First cut.

[Shield Arc]

All this talk about using propane to cut / burn with. I got to thinking, I haven't burned with propane since the mid 1980s. Worked on a joint venture with another company, they were the prime, so we used most of their equipment. Anyway, 1/2-inch thick flatbar, # 2 propane tip in my Victor torch. 10-pounds of propane, 40-pounds of oxygen. Not to bad, being as I can't even remember the last time I used a torch.

 

[yomax4]

With Cuts like that, You may as well sell me the Ellis 1800. Nice work.

 

[Shield Arc]

Thank you! Yeah that Ellis is one sweet saw, I don't envision that saw going anywhere.


I remember now, the last time I used a torch was a couple years ago when I revamped the grapple to fit my tractor. I used the plasma to cut slots in the bottom, but used the O/A torch to cut the circles in the sides to help lighten it up.

 

[Big Wave D]

What's your personal verdict?

 

[Shield Arc]

I'm not a real fan of propane, but maybe because I'm a creature of habit. That joint venture I was talking about, I was rigging full time, but got elected to go in on a Saturday to build a unit for a crane. So in my life time I have that Saturday, and this cut using propane! It's OK, nothing in the world wrong with it. If I had to throw any stones, I'd say it is just a touch slower than acetylene, but not by much. Well worth it for the difference in cost between propane and acetylene! :thumbsup:

 

[Big Wave D]

Curiosity, then why would you have had any propane cutting tips for your own torch equipment?

 

[Tractor Seabee]

I have never used propane, but used a natural gas/O2 torch when working in a fab shop. They had the propane piped all over, moved an O2 tank around on a cart and just plugged in. Far superior cutting than Acetelene. Even manual cuts were clean and no slag to clean off. Did not even have to hit with a grinder even on a bevel cut. I think I will check on getting the tips and set my cart up for both gases if it works. I do a lot of OA welding on thin stuff or if I want to do a one pass job like that thread on the propane tank/roller conversion. Also do brazing both bronze and silver and soldering of copper; so, propane works for that also. Acetelene is getting priced out of sight with the low volume demand, due to these other new proceses on the market. Used MAPP gas once but was unimpressed, it has gone away also now, I guess.

Back in the 90s a company came out with a torch system using gasoline and O2. The demonstrations were awsome to watch. No slag and no heat below the cut. They had a lady put her bare hand 12" below the cut and all she got was some fine black ash. Very claen cuts also. It never caught on or was not accepted by the safety police so do not see anymore. Always wanted to try it but never worked any where where it became a tool.

I am still a O/A fan as I am better at it than arc. Grew up on O/A welding of steel piping systems up to 6".

Time marches on!!

Ron

 

[eastexan]

I have never used propane, but used a natural gas/O2 torch when working in a fab shop. They had the propane piped all over, moved an O2 tank around on a cart and just plugged in. Far superior cutting than Acetelene. Even manual cuts were clean and no slag to clean off. Did not even have to hit with a grinder even on a bevel cut. I think I will check on getting the tips and set my cart up for both gases if it works. I do a lot of OA welding on thin stuff or if I want to do a one pass job like that thread on the propane tank/roller conversion. Also do brazing both bronze and silver and soldering of copper; so, propane works for that also. Acetelene is getting priced out of sight with the low volume demand, due to these other new proceses on the market. Used MAPP gas once but was unimpressed, it has gone away also now, I guess.

Back in the 90s a company came out with a torch system using gasoline and O2. The demonstrations were awsome to watch. No slag and no heat below the cut. They had a lady put her bare hand 12" below the cut and all she got was some fine black ash. Very claen cuts also. It never caught on or was not accepted by the safety police so do not see anymore. Always wanted to try it but never worked any where where it became a tool.

I am still a O/A fan as I am better at it than arc. Grew up on O/A welding of steel piping systems up to 6".

Time marches on!!

Ron

You may be correct, but what I understood as to the rise of acetylene prices was due to the high demand and the lack of supply because one of the main factories in the US had an accident and had to close. As to it opening back up again, I haven't heard.

Right now, some or most of it has to be imported.
I've heard that the price is beginning to come down a little.

