Help wiring THC

[Vmax549]

Yep modify teh Post in Sheetcam to NOT add the surface sense routine . There is probably one already there to do that job. Ask on the Sheetcam forum.

(;-) TP

[Spoolnms]

I posted and guess well see. Thanks.

[Vmax549]

How often do you plan to reference teh top of material ?? IF only once then you can use a regular Mach3 post and then just reference teh machine before you start. Thet THC does not need any special code to work just make sure the THC control in UCCNC is turned on.

But if you plan to reference each time you pierce then it takes modifying the sheetcam post.

(;-) TP

[Spoolnms]

Per job would be ideal. And so if I zero the z axis on the workpiece, and sheetcam brings it up, with thc enabled in UCCNC it will automatically work?

Do you have any insight on modifying the post to allow it?

[Vmax549]

That would depend on HOW your THC works. Does you THC directly control Z height independant of UCCNC during cutting or does UCCNC control teh Z height while cutting?

Over at Sheetcam Les explained which POST for you to use with NO sliding Z switch . In which case you would only reference teh top of material once when setting up teh cut.

(;-) TP

[Spoolnms]

Sorry, missed this question. I have a Plasmasens Out that I program the desired voltage which gives an THC Up, THC Down or Arc Ok signal, which I wired into the C10 board. I programmed Up with up, down with down, and Arc Okay with Arc On. I am guessing this is wrong because running a program, the PlasmaSens is giving an up command, but the Z height never moves.

I have everything set per the below settings, and THC enabled on the run screen. Is there something more I need to do?

[Spoolnms]

OK, so figured out THC to work. However, the z work offset is changing for some reason. After cutting test pieces, the z appears to be lower than it was currently set. Ex. z-0 becomes z-0.2. Battling issues with it, sometimes it runs away from the piece, or crashing into it on the second cut. Does THC constantly update the z offset? Or is there some sort of interference making the z motor losing steps.

[beefy]

Your THC just measures a voltage, compares it to a set point, and gives up/down signals to UCCNC. It knows nothing about the position of top of material. Neither does UCCNC apart from the first cut when you manually reference it to top of material. So if the top of your material is not always perfectly parallel with your X and Y axis then your Z position will be off after the first cut.

I like most others have a floating Z axis, and the torch touches off for every cut so top of material is always referenced before each cut. Assuming your table slats were initially installed so the top of them was perfectly parallel with the X and Y axis. Within a short time slag will get crusted on top of the slats the when a sheet is laid on top, bang goes your accuracy. But even if that was not a problem the sheet often warps while it's being cut.

That's why the only way to ensure your Z height is correct for each cut would be to manually re-zero your Z before each individual cut. I prefer floating head and auto touch off

[Spoolnms]

But with each cut, shouldnt it be trying to get the set voltage that is set in the thc controller, so in theory it shouldnt touch. Or am i thinking wrong?

[Spoolnms]

According to UCCNC, when the torch crashes the work piece, its damn near close to 1/4" off. Something is changing the z offset.