Hello, all,

I am just back from the NAMES show in Toledo.  It was a great 
show, and I talked to a lot of people interested in CNC.  Only
Fred Smith of IM Services, and Steve Stallings of PMDX were
there as others in the CNC field.  Oh, and Sherline, of course,
but they were not pushing their CNC line.

I saw the 1/3rd scale Ferrari by Pierre Scerri of France, and he
ran it, producing a huge cloud of blue smoke.  Lots of other 
incredible artistry, too.

I had my 150-Lb mini-mill there, and was running an 
uncharacteristically recent version of EMC2/Ubuntu.
I was demonstrating single point threading, with the mill
set up like a lathe.  I ran it a number of times, and started
having a problem with the threading.ngc program failing to
stay in sync with the spindle after being run several times.
At this point, I really can't say whether it is hardware, 
software or EMI, as we probably had 250 people in one room
with cell phones turned on, and 50 of them holding conversations
on them.  I'm just inquiring if anyone else has used the 
threading.ngc program, and what results you had with it.
I will be doing testing under more controlled conditions here at 
home to try to find out where this problem is coming from.
I attempted to nail down the problem at the show, and the only
data point I seemd to get consistent results with was that 
restarting EMC would guarantee one clean run of the program.
After that, re-running the program would sometimes cause it to
blast ahead instead of syncing to the spindle.  (Another thing 
which I am almost 100% confident is true, is that the spindle 
sync'ing either ran perfectly for one complete run of the 
program, or that it failed consistently for every threading pass 
on that program run.  A timing issue in the encoder logic would 
not know one program run from another.)  Anyway, this could be 
caused by the encoder counter failing to zero at the index 
pulse, while the driver sensed that the index pulse has been 
seen.  (Please don't remind me that this may be related to other
problems in the area of homing with index that I am still 
investigating, I am WELL aware these are almost entirely the 
same function.)

All comments are welcome,

Jon

-------------------------------------------------------------------------
This SF.net email is sponsored by DB2 Express
Download DB2 Express C - the FREE version of DB2 express and take
control of your XML. No limits. Just data. Click to get it now.
http://sourceforge.net/powerbar/db2/
_______________________________________________
Emc-users mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/emc-users

Reply via email to