Brother TC-225 / TC-229 adventure!

You're my hero! I totally missed the labels on the PCB. The relay board is mounted on the very left behind the circuit breaker and the labels are shadowed by the relays.

its a pretty organised machine, if you do it right, you literally alter nothing on the machine from stock, and just reroute a few cables to the mesa (or whatever youre using).

ihavenofish wrote:

this is from another thread
.ini:
[AXIS_2]
MAX_LIMIT = 0
MAX_LIMIT_TOOLCHANGE = 200

postgui.hal:
loadrt mux2
addf mux2.0 servo-thread
setp mux2.0.in0 #<_ini[AXIS_2]MAX_LIMIT>
setp mux2.0.in1 #<_ini[AXIS_2]MAX_LIMIT_TOOLCHANGE>
net extend_z_max motion.digital-out-10 => mux2.0.sel
net z-max-limit mux2.0.out => ini.2.max_limit

change.ngc:
M64 P#10 ; enable off-limit movement
G53 G0 Z[#<_ini[CHANGE_POSITION]Z>]
...
G53 G0 Z[#<_ini[AXIS_2]MAX_LIMIT>]
M65 P#10 ; restore z max limit
thanks!

You said you still haven't figured out a way to swap limits for the ATC. Did you have problems with muxing the limits as above? To me that looks like the most elegant solution. Much less configuration than a virtual W-axis.

i think that is what im looking for actually but i couldnt find an explanation of how to use it. i am trying to do SOFT limits in this case. the hard limits are only for emergency stop. the soft limits awe the travel ranges, which in this case would be 7"-17" (give or take) for the normal z travel. then swap 17" for 21" do tool change.

im gonna upload my hal/ini files tonight, and the toolchange.ngc. we'll see if we can finally manage to get this going correctly.

Could your tuning problem be electrical noise due to shared ground between field IO and logic? From what I've measured the relay board has it's own ground (labeled P.G. - power ground??) different from the controller ground (L.G. probably logic ground, connected to the case). Maybe you've connected them by wiring a servo signal to the 7i77 field IO.

Looking forward to your config files!

the servo drive is connected only to the enable +-, +10-10 and the 6 encoder pins. there is no other connection. there is a ground in the cable which has been left where it was on the cabinet. the drives are in no way connected to the relay board, only IO is on the relay board via ribbon cables. if there is a connection, it is one that's always been there.

noise on the line, and missed encoder pulses due to noise is definitely a possibility.

from memory, if i push the table by hand, the encoder feedback seems to be not as smooth as it should. its been a while though so i dont remember anymore.

alrighty, here's some files

Here is how I think I would attack this.
I would set up the soft limits for the full travel including tool change length. Then for the regular travel length I would set up something using the near component to trigger a user message and machine pause for the 17" travel. Then during a tool change it wouldn't be too difficult to disable the user limit you just created.

Why not setting the limits to the regular workspace? If a tool change is requested the upper limit is increased such that the spindle can travel to the ATC area. After the tool change the spindle goes down and the original limit is restored. Or am I missing something?

youre not missing something, thats exactly what i want, but i have not yet figured the correct method.

im 99% sure what you posted will do it, but i will need to see how to implement.

inside the toolchange.ngc you would need to trigger the z upper limit change. i have to get back into this on the weekend, and try to remember where i left off

but, we still need to tune the drives first, or this is all for nothing.