 

[Shield Arc]

Curiosity, then why would you have had any propane cutting tips for your own torch equipment?

My acetylene bottle is getting low, I figured a $7.00 tip was cheaper than having my bottle filled.

 

[rhett]

My acetylene bottle is getting low, I figured a $7.00 tip was cheaper than having my bottle filled.

lol, got myself a small set of LP/NG tips (000, 00, 0 & a 1) and still need to refill the Acetylene bottle. burning with LP has been awhile for me too, but the smell of cutting with it, I cannot forget, kind of a sharp odor.

i have made a Propane Rosebud Cup for my Acetylene Rosebud to give LP a try with it. the idea was originally from "farmall" over at WW, great idea to help in reducing flame outs and the need for a large Acetylene bottle.

 

[Big Wave D]

My acetylene bottle is getting low, I figured a $7.00 tip was cheaper than having my bottle filled.

Now that, I understand. :thumbsup:

 

[Big Wave D]

To anyone with a plasma cutter, how much cutting does $7 worth of electricity get you? (Probably a rather tough thing to quantify. Guess-timates are fine. )

 

[dynasim]

The following is a quick(conservative) energy analysis for a plasma cutter cost. It does not include the cost of tip consumables. I think it is right, but others should check.

Amp Load 20A Compressor+Cutter
Voltage Supply 220 V
Elec. Rate 0.1 $/KVAHr(~KWhr)
Power Cost 0.44 $/hr Power Cost= V X A / 1000 X Price

Cut Speed 5 in/min
Cut Cost 0.00147 $/inch
Cut Cost 0.147 cents/inch

Chris

 

[deereman75]

The following is a quick(conservative) energy analysis for a plasma cutter cost. It does not include the cost of tip consumables. I think it is right, but others should check.

Amp Load 20A Compressor+Cutter
Voltage Supply 220 V
Elec. Rate 0.1 $/KVAHr(~KWhr)
Power Cost 0.44 $/hr Power Cost= V X A / 1000 X Price

Cut Speed 5 in/min
Cut Cost 0.00147 $/inch
Cut Cost 0.147 cents/inch

Chris

One issue I see is the amp draw. Just my 220v compressor alone draws 17 amps, the least I see for any plasma is 15 amp draw, so I would have calculated it for atleast 30 amps, if not 40.

 

[dynasim]

My compressor pulls about 8-10 amps at 120 V, and only runs about 30% of the time. I haven't run for really long periods, though.

Chris

 

[dynasim]

I haven't run my plasma cutter(for long periods of time), but the stated air consumption rate for my machine is 3.5 cfm.

The Everlast pp50 uses 31 amps at 220V at maximum power. I have only run mine at half power.

30-40 amps all in may be a better number. The 5 in/min was where I had put padding. I have cut a 6 foot square tube lengthwise(1/8" thick) in about 1-2 minutes per side(cleanly). That comes to 35-72 inches per minute. That is why I haven't run the plasma for long periods of time.

Chris

 

[yomax4]

If the 0.147 is correct, It's still worth it and probably similar to oxy fuel but you get to cut Cast, Stainless, Aluminum, Rust, Grease, Paint, Glass etc with Plasma. I find that you need a similar sized breaker for the output of the Plasma but they do build some of their own power. 80 amp Plasma likes an 80 amp breaker.

 

[deereman75]

My compressor pulls about 8-10 amps at 120 V, and only runs about 30% of the time. I haven't run for really long periods, though.

Chris

I guess I forgot how little air a plasma draws. I was just doing some sandblasting yesterday, so my mind was kind of on almost constant run. Gotta love a big air compressor.

 

[Big Wave D]

How does the price/inch of plasma compare to the use of O/A for cutting per inch?

 

[dynasim]

Here is Hypertherm's take on variable cost:

https://www.hypertherm.com/en/pdfs/PMX1650OperatingCost.pdf

Note that this is by a manufacturer of plasma cutters. Also note that the consumable(tip) cost is more than the electricity cost. The plasma that they are using for comparison must be significantly bigger than mine.

Chris

The root link:
https://www.hypertherm.com/en/Training_and_Education/Plasma_or_Oxyfuel/lower_cost_per_part.jsp