Pierce height is greatly dependant on type of pilot arc and the thickness of the material being cut, as a simple guide, the thicker the material the greater the distance between nozzle and material.
When that distance is to small, the material melted during piercing will inadvertently end up in the nozzle, thus melting small bits of it and quickly rendering that nozzle useless.
BigJohnT wrote: For some reason that I can't remember I have pierce height in my touch off subroutine. The Hypertherm 1250 manual does not mention pierce height anywhere, am I going nuts or did I find something at one time about pierce height that made me add that?
I've noticed some of the Hypertherm documents sometimes quote the pierce height as a percentage of cut height (eg 250% or something)
I am looking at the Powermax1250 manual right now.....at the top of the Mechanized cut charts it tells the torch to work distance for all cuts....right above the picture and part numbers of the consumables that are suggested for use. Make sure that you are looking at the mechanized cut charts....even if you are using a hand torch....as it is mechanized cutting. Make sure you are using the consumables listed, especially the mechanized shield, as it is quite different from the hand held (drag) shield.
For pierce height, always use at least twice the cutting height (that recomendation is in the Powermax1250 manual as well).
Your arc voltage setting as listed on the cut charts in the manual is a starting point only....get the rest of your parameters set up, and I suggest using the optimal speed settings for the best combination of quality and minimal dross, then adjust your arc voltage setting up or down until the recomended physical cut height is achieved......do not worry what the voltage setting is.
The cut height physical setting is only correct if you are using the exact consumable parts listed.
If you do not have the operators manual for your 1250 it can be downloaded for free from the Hypertherm | Plasma Cutters | Plasma Cutting Equipment | Metal Cutting Equipment website. Click on document download, choose the system, choose operator manual, and you can get a .pdf or a zip file download.
Jim Colt Hypertherm
Well there you go... but I can't find that in my 1250 manual cut charts however I did find another setup manual for the 65/85 that lists pierce height.
I often use Hypertherm Xnet. That is a system that provides all the documentation for OEM.
Can i help you with a certain document?
Attached the 105 powermax user book. This is the most useful book for the series up to 105 amp's include's also your older pm1250 inverter because of the same duramax torch serie's.
we.tl/t-OnNgfBCziR ( link works one week )
Have fun !!