Messages

11

General Mach Discussion / Re: Im new to the Mach3 program

« on: May 05, 2013, 05:14:21 AM »

As a follow up to Tweekie and Ian’s posts, it is also possible to use the mechanical end stops on a ‘small’ machine (Sherline in my case) without home/limit switches to zero the soft limits.  Jog   X Y and Z against their zero mechanical stops until the steppers stall. Press ‘Ref All Home’. The mechanical end stops are also very repeatable.
Al

12

General Mach Discussion / Re: Z axis not working appropriately

« on: May 05, 2013, 01:12:20 AM »

As noted in previous posts, the format of the DRO is not associated with your problem.  But if this annoys you (as it would me) then you can correct it. Bring up your screen.set in Screen4 and increase the height of the Z-Position DRO by one or two pixels. It should then revert to bold.
HTH,
Al

13

General Mach Discussion / Re: Home/Limits

« on: April 17, 2013, 12:25:32 AM »

I see that the software seller states that "We also include the Merchant Copy of the famous CAD software MACH3” and then again “MC Mach3 software" is included.
I wonder how he would respond to the question: What exactly is MC Mach3?
Is that now a recognized category for pirated software?
Buyer beware.
Al

14

General Mach Discussion / Re: initial machine setup - machine coordinates/soft limits javascript:void(0);

« on: April 07, 2013, 12:50:46 AM »

why isn't this mentioned in your documentation?

I believe you may have just unknowingly complemented Hood. He is not responsible for the Mach documentation. He is a fellow member of our forum. Due to his outstanding knowledge of Mach and his willingness to spend his time sharing and helping others he is sometimes mistaken as a member of the official Mach Support Team.  I suspect very few members can honestly say that they haven’t been helped at one time or another by Hood’s posts.
al

15

General Mach Discussion / Re: need help to output commands to coordinate just theta and x axis

« on: April 06, 2013, 11:56:50 PM »

If I read your question correctly, you want to use a rotary table in the C-axis i.e., mounted flat on the table with its axis parallel with the spindle.

I wrote an app to do the conversion but it isn’t exactly as straight forward as I would have liked.  There are several things to keep in mind that may require some hand editing
 
For example, in rectilinear coordinates we are used to seeing arcs made up of short straight line segments, but in polar it’s the opposite. Straight lines consist of short arcs.  Your CAM software can probably break the lines into segments for you.

Another problem is feed rate.  (The feed rate for each block is dependent on the current radius.)  For the A-axis Mach will do this conversion. It uses the Z value to determine the radius.  Unfortunately this feature is not enabled for the C-axis. I had to use G93 Inverse Time mode which has its own drawbacks. It seems to require a (much?) faster PC than any other file that I have ever run.  It runs fine on my desk top (1 GHz) PC but bogs down to a crawl on the older and slower machine PC.  

I will attach the app and two short sample files, the original rectilinear and the other one converted to polar with the feed in Inverse Time mode.

See how it goes; if we can’t get this to work there are other fall backs.

Al

16

General Mach Discussion / Re: X and Y axes jump when reversing directions

« on: March 31, 2013, 02:05:45 AM »

You might try going to Config>Backlash and see if  ‘Backlash Enabled’  is checked. If so uncheck it.
Just a thought.
al

17

General Mach Discussion / Re: 4th axis rapid not anywhere near X, Y or Z.

« on: March 28, 2013, 02:05:11 AM »

Actually Mach is seeing the feedrate in units/min which for the A-axis is deg/min.  As you noted 100 deg/min is very slow, (over three and a half minutes for only one rev!).
Mach can convert deg/min feedrate to in/min for a rotational axis. (It is a function of the radius).  On the settings page enter the nominal radius of the work in the A-axis ‘Rotation Radius’.  Touch off the Z on the surface of the work (to set the starting radius). Then during the cut as the radius (Z value) changes, Mach will calculate the correct feedrate in in/min.
HTH, al

As most 4th axis do, mine has a large gear reduction, 72:1 and further, a 3 to 1 belt reduction. When I am running code, the full rapids are at 100IPM for X, Y and Z, but the A axis moves at a snails pace.

I believe that Mach3 thinks that the A axis is moving at 100IPM, but because it is rotary and with such a heavy reduction, the rotation is crazy slow.

Oddly, when I am not running code and have the jogging feed set at 100, the A axis rotates at an appropriate rate.

Anyone have any ideas on how to fix this?

18

General Mach Discussion / Re: setup

« on: February 24, 2013, 11:41:41 PM »

Try this calculator, it may help.
http://www.machsupport.com/forum/index.php/topic,16315.0.html

19

General Mach Discussion / Re: 4th Axis Addition!!!

« on: December 28, 2012, 07:10:06 PM »

In Config>General Config>Rotational, check to see if ‘Rot 360 rollover’ is checked. If so un-check it.
That fixed it on my machine.
HTH,
Al

20

General Mach Discussion / Re: Go To Zero "Z" last?

« on: November 06, 2012, 04:08:36 PM »

Go to Config > Safe_Z Setup and select ‘Allow Safe_Z Moves’. Now Goto Z should move Z to the value entered in the Safe_Z box, then move X and Y to zero, and finally move Z to zero.
Al

Hi, I'm having an issue with my CNC.
When I hit "Go To Zero" the machine moves the "X" and "Y" simultaneously to zero, then it will move the "Z" axis to zero.
I would like the "Z" to go to zero first, then have the "X" and "Y" move.
Can anyone help?