Hello Guest it is March 03, 2021, 11:23:37 PM

Author Topic: Starter questions...  (Read 4308 times)

0 Members and 1 Guest are viewing this topic.

Starter questions...
« on: February 03, 2009, 02:48:02 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.
« Last Edit: February 03, 2009, 02:51:12 PM by tomstefanou »

Offline Hood

*
  •  25,838 25,838
  • Carnoustie, Scotland
    • View Profile
Re: Starter questions...
« Reply #1 on: February 03, 2009, 03:04:08 PM »
1. G61 is Exact Stop G64  is Constant Velocity
2. Not sure, usually CAM calculates a true path for the dia of the cutter you have, if it doesnt then you will need to use Comp I think. What CAM are you using?
3. Possibly use Input 1 to inhibit the execution of G Code.
4. Use the Ref All button and it should do that. Also having a safe Z set will move the Z up before X and Y in many other situations such as Go to Zeros ect.
5. Not really sure what you are meaning here, maybe all you need to do is set up the tooltable?

Hood
Re: Starter questions...
« Reply #2 on: February 03, 2009, 03:50:33 PM »
Thank you very much for your rapid replies but still have soe questions...

1) How does it know when to use G61 or G64?
2) I am using SheetCAM
3) Is this a setting in Mach3?
4) If i got it right i just have to enable Safe Z option?
5) I have 9 tools that will be placed in the same position after they are used... so the real question was how to instruct mach to get each time the correct tool from the right position and furthermore how do i set up all these tools?

Thanks again,
Tom Stefanou.

Offline Hood

*
  •  25,838 25,838
  • Carnoustie, Scotland
    • View Profile
Re: Starter questions...
« Reply #3 on: February 03, 2009, 04:03:18 PM »
1. Your code needs G61 OR G64 in it, you will probably have to edit by hand. You could also look at the CV settings which allow you to set the angle at which CV or ES is used. Its on General Config page.

2. Afraid I have never used SheetCAM so cant help :(

3. Yes, lower left of General Config page.

4. More than likely it will work for what you are needing

5. Still not sure what you are meaning :( If you are meaning that you have 9 tools that you will place in the spindle then all you need to do is enter the tool offsets in the tooltable and then when you put a tool in call the tool number in the code. If its an automatic toolchanger then that will be a more complicated thing to set up and you would need to know how it worked and what I/O you needed for it.
Hood
Re: Starter questions...
« Reply #4 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.
Regards,
Ray L.
Re: Starter questions...
« Reply #5 on: February 04, 2009, 12:21:43 AM »
Thank you for your replies...

1) The problem is that when i use cv all the time when i draw circles these don't have smooth lines but rather have many many small steps.

2) Well, i will be as descriptive as i can...
We have the motor with the head for the tool change, and when you are in front of the machine you see the disc motor that is on the left of the router motor. This motor has the ability to change directions, and i mean by that that it can align to disc to cut along X or along Y. The point is how i can find the center of the cutting disc related to the router as some times disc will have to continue a job where the router was and vice versa, and of course how to make this be done automatically.

3) I probably did not explain it well, when i say the main console i do not mean the main mach3 screen, but the control panel that has the various switches on that control the machine.

4) Explored that folder and opened the files it included but did not find anything relevant to homing... Looked at Mac3/macros/Mach3Mill

5) ...

Regards,
Tom Stefanou.
Re: Starter questions...
« Reply #6 on: February 04, 2009, 10:58:00 AM »
Tom,

1) Can't help with that, but I'm sure Hood, or someone here, will have a solution.

2) OK, so if I understand correctly, you basically need to offset the tool position when using the disc, right?  If so, you can do this in the post.  You'd have to modify the OnToolChange method, so the post knows when you're using the disc tool.   You'd then need to modify all the motion methods (OnRapid, OnMove, On Arc) to add an offset to the commanded positions before outputting the moves to the G-code file.  If you have programming skills, look at the post you're using, and it should be reasonably self-explanatory.  Make a copy of it, and start modifying it.  You'll get the hang of it pretty quickly.  I've modified the hell out of mine....

3) OK, an external control panel can be controlled either by a macro, or a "brain".  Watch the videos on the Artsoft website to get an idea of the capabilities of these.

4) OK, there is a button script that controls homing.  Go to Operator->Edit Button Script, and click on the Ref All Home button, and it'll bring up the existing script, which you can modify.

Regards,
Ray L.

Regards,
Ray L.

Offline Hood

*
  •  25,838 25,838
  • Carnoustie, Scotland
    • View Profile
Re: Starter questions...
« Reply #7 on: February 04, 2009, 04:49:44 PM »
Circles with small steps should run better in CV than Exact Stop. Your problem however sounds like your drawings may be the problem, circles should be made of smooth arcs rather than lots of small lines.

For the external control, you could use Input 1 as I mentioned earlier, if you had a switch for your spindle that had two sets of contacts then you could use 1 set t switch your spindle on and the other set to Input1. If on General Config you chose the Programme safety Lockout option it would stop any code when the Input was active. You could of course also have a brain or a macropump to do that but as its already there then its probably the easiest way.

Hood