[whutth]

I have a 4x8 shop saber sidekick and was in the middle of cutting a 48" piece when the torch lost arc. I want to restart the program at the point that the torch lost the arc to that I can finish and not loose this piece. On the WinCNC controller software it is not letting me use the restart button and I do not have clear instructions on how to re-start the program where it failed. Please anyone provide some assistance.

[Torchhead]

Your table vendor should be able to tell you how to restart a cut. A lot will depend on if you have XY homes and can get back to a table zero . In some programs you can click on a cut segment and it will highlight the G-Code line and vice versa but I don't remember in WINCNC. The key is did yoou lose positionand can yoou get back to either the part zero or the table zero
Shop Sabre makes really good routers.

[plasmamatt]

I also have a Shop Sabre with Wincnc that I have been using for about 5 years now. I have yet to find a way to get back to an exact point if the arc is lost while cutting. I don't think it's possible. The torch continues to move and I don't think the software records the location at which the arc was lost.

I have tried a couple things to try and save parts when the arc is lost while cutting. You can try and find the line in the g-code that is the closest location to where the arc was lost. Keep in mind though that the torch may need to run across some previously cut area. The torch height control (THC) is going to want to slowly dive into the steel. If it is just a short distance (less than 1") you will probably be fine (this will be dependent on how sensitive your THC is set). If it is longer you can try and finish the part with the THC off. I find it very hard to cut with the THC off though. Yet another option is to turn the torch off and run the program right up to the point that the arc was lost. At this point pause the torch movement, turn the torch back on and then resume the program.

If the torch comes down, touches off and then misfires then it is easy to find your place again. You can go into the g-code and delete everything up to the point of where the misfire occurred.

Hope this helps you.

[Torchhead]

So does the WINCNC have ARC OK ? Does the cut stop when you lose arc? That will show you approximately the point it stopped . You shouldbe able to note the line of code it stopped on and scroll back to the start point of that cut (find the M code that turns on your torch. If it has touch-off sequence that may be int he code so you want to start before that . If there is a command like "Set next ;ine" as in MACH you can set the line and hit RUN and it will charnk up and restart the cut. Now here is the "trick" since the cut is already thre you need to do two things: Turn off the THC and as soon as the torch fires you turn it off and let it "dry cut" the section up to about 1/2" before the spot it stopped and then manualy fire the torch again. As it starts inot the unclut metal you turn the THC backon. If the motion does not stop when you have the THC on and you lose arc then it gets a lot harder, especailly if you are not standing there to manully stop it. If you cannot step though the code and see the cut segments highlight int he toolpath display about all you can do is go back and tunr off your plasma cutter and do a dry cut from the beginning up to the pierce point of the cut where it lost arc and note the code line number . Then you can use the method above. Knowing where you are on the table at all times is important. That starts with knowing where you started. if you simply move your torch to some spot in XY space and zero the DRO's then if the software loses postion for any reason (some systems do on an e-stop ) then finding the exact starting spot again becomes a problem. If you have home switches on XY and always start from table zero and either use a work zero (part zero relative to table (absolute) zero or you simply move the torch out ot he new zero point and before you reset you write down the X and Y offsets ATHEN zero you can alwyas find the start point. There is almost always a way to get back and restart a cut if a little precut prep is followed.

TOMcaudle
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