Messages

1371

General Mach Discussion / Re: Starter questions...

« on: February 03, 2009, 09:04:50 PM »

Hello, my name is tom stefanou, i have a 3 axis cnc machine.

i would like to ask a few things...

1) How can i instruct the post processor or somehow else switch to Constant Velocity when it draws a circle and to exact stop when it draws a rectangle?

2) The cnc machine has a router and a a cutting disc. The disc can operate in 2 directions. along X and along Y. How can i calculate and implement in the post processor the offsets required for the cutting to be correct and accurate?

3) I want to enable the router through a Start button on the main console. In case the router is not enabled i don't want to allow the user to start the code execution and also warn the user. Is there a way and if yes, how ?

4) I want to have a button that will find home position of all axes. first of Z then of X,Y. The point is that i want Z init to complete and then to start X,Y homing. I found the Command G28.1 Z1 and then G28.1 X1 Y1 but i want to insert a delay between them. How could i do that?.

5) I would like to make use of the tool changing functions using the atc post, the tools have fixed positions. i don't know how to do that at all.

Thank you all in advance for your help.

P.S Sorry for my bad english!.

Tom Stefanou.

1) In SheetCAM, you can insert a "G-code snippet" as an additional operation.  That G-code snippet can contain the G61 ro G64.   This, of course, requires each operation to be executed completely in one mode or the other.  The post-processor has no knowledge of whether it's outputting a circle or a rectangle.  You could apply the G61 or G64 to each G01 or G02/G03, but I suspect that would have undesirable side-effects.  Why do you want to do this anyway?  Seems a little odd.  Why would you not just run in CV all the time?

2) I'm not sure I completely understand what your machine looks like.  SheetCAM should do this for you, if the tool is setup properly.

3) This would probably require programming up a simple Mach macro, and modifying the screenset if you want to apply that behavior to the various "Run" buttons on the Mach screens.

4) Homing is controlled by the Homing macros in the Mach3/macros subdirectory.  You need to modify the macro there.

5) That also involves macro programming, possibly rather involved.  I haven't completely sorted that out myself yet....

Regards,
Ray L.

1372

General Mach Discussion / Re: What The????

« on: February 02, 2009, 01:37:16 PM »

I just installed the latest lockdown, and it's now correct.  Don't know how that got in there....

1373

General Mach Discussion / Re: What The????

« on: February 02, 2009, 12:23:59 PM »

what is the script in the button? sounds like its been messed with.
Hood

Hood,

'DoButton( 24 )
'DoButton( 23 )
'DoButton( 22 )
'DoButton( 25 )
Question("What Are You Doing?") 

I didn't change it.  This is how it installed - v3.042.015.

Regards,
Ray L.

1374

General Mach Discussion / Re: What The????

« on: February 02, 2009, 11:35:32 AM »

The Ref All Home button on the Settings page works as it should.  The one on the Program Run page brings up the goofy dialog.

Regards,
Ray L.

1375

General Mach Discussion / Re: What The????

« on: February 02, 2009, 11:28:19 AM »

Hood,

    I'm getting this with the stock 1024 screenset.

Regards,
Ray L.

1376

General Mach Discussion / What The????

« on: February 02, 2009, 12:15:44 AM »

I have Mach3 installed on my home laptop, for testing purposes.  I disabled all the home/limit switch inputs in Config->Ports&Pins. When I click the "Ref All Home" button, a little dialog pops up, with a title bar that says "Answer This:", the dialog says "What Are You Doing?", there's a text entry box with the number "0" pre-filled-in, and an OK button.

What the hell is that for?  Isn't there a way to clear machine coordinates with no home switches?

Regards,
Ray L.

1377

General Mach Discussion / Re: Setting Tool Length

« on: February 01, 2009, 07:18:43 PM »

Home switches I've got.  No problem there.  Where I have a problem is my small endmills (under 1/4"), which I mount in collets.  I have the larger ones in Tormach endmill holders, so those I can setup in the tool table no problem.  The small one I have to set the offset at the time they're called out in the program, since their length is not repeatable.  So, I still don't understand how to use my touch tool to set the length for these "loose" tools when a tool change comes around.  Seems to me the process would be something like:

1) Set the current tool to a reference position on the touch tool.
2) Swap tools, and move the Z axis to the same reading on the touch tool.
3) Note how much the Z axis was moved, and add/subtract this value from the offset for the previous tool, to determine and set the offset for the current tool.

