Weld time till bottles empty?

[RamblinMan]

Going to buy my own bottles for home use and wondering about size because money is an issue. Gonna buy 3 bottles Oxygen, Propolyne, and Argon. Im looking at 60 and 80cf size what I wanna know is how long approx could run either size bottle at say 30psi, 40psi, 15psi till i run it empty. So i can decide what size bottle from there. Thanks

[Meltedmetal]

I don't think anyone can give you a definitive answer. It depends on what you are doing. Argon might be easier. Divide the CFH you intend to use by the bottle capacity. Even that is dependent on what equipment you are using and what material you are welding. Cutting and heating with propylene is going to depend on what tips you intend to use and how effective you are with the torch and what you are working on. Its not cheap and if you use a lot usually larger bottles are more cost effective and involve less downtime.---Meltedmetal

[RamblinMan]

Thanks yeah I didnt figure their would be a definite answer. I just got outta welding school so all I really need my torch for is cutting weld coupons till I find a job. Then after that it will just be here and there for small tasks. Thanks for your input!

[ryanjones2150]

For me, I'd get the biggest bottles I could afford. You can always trade up later.

[Synchroman]

I don't know how to correlate psi on the round dial meters to standard cubic feet per hour. (SCFH) Obviously if you have a ball flow meter and are reading directly in SCFH, you can easily calculate, For example an 80 cu ft cylinder at 15 SCFH will give you approximately 3 plus hours of welding time. If you are practicing a lot, bigger is better.