Hypertherm users: better fine cuts with 30A tips, or Finecut?

[motoguy]

I've got a PM85, which is just getting fired up. I've got the Finecut tips (as well as regular 45A tips), which I'm going to use on some thin material (22, I think some 24 gauge). I have a friend that builds race cars, and we're going to see what the machine will do on the metal he uses to skin the cars (some steel, some AL). I'm curious...the manual for my PM85 states it does steel down to 26ga with the finecut tips @40A. Though I can't pinpoint the post, I recall reading of people using the 30A tips on their machined to get better thin-material cut quality at lower amperage. The main issue seems to be the Ohmic situation, as the 30A tips don't have the Ohmic shield. That's my understanding.

So, my question is...when would you use the 30A tip as opposed to the Finecut? On material that thin, it seems that Ohmic would be even more necessary. I guess a secondary/stand off type post could be added for Ohmic use on the 30A. I'm just trying to figure out why these 30A tips were used instead of the Finecut.

[Brand X]

What 30 amp Nozzles? Never heard of one for the 85/65 machines.. It would be nice though..

[motoguy]

Gotcha. So I misunderstood, and these were PM45 owners having this conversation?

[Brand X]

Yes..

I still think low amp nozzles would be a great option for the 85, and 65. Keep you from running so dang fast with the best arc density possible. Shoot. some very high end machines have 30 amp nozzles, so that says something right there.

http://victortechnologies.com/IM_Upload ... mables.pdf

[steel 35]

Jim has talked about dropping the amp's that low using the fine cut consumables.

[acourtjester]

I use the fine cut nozzel on my PM65 machine torch and set the unit to 35 amps to cut 18 Ga and 16 Ga and use the fine tip shield with the ohmic sensor.
you can do the same with the PM85. Book shows 30 amps for 26 to 20 Ga low speed cutting and 40 amps for higher speeds
fine tip nozzel 220930
fine tip shield 220948 and retaining cap 220953 for u attaching the ohmic sensor wire to.
I had a slight learning curve but I am very happy with the cuts I am getting now. Reduce the pierce to 0.090" cut still at 0.060" I think Jim uses a lightly higher cut height for thin metal. Another thing posted here was adding a switch to have the arc OK signal on all the time for reducing the start divots on thin metal.

[Brand X]

Jim has also talked about Hypertherm bringing out low amp nozzles for the 85, and 65 amp machines. There is performance to be had ..I used the Esab PT-37 with the 20/30 amp nozzles, and it brings the the low amp cutting to another level. Yes you can run the larger orifice of the 30/40 amp nozzles, but I will take the 20-30 amp nozzles every time for art type sheet-metal.. I am talking cutting 0.035 Ms without water, and very little burn off.. 25 amps is sweet.. You would probably get less divot if you cut close to the same height as the Peirce. Even better then a switch will do.. (IMO) Of course I am using a switch on my current machine, but Tom's Arc good probe was a excellent system on Arc OK timing..

[littlefatbuddy]

I have a PM65 and run Finecut at 20amps for 20 and 24 gauge. I cut 14 gauge at 40 amps. I still use the .06 cut height. As long as my file doesn't have too many nodes it cuts really great. But that is a table problem for me not the cutters fault.

[HammerDownJustin]

I have a PM65 and run Finecut at 20amps for 20 and 24 gauge. I cut 14 gauge at 40 amps. I still use the .06 cut height. As long as my file doesn't have too many nodes it cuts really great. But that is a table problem for me not the cutters fault.

Curious how many ipm are you runing when cutting 14g at 40 amps instead of 45 amps?

[littlefatbuddy]

I set the speed at 225 ipm. I have a burnedtable so I am not sure how accurate that is. Also I have never been able to make the THC work so I cut a little slower.