So, let's assume I'm working with a part in the vise.  Machine Z zero is set to the table surface.  Work Z zero is set to the top of the work, let's say that's Z=5.  The reference position on the touch tool may be at machine Z=4.000.  So, when a toolchange rolls around, I move to work offset Z-1.  I swap the tool, and move the Z axis to get the same reading on the touch tool.  This is a shorter tool, so I've moved the Z axis down 1" to machine Z=3.000 get the same reading on the touch tool.  This would make the tool offset for this tool 1" less than the tool offset for the previous tool, so I do that math, and set the offset in the tool table.

I'd like the process to be automated, so I can just move the Z axis to get the correct reading on the touch tool, then press a button that executes a macro to do the math and set the tool offset.  Is that reasonable?  Is it the right way to do it?

Regards,
Ray L.

1378

General Mach Discussion / Setting Tool Length

« on: January 31, 2009, 10:14:17 PM »

OK, stupid question time:   I'm trying to understand how tool length is normally set.  What I've been doing is using a gauge block, which I set on the top surface on the top of the part, touch the tool to the block, then set the Z DRO to the block height.  This, of course, works fine, but I'm looking for something better.  I made a quick-n-dirty height gauge using a dial indicator, following an example on the Industrial Hobbies website.  But, I'm having a hard time seeing how to use it with Mach3.  It is intended to sit directly on the table, and you touch to tool to it, and lower the tool until the indicator reaches a specific reading.  All well and good for setting the height above the table, but all the Z positions in the G-code assume Z=0 is the top surface of the part.  So, if I'm holding the work in a vise, the top of the part may be 3" higher than the table surface.  So, how do I go from touching the height gauge, to correctly setting the Z DRO to the top surface of the work, without having to do the mental arithmetic, and typing into the DRO.  I intend to make an elecronic touch place, which would raise the same questions....

Regards,
Ray L.

1379

General Mach Discussion / Re: DigiSpeed-SD and CW CCW control

« on: January 31, 2009, 03:09:17 PM »

OK, I got it working properly.  In motor outputs under ports and pins I set up the spindle motor as step pin 14, direction pin 0.  Under output signals I entered output 1 as pin 8 and output 2 as pin 9.  In the spindle setup tab I entered CW as output 1 and CCW as output 2.  I wired pin 8 to relay 1 and pin 9 to relay 2 on the DigiSpeed board.  Now an M3 command will turn the spindle CW and an M4 with turn it CCW, M5 will stop the spindle.  I can enter an M4 command while the spindle is turning CW and it will stop and reverse direction without a hiccup.  Same with an M3 while M4 is running. 

An interesting item: When I first power up my lathe, both relays on the DigiSpeed board energize.  That means that my VFD is getting both a FWD and REV signal.  When the computer comes up and Mach is running, the PMDX-122 board enable the output signals and both relays on the DigiSpeed de-energize.  The VFD does not seem to mind the mixed direction signals as long as no speed is commanded at the same time.

Thanks for everyone's help.

Vince

You really should fix that power-up problem.  Someday, if one of those relays fails, your lathe will power-up with the spindle running, which could be dangerous.  Using the Mach charge pump should solve that problem.

Regards,
Ray L.

1380

General Mach Discussion / Re: DigiSpeed-SD and CW CCW control

« on: January 31, 2009, 11:14:52 AM »

My VFD is a GE AF-300.  As far as I can tell from the documents, it does not have a separate enable input.  There is a COM, FWD and REV input terminals as well as two terminals for the 0 to 10V input for speed.  If nothing is connected between COM and either FWD or REV it will not run. 

Peter, what you wrote is not clear at all.  I don't understand how the CW and CCW settings on the spindle tab can control the same output.  If I am using pin 8 and 9 for my direction (I am using pin 14 for the step), then I would set up the motor output for 14 and 8 (step and dir), then set pin 9 as output 1 in the ports and pins/output tab, and in the spindle setup and have both the CW and CCW settings control output 1?

Thanks

Vince

You need to setup one relay to connect COM to FWD, to be activated on M3/Spindle CW.  The other relay needs to be setup to connect COM to REV, to be activated on M4/Spindle CCW.  To do this, define two pins, each connected to one of the OUTPUT #n outputs, then go to Config->Portat & Pins->Spindle Setup, and put those two OUTPUT #n numbers in the two boxes under Relay Control.

Regards,
Ray L.