Manual tool change problem

From what I have read doing manual tool changes using tools held in collets and chucks that are not of a fixed length does not work if your job is all in one file. You can't jog the machine to touch off during tool change prompt. That is why you use one file for each tool.

I don't worry about what the tool number is. The only thing that seems to matter is that if create a part in Fusion 360 and used 10 different tools for the job I will have 10 files and must have room for 10 tools in the tool table. It doesn't matter what the tool table says they are as long at the length is zero. I load the file, put the tool in the collet/chuck. Touch off the Z to the top of the material. Press run. The Z moves to the top and a popup comes up telling me to insert tool # whatever. I already put the tool in so I click OK. The machine performs the operation. When it finishes the Z moves back to the top. I load the next file and tool, touch off Z and press run. If the next job uses the same tool or I had hit EStop and I am restarting the same job LinuxCNC knows that the tool that is currently being used is the same as the last program run and will not prompt for the tool change. It will just go about doing the job.

John

Hello - thanks for the replies but I would rather run the complete operation in a single file with multiple tools. It would seem that I am getting confused by the display. When I turn the mill on it is actually doing something different. I made the mistake of setting tool offsets as negative values which moved the mill to the wrong height. I have now changed them to positive values which now seems to give the correct distance between relative tool tips as judged by the change in tone as the Z-axis switches from rapid to slow feed rates at 0.118" above the theoretical material (no actual material or tool in the mill yet) - measured with tape measure from bottom of headstock to bed, so only approximate values. All well and good, the only problem now is that it is trying to do the tool change way below the material level! I must have something configured wrong, but what? attached are my .ini file, a sample test program and the tool table (renamed with a .txt extension as this will not allow me to attach a .tbl file).
I am now intending to set the tool change at the top of the Z-axis slide (it already does if the tool offsets are negative) and make sure that all drills are seated hard against the top of the tool chuck (which will give them a pedictable length), end mills will have to have a collar Loctited to them to give them a predictable length when fitted in a collet chuck.
Cheers

Second attempt at attaching files - it seemed to allow me to select files from across my local network, but failed to load them. This time I have copied them to the local PC. Now to see if that works any better.
Oops - seems I was clicking on the wrong bit of the attachment button when trying to look at it.

It looks like you don't have home or limit switch, and you are homing to current position, your machine is parked. If you can park your machine at a defined xyz position, machine zero will be there after start,homing. Or set in [AXIS_2] home_offset= value from current position. Try to find a way, to make it repeatable.

There may be a misunderstanding about how tool lengths are handled in Axis.

If I have two tools set up in Axis with their lengths defined in the tool table as T1 = 20mm and T2 = 15mm, and then switch between two different tools in Axis (M6 T1 and M6 T2) the display of the tool changes to match each tool length, but the lowest Z- extremity of each tool remains at the same position. Axis assumes that each tool reaches the same amount from the collet, but the cutting length itself is what changes. That probably also explains why Axis does not attempt to physically move the Z axis on the machine when the tool changes to compensate for any apparent differences in tool length.

If you have room on your machine to add a touchoff plate, have a closer look at the post I linked to earlier for manual toolchange. You could probably even rig the subroutines to use a portable touchplate that you place on top of the work piece prior to each toolchange, and move out of the way after each touchoff has finished. The mentioned subroutines and remapping of the M6 toolchange command should allow you to perform multiple manual tool runs within the same G-code file without worrying about setting a precise tool height every time you insert a new tool in the collet.

You could probably even rig the subroutines to use a portable touch-plate that you place on top of the work piece prior to each tool change, and move out of the way after each touch-off has finished.

My portable touch-plate has a button on it that when pressed started the subroutine. The subroutine probes the Z slowly down until contact then moves one inch up. But, I still need to got the tool to when I am placing the touch-plate and that is what I have heard that you can't do while the program is paused for the tool change. I have not tried to do it myself. I actually find the separate files convenient when the operation doesn't yield the expected result like a chamfer that is too small. I just tweak it in Fusion 360 and run the new post.

John