*PROBLEM* Piercing At Different Heights

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CrumpleNuts72
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*PROBLEM* Piercing At Different Heights

Post by CrumpleNuts72 »

This has been bothering me for a while now. I am using sheetcam and Mach 3. In Sheetcam I can set my pierce height to .1" and my cut height to .06". My table has a floating head (touch off) as well as a THC how ever the THC is irrelevant in this case. What will happen is on the first pierce, the touch off will work perfectly and pierce at the correct height and drop to .06" for the cut. Then, when it goes to the second pierce it won't even touch off and it will dive right into the metal and start its cut path. Ive experimented with the pierce and cut height in sheetcam. For example I put the cut height at .5" and again, the first pierce will touch off and cut at proper height then the second pierce will dive into the metal. And heres the kicker, Mach 3 tells me the Z-axis is at .500" when it is clearly not even close. What is causing my issue. Is there a way I can just make it touch off every pierce? And, just out of curiosity, shouldn't the Z-axis be changing as my THC working? Because like I said, even though the torch is dragging on the metal, Mach 3 is telling me that it is .500" off the metal which doesnt make sense. \
Any help would be greatly appreciated!
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acourtjester
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Re: *PROBLEM* Piercing At Different Heights

Post by acourtjester »

Ok so you know the THC does not take control until after the torch as dropped to cut height and a slight delay later, this is so the arc is stable when the THC comes into play. The THC should be changing the Z height as it moves along, if not maybe it has a problem. Another thing is there are things that need to be set in Mach 3 so it will look at the THC. Have you changed the post processor, it needs to be setup for your table electronics. A post processor setup of a Ohmic sensor does not function the same as a floating head setup. Could you have Mach 3 setup for metric and your using Inch this can through the distances way off. Say you cut a square for the first cut is it the correct size? Have you checked to see if you have slippage in the Z drive assembly. A pierce height should be about 0.160" you will ruin your nozzle piercing that low.
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c_rossman
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Re: *PROBLEM* Piercing At Different Heights

Post by c_rossman »

I have this issue from time to time, Its like the Z height gets messed up with the THC as its cutting. The bigger window I have for probing the worst it gets. I now have my window set at 50mm, so basically touches off every cut unless they are right next to each other. Change the refdistance to 50
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djreiswig
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Re: *PROBLEM* Piercing At Different Heights

Post by djreiswig »

I think if you have the * scale included and you are using inches your ref distance will be the equivalent of 50 inches instead of 50mm. If you simply have 50 it will always be in mm.
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