Messages

1

General Mach Discussion / Re: Spring loaded touch plates for Z auto-zero

« on: April 24, 2014, 07:49:10 AM »

This is what I know...

I can auto-zero onto my spring loaded plate, then enter G0Z1 on the MDI screen. I then check the bit height with a 1-2-3 block as a gauge and it fits under the bit perfectly time after time.

2

General Mach Discussion / Re: Spring loaded touch plates for Z auto-zero

« on: April 23, 2014, 07:30:48 PM »

This comprises most of the script that I'm using. Works great! Thanks for it!

3

General Mach Discussion / Re: Spring loaded touch plates for Z auto-zero

« on: April 23, 2014, 06:50:11 PM »

Thanks but I seem to have a script working. Did some research today and cobbled one together from examples in several threads here. Seems to be very accurate and repeatable. I'm using a spring loaded plate I made earlier.

The fine points on my v carving bits were taking a beating on the fixed plate. Even a slight overshoot can chip the tips, especially on the lower angled bits. Now they come down on what amounts to a cushion and I don't seem to have to sacrifice accuracy.

4

General Mach Discussion / Re: Spring loaded touch plates for Z auto-zero

« on: April 23, 2014, 10:11:26 AM »

Ok, understood, thanks.
Is there a macro that's preferred? I've tried a couple others with similar results so I obviously don't know a good  one from a poor one.

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General Mach Discussion / Re: Spring loaded touch plates for Z auto-zero

« on: April 23, 2014, 07:51:12 AM »

Z axis  info:

Steps  - 1622.5 / inch
Velocity - 250 in/min
Acceleration - 8 in/sec

Speed in the macro was set as F5

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General Mach Discussion / Re: Spring loaded touch plates for Z auto-zero

« on: April 23, 2014, 07:34:30 AM »

This is the macro I'm using.

-------------
Message( "Auto Zeroing..." )
If IsSuchSignal (22) Then
code "G31 Z-3 F5"
While IsMoving()
Wend
Call SetDRO( 2, .75)
code "G1 Z1.5"
End If
-----------------
I had a soft brass plate (non-spring loaded). In use it would develop pits from the bit coming down onto it. I do V carving and the tips some of my bits are very fine and would sometimes chip from the pressure.

As mentioned there's a lot of macros out there. If there's a preferred one I'd appreciate someone pointing me to it.

7

General Mach Discussion / Spring loaded touch plates for Z auto-zero

« on: April 22, 2014, 05:38:45 PM »

There's lots of threads about auto-zero Z macros, but I'm wondering about touch plates used with them. I recently chipped a new V carving bit when the macro went a little wacky and brought the bit down too hard on the brass touch plate. I've tried several of the auto-zero macros and all at one time or another have gone  a little nuts...often the speed will be much slower than usual or the touch will occur w/o a retract. It doesn't happen often but it does happen.

I've seen a couple spring loaded touch plates and these seem like they could save a bit in such a circumstance. I can't figure how they don't introduce errors though. If there's a spring it must deflect at least a few thousandths before mach realizes the touch happened. I suppose this amounts to backlash within the touch plate.

Any way to compensate for this and get a true zero despite the spring?

8

General Mach Discussion / Re: Starting and stopping

« on: February 26, 2014, 09:07:21 AM »

No other applications running.. It just stops, thinks for a couple seconds, then moves on.

9

General Mach Discussion / Starting and stopping

« on: February 25, 2014, 05:33:29 PM »

Saw the machine do something today - 3 times - that I've not seen it do before. It might have and I missed it, but never caught it in the act.

I was running a file that I've  run before with no issues when suddenly everything stopped. Mach's screen looked normal, no messages, then after a few seconds it started back up and went on for a few minutes, then it stopped again. It started back up like nothing happened, and after another 30 minutes or so it did it again.

All three times after stopping it started back up with no ill effects to the piece being cut.

Anyone have an idea as to why it might stop/start like this?

10

General Mach Discussion / Mach3 with PCI parallel card

« on: February 20, 2014, 11:58:17 AM »

Helping my brother - via email - venture into the CNC hobby. He's built a small machine and is now getting his electronics ready to go. His PC didn't have a OEM parallel port so he's ordered a PCI parallel card and will be connecting this to his breakout board.

Are there any caveats to be aware of when configuring Mach3 with add-on cards? I use an older PC that had its own parallel port so getting Mach3 going was a snap, so I have no experience with his setup.

Just trying to head off any potential problems in order to get him up and running with minimal fuss...

Thanks!