or close enough for the computer to register it). I removed the external pull up resistor (the opto does not need it) and it works fine.

In this case perhaps, miss out the breakout board and wire the input straight to the computer.

886

General Mach Discussion / Re: ellipical path in MACH3

« on: February 24, 2008, 04:33:30 AM »

GCode does straight lines and circles.

Having said that you can do any shape at all, what you have to do is control the axis yourself.

This can be done by  a Macro. These are written in Visual Basic (there is a tutorial video) and the full syntax is available.
There would be several ways of doing it.
e.g. for x = 1 to 100 (assuming mm) then
                  xa = x
                  ya = (whatever the equation is)
                  CODE (g1 x) & xa &(y) & ya

The Visual Basic runs in advance of the GCode and will write 100 lines of code giving G1 X*Y* instructions for positions of x = 1 to 100

You cold write an even more complicated one using g2 or g3 commands, having worked out the diameter of the elipse at that point - thus having the elipse in a series of arcs instead on straight lines.

887

General Mach Discussion / Re: video problem

« on: February 22, 2008, 01:39:41 PM »

Yes - this is exactley the problem I am having. These USB cameras do not come with drivers, they use drivers already installed in Windows. I had a similar problem with on board drivers taking over sound cards on my computer organ system as well.

Does anybody have a driver which we can install, to override the on board driver. This generally cures the problem

888

General Mach Discussion / Re: Driver issue on 3GHz Computer?

« on: February 22, 2008, 01:31:22 PM »

I think the problem was, with some computers, the on board video driver took up big chunks of the processing time, because of demands for super graphics for games etc. This was also prevelant on laptops. They also used big chunks of memory.

If the compuetr is dedicated to cnc, then check all the processes that are running, and turn off as many as you can. You do not need them. If you feel it is the on board graphics, and you should be able to see from the processes display how much usage the graphics are taking, get a graphis card and install it, then disable the on-board graphics.

889

General Mach Discussion / Re: 6axis screen, default X-Z plane, default feedrate problem

« on: February 22, 2008, 02:54:32 AM »

Yes - Mine is set on XY and I have not needed to change it. I have tried on this computer (which is not connected to a machine) and I can change it to XZ or YZ, but even if I save settings, when I close the program and then restart it, it always resets to XY

We will have to have help on this !!

I do not understand your feedrate - 6.00 appears to be in inches but 3000 appears to be in millimeters.
If you have set up your machine motors in inches then 6.00 is the maximum you will get - the figure does not change if you use G21 - you must change that manually.

890

General Mach Discussion / Re: can not find driver test

« on: February 21, 2008, 11:44:07 AM »

If you are running OK then you don't need it.

The program is in the Mach 3 folder - as a standalone program - driver test.exe