Torch drops during cut

[Sam.Y]

I downloaded Fusion a while ago and use it at home to draw things but I’m very slow at it and have seen people use it for there plasma machines , but I’m use to AutoCAD at work which I’m much faster at drawing things. Most of the time I’ll draw at work then send a DXF file to my computer and cut it out.

[Kwikfab]

No worries. I just brought up Fusion because I used it for the CAM side of things as well.

You could just as easily bring a DXF from Autocad into Fusion for CAM, but you’d only do this if you didn’t own Sheetcam.

I just don’t know if the 0.5s rule exists for Sheetcam or not, but most definitely is a thing for Fusion CAM users.

[ds690]

The .5 second thing is a Firecontrol issue. It is mainly because they don’t use an “ok to move” signal from the plasma cutter.

Most plasma charts list the pierce delay based on how long to wait before moving, after the torch actually fires. They don’t start counting the delay until the torch is on.

Firecontrol starts counting when the signal to fire the torch is sent. It takes a few tenths of a second for that signal to get to the plasma cutter and for the torch to fire. That is why you need to add time to the published pierce delay times.

[ChelanJim]

Thanks David. Great explanation.

[TinWhisperer]

@Sam.Y

The .5 second rule DOES NOT apply to the XR

I used the settings straight from the chart cuts.

I have even used ZERO second pierce delay on my XR.

Here’s a quote from the horse’s mouth if there’s any question about the accuracy of my statement

@langmuirsystems

I can offer some insight into the pierce delay issue you are seeing as the XR Pierce Delay is calculated differently than the PRO or CrossFire Pierce Delay. The XR system (MCB/THC/FC) features a voltage feedback that starts the pierce delay “timer” when arc voltage is sensed rather than simply starting after the signal is sent as is the case for PRO/CrossFire. This should bring most pierce delays for XR back in line with “book” delays and is why you are having to reduce the delays from older programs.

[TinWhisperer]

@Sam.Y

IMG_84051920×2560 359 KB

this error can also happen when there’s a little bit of flex in the sheet and it pushes up against the nozzle after it does its initial height sense and kinda snuffs out the torch. When I’m cutting 26 gauge galvanized I sometimes run into this issue.

[Sam.Y]

That makes sense, I did notice a bow in the sheet in the middle while cutting, I had thought one of my slats was sitting awkward or not fully seated, and checked with a straight edge, some variance is fine because it will “self adjust” to a degree.

[TinWhisperer]

I’m talking about the first microsecond of cutting not during a cut. But yes The torch height control should adjust during the cut unless it’s during a period where it’s below 85% of its speed for corners or some other kind of path rules that you’ve applied to your cam.