4th Axis rotation angle limit problem

Thanks Andy,
I am very happy to have something new to try!

Should I use a different g-code to set speed and turn the 4th axis to "on"?

On a side note, would it be possible to use both the angular motion and velocity motion without changing to a different machine configuration by restarting LinC

I think the same as the OP, use my 4 axis mill to do some lathe like turning.*

I want to set my a-axis to "on" (degrees per minute) at the start of the program, then do some milling and at the end, turn 4th axis off.

Just as OP mentioned, I only see the option of breaking up the current code in to small segments as the only way you can get the 4th move together with other axis is to have the movements programmed on the same line.



* if this is not what OP wants I'll open another post but it seems he and I want the same result.

andypugh wrote:

Linking the A-axis stepper drive to an extra velocity-mode stepgen, with velocity supplied from a G-code M68 command would be a possibility.

One way to achieve this would be to use a custom M-code to rewire the HAL (for example M100 could delete the connections between the parport pins and the position-mode stepgen, and re-wire them to the velocity-mode one, and M101 could reverse that process).
Alternatively I can imagine doing it purely in HAL with logic blocks, though that might get unwieldy.

Unless you are doing production work it might be simpler to create two machine configs, one in which the A-axis is controlled as a spindle with speed controlled from the S-word (assuming that you intend to use a fixed lathe-like tool) and another for conventional milling. Just load the config you need for the operations you want to perform. My combo mill/lathe works this way. If you create a lathe-mode configuration you will even get lathe-mode preview in Axis, and tool shape etc.[/quote]

I had been looking for information about custom M-code after looking in to 3D printer software which also has to turn a stepper on and off. After seeing the M- code I thought that might be the way to go but I could not find the info that explained the basics.

I guess that part of the problem is that I do not have a technical background+ I am non native in English. Both of them separate never seem to be a problem but the two combined make for hard searching...

So if I understand correctly:

With the use of M-code I could tell the controler to use a different setting, actually turning the position guided axis in to a velocity axis and turning it back in to position if I need it.

I have the 4 axis setup working, is there any info available on how I can set up and use M100 codes for the purpose of setting the 4th to spin?

I indeed intend to use this in a production environment but for now just having it run to check if I can actually make what I need is fine.

Thanks andy!

If i read it correctly this is just to change the mode, what do I put in my g-code to spin the 4th axis?

Is it something like this?

And the M100 and M101 files go in to the same folder as the other configuration files I use for this machine?

Oe, that is dazzling

Let me give some of my basic here I left those out before:

XYZA configuration, nothing else configured yet (though I did try).
Spindle turned on manually

Want to try out milling acetal bearings with the 4th set up as a C-axis.
I have the contour ready to be milled in XZ plane and it shows up in axis.

I want to get my C axis to turn before the XZ movement starts and keep on turning untill all XZ movement is done.

It would be awsome if I could switch between position mode and velocity mode as it would open up a lot of problem solving options but for now I need to test if I can even make the bearings I have to make.

What do you think would be the quickest/best way to get there?