[dgentile]

Let me be blunt for a moment: I've been working as a machinist / bladesmith & fabricator for two decades or more ... but only just recently made a jump and did a CNC Conversion on a G0704 Clone (BF20) I had from a different project.... I've had brief experiences using an old, dated and not very flexible small industrial milling machine that had a bad fagor 8025m controller - but I have to admit my CNC knowledge is VERY LIMITED...

And here's something I struggle with "grasping":

I have several tools in their individual BT Tool holders... Got a 3d Probe (both a manual indicator one and an electronic probe connected to the machine) ... I've got a manual tool-setter (the one where the tool presses down on a pin and that moves a dial indicator) as well as an electronic tool setter (not yet hooked up to the machine)

The machine itself has limit/home switches (inductive NPN) so it can home quite accurately.


So far I've been doing the tool setup like this:

1. HOME the Z-Axis (at least the Z)
2. Insert a tool, as a first tool I've set up the Probe, and given it Tool No. 96... (UCCNC max. tool number is 96)
3. Probe down until it meets the tool setters reference surface...
4. Put the Difference (for example -240.330mm) as a tool offset into the controllers (UCCNC) tool-table for tool #96.)

Repeat 2-4 for each other tool.... numbering them 1 to XX

then when I want to mill a part that I've designed in Fusion 360
I do this:
1 Load Tool #96 (the Probe)...
2. G43H66 to load the Tool Offset for the Probe
3. Probe the work piece and use it to set the G54 work coordinates to X/YZ to ZERO.
4. run the G-Code ...

it does work.


However I've read and seen, that you'd rather touch of the base of the spindle and use this as ZERO ...
then measure all tools as an offset to this, and the offset will be the actual stick-out-distance of each tool including it's holder.
...
but this approach would require to touch off the spindle on the tool setter every time I want to do tool-adjustments?


Or am I looking at the entire thing wrong?...
old-school machinist being confused here...
any help is appreciated..
thanks!

[the_gentlegiant]

.....However I've read and seen, that you'd rather touch of the base of the spindle and use this as ZERO ...
then measure all tools as an offset to this, and the offset will be the actual stick-out-distance of each tool including it's holder.
...
but this approach would require to touch off the spindle on the tool setter every time I want to do tool-adjustments?


Or am I looking at the entire thing wrong?...
old-school machinist being confused here...
any help is appreciated..
thanks!

Forget you ever heard that nonsense about touching off the spindle face. I see some youtubers doing that and find it absurd. Under what circumstance are you ever going to be cutting anything with the spindle face??? It's a terrible choice for a reference. Half the time you might have fixtures or obstacles of some kind in the way were you cant get the spindle nose close enough to touch off anyway. They are also constantly using the Relative position display. Another waste of time and effort. I've set thousands of tools on thousands of jobs just like or a lot like you're doing without ever looking at it. No problems. In 20 years I've probably used the Relative display five times, just to check something.

What you're doing is a perfectly good way to do things. The only thing you care about is what the Machine Coordinates Display says when you touch your tool off on Z Zero, or some other standard repeatable surface you've chosen as your master. (I know the spindle face could be used in a backwards fashion as this, but it's still a terrible idea.) Who cares how long the tool is from the spindle face? You're only concern is how far it is from the workpiece. Note that if you're using an offline tool presetter, that is a whole different story, but that's not your case here. Let me put it this way... never once have I ever touched a spindle face to anything. If I did it would be a crash.

Good luck with your CNC endeavors. You're on the right track.

[dgentile]

Forget you ever heard that nonsense about touching off the spindle face. I see some youtubers doing that and find it absurd. Under what circumstance are you ever going to be cutting anything with the spindle face??? It's a terrible choice for a reference. Half the time you might have fixtures or obstacles of some kind in the way were you cant get the spindle nose close enough to touch off anyway. They are also constantly using the Relative position display. Another waste of time and effort. I've set thousands of tools on thousands of jobs just like or a lot like you're doing without ever looking at it. No problems. In 20 years I've probably used the Relative display five times, just to check something.

What you're doing is a perfectly good way to do things. The only thing you care about is what the Machine Coordinates Display says when you touch your tool off on Z Zero, or some other standard repeatable surface you've chosen as your master. (I know the spindle face could be used in a backwards fashion as this, but it's still a terrible idea.) Who cares how long the tool is from the spindle face? You're only concern is how far it is from the workpiece. Note that if you're using an offline tool presetter, that is a whole different story, but that's not your case here. Let me put it this way... never once have I ever touched a spindle face to anything. If I did it would be a crash.

Good luck with your CNC endeavors. You're on the right track.

THANKS A LOT.

Really, you don't know how glad I am to read what you've written... I've been trying to bend my head around that thing with the spindle...
Glad I've been doing *something* right ...

CNC's got a bit of a learning curve attached to it,... thanks again.