The consumables are easier to calculate for the oxy-acetylene just look at you gas card for the tip size and pressure and it will give you the flow rate.

starbolin, that was a good idea. I just looked at port-a-torch manual
online, that 20cf oxygen cylinder it comes with will only last me half-
hour cutting 1/8".

John, 42etus, thanks for heads up on Plasma. I debated with plasma
before and did some more research today. It looks like a good way to
quickly cut 1/4 and under metal plates with good precision, good
finish, low head distortion and low consumables cost. For the amount
of cutting and fabrication I do, to justify the cost of $400 Homier
Speedway 30Amp plasma cutter I'd have to spread it over 10-15 years
time frame, but inverters based welders/cutters are evolving so
rapidly - I think they are following consumer electronics/PC pricing
- performance doubles every few years while unit prices drops
(correct me if I'm wrong). So now I'm thinking, may be I should wait
till HF starts running $99 plasma specials, wishful thinking?
Another downside to plasma - poor portability due to 220V / air. And
the air compress that I got is NOISY. By the way, I found following
specs for plasma cutting speeds: 40 Amp - 17" Per minute @ 3/8" Thick
Steel. 12 Amps - 18ga./60 inch PM 10ga./12 inch PM 1/8 inch/9 inch PM

Mark - what you report on the circular saw is encouraging. So abrasive
disk with circular saw is the way to do it on the cheap. Is it better
then recip saw/sawzall? Do you have an idea how fast it will cut 1/16
metal or 12 gauge metal as far as feet /inches per minute go? I can't
find this information anywhere!

PS. Looks like I'll be returning 4*6 bandsaw to harbor freight for
refund, I haven't unpacked it yet. Just got it last week. Do I get it
right, that it's mainly for production work cutting tubbing/ angle
iron to length and it's slow and will not cut sheet metal due to 3
teeth on the work requirement - at 22TPI that makes 3/16" minimal
thickness. Thanks. Ross