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Should I get the 50I, the 60I or the 80I?

10-25-2010, 09:01 AM
I think that I would be happy with a 50I, but would I really? The Force Cut 60I can cut 7” per minute of 1 inch, and 17” per minute of ¾ inch steel. The Force Cut 80I can cut 7” per minute of 1.25 inch and 17 “ per minute of ¾ inch steel. For the $200 premium, is the 80I better? They look like the same box, one with 7000 Watts, and one with 9000 Watts. I normally cut 3/8 steel or less, and every once in a while some half inch (with a Lincoln Procut 25). Does anyone know if the 80I used at 30 Amperes, would last longer and/or work better than the 60I set at 30 Amperes?

I am of the opinion that most of my cutting requires 30Amperes, so 60 would be plenty, but for another $200, I can hit 1.25 inch plate;) Are the only benefits of the extra 20 Amperes speed of cut for less than 1” or 1.25” and max thickness or is there another reason to go for the extra power?

I was always told that Plasma was for cutting less than an inch thick steel, and a torch should be used after this. I am sort of leaning on the old time is money, so a cleaner cut at the same speed with less dross is making me what to spend more while the higher the amperage, the quicker the consumables wear out, and if I have it, I’ll use it;)

10-25-2010, 10:41 AM
I think that if you have the $$ I would go with the biger machine, you can always dial down..

10-25-2010, 03:06 PM
I went with the 80 for the 100% duty cycle at 60 amps. That was important for my CNC table. If you do any heavy cutting it would be worth going for the bigger unit.

10-25-2010, 05:23 PM
Gadget, if I’m hearing you correctly, if I think that a 60 is the sweet spot, then an 80 is 100% a 60;)

I think that I’ll sleep on that one.

Kel Fab Creations
10-25-2010, 05:35 PM
I am having this same dilemma but more toward the 50i and 60i. The thickest I ever cut is 1/4". I may need to cut some 3/8" down the road for some header flanges or something but that will be like 2 flanges and done. How much of a speed difference will I see on steel 1/4" and under? I'm gonna get the new machine torch that's rated at 80 amps so will I still see good results cutting thinner stuff at say 30 amps?

10-25-2010, 05:42 PM
For CNC I usually use 60 amps to allow for a faster cut speed. However, when cutting aluminum I cut the amperage to keep from melting some of the small detail. I could cut at lower amperage but would have to reduce the cut speed and would get more dross.

Kel Fab Creations
10-25-2010, 06:51 PM
So say u were cutting 1/8" steel at 60 amps. Do u get more warping, bigger kerf or more angle on the cut than u would at 35 amps?

10-25-2010, 07:04 PM
I think it all kind of balances out. With more amps you can cut faster but with more heat. Reduce the heat and go slower and the metal has more time to warm up. The kerf will remain pretty much the same, that's mostly determined by the tip of the cutter. The angle balances out too. Faster speeds means more angle, higher heat would reduce the angle. Of course, I'm no professional and this is just my opinion.

10-26-2010, 08:56 AM
The decision is a dilemma since I am a weekend warrior vs. a professional, so if the machine dies, I can wait for repairs.

My decision is made, the 80I wins hands down. I just hope that it is not a 60I with a larger heat sink;) I had a 25 Amp machine, and always wished I had paid a little more for the 55 Ampere machine. Then I looked at the 60 Ampere machines from various vendors and was amazed at the performance. I design electronics for a living, and know that most commercial machines are never derated properly. So Gadgets suggestion of getting an 80 and typically running at 60 is mark on. The derating of the internal parts of the machine mean life of product. When you run a machine at 80% of it rating it will last five times as long.

---------- Post added at 08:56 AM ---------- Previous post was at 08:50 AM ----------

I agree with Gadget. What I have noticed is that that the warping is less with more Amperes with steel since it takes steel a long time to transfer heat. If you can move fast, the heat zone is very small as the metal with direct heat is vaporized and blown away. With aluminum, this may not be the case since it is a good conductor of heat.