Restart from line #

[jdwykrent]

So I was in the middle of a 16 hour cut on a piece of 1"x12"x12" Aluminum. I left for the night and came back to find that a custodian had powered off my control box in mid cut while the bit was jogging (not cutting). Grrrrr!

So I powered it back on with hopes to restart the cut from 6 lines before the shut off. I watched TJ's video on how to restart a project mid cut. Felt pretty confident that it wasn't the end of the world. Followed TJ's instructions word for word, clicked "go to", started the spindle, Warning sound (that the machine would be moving)... Z dropped to low, Machine Jogged, CRASH! Oh Fuuuuuuudge!

Broken bit & Damaged ego, I picked up the pieces and repositioned the work piece. Re-zeroed x y and z. I took a step back to re think what just happened.

- I followed the instructions.
- I made sure I was on the correct line of code (222,509)

What could have happened?

- Did the computer continue to run through the code after the machine lost power causing me to restart at the wrong code line?

- Did the machine lose the XYZ location after being powered off mid cut?

- Is there something I did wrong? In no way am I blaming anyone for the crash...

Second time's a charm...

[steve_g]

Jeff..
I haven’t watched TJ’s lesson on restarting, so I don’t know what was said… I’m sure you lost your zero when the power was cut. I know that supposedly some versions of SB3 are advertised as keeping their position when com is lost, but that has never been the case in real life for me! Also, the fact that power was cut mid jog would indicate there was some inertial movement after com was lost.
In your situation, I would have re-zeroed the same way I had before I started the job the first time, and continued on from there…
SG

[Brady Watson]

You want to open up the file via FE and goto the line where you want to start. Copy & Paste that line above where you are (so you have 2 duplicate lines) and change the M3 command to a J3 command.

So...If it said: M3,25.000,12.000,-0.125

You change it to read: J3,25.000,12.000,1.000 <--- Safe Z

Depending on your machine you may also need to turn the spindle on, so...you'll need to add it as well. If using FG it bypasses ALL previous code, including the MS command.

In FE you'd make your stopped line into this new set, leaving alone everything else:
SO,1,1 'Turn Spindle On
Pause 2 '2 sec to get up to RPM
TR,15000 'Optionally turning spindle speed up to 15000 RPM
MS,2,1
J3,25.000,12.000,1.000
M3,25.000,12.000,-0.125
... the rest of your file

There's always more that one way to do it...I can think of 3 or 4, but if using FG, that is how I do it.

You can also delete all the lines between where it died and the start header with your MS etc commands, then save out as a different name. You'll still want to add that J3,25.000,12.000,1.000 to make sure you Jog high.

Newer versions of the software work better than the older ones as the FG command was redone...

-B

[gundog]

With the SB I had mine would lose position by turning it off and powering it back up by a few thousands either in X or Y. You could hear it when it locked in with the stepper motors on start up.

If the machine set over night the Z would drift down a little. When the stepper motors are powered down the only thing holding the spindle are the springs. I think had you homed it with the limit switches and set your Z it would have worked the way TJ showed on his video.

Mike

[Doug Hawkins]

Did the same thing last week in wood. Need to zero x y and z before doing the goto comand. Lesson learned.

[jdwykrent]

Thanks guys. Questions answered. I thought about editing the code by deleting the lines I didn't need but found the video. Thought it would work, and it would have if I didn't loose my locations of x y and z.

The joys of being a school woodworking teacher... Title off he book I write when I retire in 20 years. 😄