cylinder sizes

[jdcollector]

Howdy all. I'm new to welding and looking at purchasing a MM180. I am trying to figure out what size cylinder in need to purchase for my shielding gas. I keep hearing about k, t, p(?) size cylinders and have no idea how large or small they are. Is there a chart or reference sheet out there that tells me how many cubic feet these cylinders will hold? Also, what size would be best suited for this machine? I will be welding mostly old farm equipment and small fabrication projects. Thank you for the help.

[metalmeltr]

It depends on how often you use it.

[PipeLayer]

Like metalmeltr said, It depends on how much you use it, maybe this link will help. http://www.airweld.net/images/Cylindersizechart.gif

[Laiky]

You buy the biggest one that fits your needs. If i have to move them to the job often, i like 80CF, if i have to move them occasionally 125CF if i move them only for refill 330CF. The bigger the cylinder the less you pay per CF of refill. I pay 50 bucks for a 330 of argon and 37 for a 125.

[fabricator]

Around these parts a 125(the cubic feet it contains) is the biggest you can buy as your own. I use these for portable work. A 330 is the largest in compressed gas cylinders,and can only be leased. If you can buy A 330 from an individual or supplier get that or go with the 125.

[deafman]

If you plan on doing small projects or practice in the backyard I would go with an 80 cu ft. size. This size has a screw on cap. Smaller cylinders don't have a cap except some 60 cu ft cylinders. 60 cu ft is not a common size or may not even be available from your store or area. Some welding stores won't sell you a cylinder larger than 80 cu ft size but most will sell up to 125 cu ft size. The two sizes are the same diameter, 125cu ft. is just taller. For household use renting a cylinder may cost you quite a bit more over the long run. A full 80 cu ft. cylinder will probably be about $210 to $230 to buy. A refill may run about $35 to $40. Make sure that the welding store that you buy the cylinder from is convenient. Other welding stores may or may not exchange the empty cylinder for a full one. Airgas tends to be higher priced than the independant dealers, but is nationwide. If you move out of the area then try to sell the cylinder back to the dealer. Keep the original bill or title to the cylinder so you can prove ownership.
75% Argon/25% CO2 is common and allows easier welding on thin material. 100% CO2 can also be used for steel welding, but usually comes in older 330 cu ft size rental cylinders. Most of these have 50 pounds of CO2 in them. CO2 welding tends to be harsh and has a harder arc and more spatter.
Some welding stores will not load ANY cylinders into the trunk of a car while others will allow a small shielding gas cylinder to be loaded but will not do it themselves. Sometimes their policies vary by the salesman!

[Leons2003]

All my cylinders are purchased as refered to as "S" or 125cf of C25,Argon or "WS" or flat top for acetylene, original bottles were purchased from Linde yrs. ago at a dealer my wife worked at, since bought out by Airgas which those dudes are high on everthing. I now deal w/an independant. Latest bottle I've purchased is a CO² which was ~$235., personally I would not fool w/the tiny cyl. nor lease, I'm kinda in between a little work and a lot.
Good luck
L*S

[fun4now]

i used an 80 tank of C-25 for years. then some one pointed out to me that Co2 only causes splatter problems over 200amps. so i tried it and have used it exclusively ever sense. the Co2 tank is smaller than the 80 and lasts about 4X longer at 1/2 the price. so if its at all possible i recommend you try it out. and look into prices. biggest thing will be ask around about what sizes they will sell, and fill options.deafman has a good point about checking about possible loading issues.

another thought to consider is Co2 is said to be more tolerant of less then clean surfaces. with farm equipment in the work load, it may be a +.


having a tank of each would not be a bad thing. trust me when i say running out of gas in the middle of a weekend project is a real bummer.

[Tailshaft56]

Keep in mind you should be able to trade up your cylinder @ full value. Let's yoy start out for a few less bucks.

[fun4now]

Tailshaft56 makes an excellent point. you could start out with an 80 and move up to a 125 if you feel the need for a larger tank. i have a 125 and an 80. i don't think any larger than that would be the easiest to move around, much less transport in a car. this may not be an issue, but might be worth thinking about.