Trying to cut 3/4" thick with Powermax65

[Metriccar]

I am trying to cut 3/4" steel with my Powermax65. It pierces fine, but it seems to keep getting hung up or trying to dive into the metal instead of cutting. It's a Plasmacam.

It will pierce the metal, then start moving like it's getting hung up. I cannot tell what it's doing. I can tell you there is a good deal of slag around the hole though, so not sure if that's causing it to get hung up.

When I pull the plate off there is a hole all the way through the metal with a bunch of slag around it.

[Shane Warnick]

More than likely you are running into the puddle from the pierce and / or are junking the nozzle at the same time. If the nozzle gets a bunch of slag on it during the pierce it won't cut anywhere close to right, and the arc density sucks so it won't really cut all the way through as it starts to move and it either loses arc transfer or dives the torch since the resistance is off. 2 things you can do, either do all the pierces, go back and change nozzles and shields AND THEN clean all the slag puddles and crumbs off from the pierce, or drill a hole with a mag drill and edge start. I use a mag drill on anything thicker than 1/2" it's way faster and cheaper and more consistent in the long run.

FWIW I have a samson 5x10 and am using DE with the software upgrades.


Shane

[jimcolt]

The Powermax65 has a maximum pierce rating of 5/8", if you are piercing 3/4" I suspect you are blowing material back on the shield and nozzle....and damaging the orifice. There are no specs for piercing above 5/8" in your operators manual as far as pierce height, pierce delay time....which are extremely critical.

If you insist on piercing 3/4" with the 65....I suggest using an old nozzle and shield....and doing all of your pierces only. Then change to a good nozzle and shield and start your cutting on the pierce holes.....this is like edge starting and will not hurt the consumables. If you use this technique you can also knock off the excessive top dross before continuing your cuts.

Jim Colt Hypertherm

[tnbndr]

If you are using Sheetcam look into setting up a wiggle pierce. I use it on 1/2" with my PM 45 and it works.
It is an option on the right side when setting up your tools in Sheetcam.

[hcweld]

Dumb guy question...What does the wiggle lead in do?

[tnbndr]

Instead of sitting in one spot and blowing molten metal the torch moves around "wiggles". You can set the size of the wiggle in the tool setup.

[jimcolt]

Wiggle lead ins will not help pierce materials thicker than the torch has the ability to pierce. You will still experience very short nozzle and shield life.....the orifices will be damaged to the point that cut edge angularity and dross are very bad.

Jim Colt Hypertherm

[Stout]

I have decided that my PM1250 will no longer be cutting 3/4" mild steel. It is just too hard on the machine. Between damaged nozzles, destroyed shields, melted insulators, and now a melted mounting sleeve, I don't think I'm making enough money to risk more damage. Not to mention the amount of blow out molten steel all over the place. I was pre piercing at +3 seconds and then cleaning the top dross before starting to cut. Just too much time and money wasted. Of course, the PM1250 is not rated to pierce 3/4", but it will do it. Just not here anymore.

Strange how it just rips right through 5/8". Pierce in less than 1 second and great cuts. That extra 1/8" is just too much.

[Larry83301]

If there are no holes in the part you could try starting off the edge of the material and making one continuous cut around many parts. If one or two holes are required you could setup a fixture on a drill press and just put them in that way.

Larry

[jimcolt]

Stout,

The Powermax1250 with it's original (G3) torch was rated at 5/8" for piercing as well. If you upgrade it to the Duramax torch....and follow the pierce specs from the Duramax operators manual (Pierce height, pierce delay, 80 amp shielded consumables) then it will have 3/4" piercing capability.

Jim Colt Hypertherm

I have decided that my PM1250 will no longer be cutting 3/4" mild steel. It is just too hard on the machine. Between damaged nozzles, destroyed shields, melted insulators, and now a melted mounting sleeve, I don't think I'm making enough money to risk more damage. Not to mention the amount of blow out molten steel all over the place. I was pre piercing at +3 seconds and then cleaning the top dross before starting to cut. Just too much time and money wasted. Of course, the PM1250 is not rated to pierce 3/4", but it will do it. Just not here anymore.

Strange how it just rips right through 5/8". Pierce in less than 1 second and great cuts. That extra 1/8" is just too much.

[jimcolt]

Or....you can read post 3 in this thread......piece all pierce holes with an old set of consumables (yes, the Powermax65 will do this), then switch to new consumables and cut your part file starting on the pierced holes. I have done this many times in the past with good success.

Jim Colt

If there are no holes in the part you could try starting off the edge of the material and making one continuous cut around many parts. If one or two holes are required you could setup a fixture on a drill press and just put them in that way.

Larry

[Stout]

Stout,

The Powermax1250 with it's original (G3) torch was rated at 5/8" for piercing as well. If you upgrade it to the Duramax torch....and follow the pierce specs from the Duramax operators manual (Pierce height, pierce delay, 80 amp shielded consumables) then it will have 3/4" piercing capability.

Jim Colt Hypertherm

I do have the Duramax MRT and those are the results.

[Stout]

Stout,

The Powermax1250 with it's original (G3) torch was rated at 5/8" for piercing as well. If you upgrade it to the Duramax torch....and follow the pierce specs from the Duramax operators manual (Pierce height, pierce delay, 80 amp shielded consumables) then it will have 3/4" piercing capability.

Jim Colt Hypertherm

Well it seems I cannot escape the .750 mild steel jobs.

Jim,
I looked at the MRT cut chart for the DM torch on my PM1250 and there is no pierce time specified for .750 and 80 amps. Can you point me in the proper direction?

[jimcolt]

I stand corrected...the Duramax torch is factory spec'd to pierce 5/8" when operated at 80 amps. You can pierce 3/4" by using a .24" pierce height and a 1.25 second pierce delay time.

Jim Colt Hypertherm

[HammerDownJustin]

My Hypertherm 65 pierces 1" just fine. Anytime I am cutting half inch or thicker I turn off my thc and it seems to do great.This piece was straight off the table with no clean up.

[HammerDownJustin]

145 volts
kerf .093
8 ipm
pierce delay 2.8
pierce height .37
plunge 8 ipm
cut height .06
pause at end 2 sc

Have no clue if it is close to what the numbers should be. Just made them up and it seemed to cut well. I dont cut 1" very often just for myself.