Need an explanation of touch off

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TAS99
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Need an explanation of touch off

Post by TAS99 »

I've read the post and watched videos but I'm still confused as to what torch touch off is.

Can someone give me an explanation of exactly what it is and the pros and cons of using it. The old plasma cutter I'm rebuilding has a float switch on the Z axis to establish torch height. Use both, only one, as yu can see I need an explanation.

Regards,

Tom
ShawnM
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Re: Need an explanation of touch off

Post by ShawnM »

Torch touch off is what tells the software where the top of the material is. Using an ohmic sensor or float switch, either way you need to use at least ONE of them. I have not used a float switch as my Hypertherm has the ohmic sensor. The ohmic sensor is by far more accurate especially cutting thinner material as the touch off procedure doesn't flex the thinner material like a float switch would. Again, you need to use one of the procedures so the software can set the correct pierce and initial cut height before THC takes over. There's good info in the plasma manual also.

If you have a float switch the setup procedure is in the plasma manual. Tell us what plasma cutter you have and can you add an ohmic sensor to it.
Joey
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Re: Need an explanation of touch off

Post by Joey »

Torch touch is comparable to ohmic. The torch has to have good continuity to the material clamp for the touch off to trigger.

If there is bad continuity such as rusty material or just something gets in the torch tip that will cause the torch touch to fail during the touch off cycle.

you can use the conductive torch touch in conjunction with the float switch (floating torch head) set up which will act like a back up to the conductive torch touch or use solely the Float head as the touch off.
Joey
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Re: Need an explanation of touch off

Post by Joey »

The Acorn can also be set up to use both Torch touch and a float switch in conjunction with each other. For example the Torch touch is the primary setting zero. But if the torch touch does not have good continuity thru the material to the material clamp during a touch off cycle, then the float switch will automatically take over and perform the touch off cycle via the float switch. Thus the majority of touch offs are using the more accurate way of setting zero but if the torch touch fails the float switch will override and insure a interruption free job. Another feature of Acorn Plasma is the auto air purge to clear water or debris from the torch tip. If the Torch tip is shorted internally during a Torch Touch, Touch of event, then Acorn plasma will purge air through the torch tip. If the debris do not clear during the purge and a secondary float switch is being used in conjunction, then the float switch will over ride and continue the touch off cycle.
TAS99
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Re: Need an explanation of touch off

Post by TAS99 »

Thanks for all the replies. I think I understand it now.

Tom
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