am exploring a couple of different approaches
The bog standard one which is just driving the stepper
- A friend pointed out some code on the forum which I had seen some time ago, forgotten about (probably because I could not grasp it at the time - I have had a quick look at it now and it makes more sense)
" 2.1.1.4. Boxford Lathe ATC toolchanger component
Component controls 8 station ATC fitted to Boxford 240, 160 and 125
Works on degrees of movement, with ATC defined as rotary axis, so does not require index sensors.
Should be able to be adapted for any lathe using a 'rotate past pawl and reverse to lock' methodology.
Amount of rotation configurable for fine tuning, see README and notes in .comp file for details"
wiki.linuxcnc.org/cgi-bin/wiki.pl?Contri...oolchanger_component
I am looking at having a compact unit and really like the idea of running it on a PI driving a mesa board, I also have a preference to stick with standard linuxcnc components (I know you can do all kinds of addins)
There are various mods that I can think of or have been suggested to me to get it to either index or read back which tool is in position
1) I had thought of a hall sensor and magnet (with swarf around is this a good idea)
2) I had a slip ring system suggested to me (Most accurate but possibly a little fiddly - I am not known for my finesse)
3) Trinamic stepper drivers are able to tell you when they have stalled and by doing this will confirm that a tool is selected and in position what it does not tell you is which one so some kind of indexing needs to be added I thought a limit switch and a divot in the back of the tool holder plate would give you a position to count from
I want to try and keep it simple
This is a side project
This will take me a while but when I get stuck or achieve something I will share or ask
