Advices for my first Propane/Oxygen set up for fillet brazing a steelroad bike frame, Oxygen concentrator
Hi guys, I have been checking on various websites and youtube videos for all the necessary information for a proper Propane&Oxygen brazing set up, but I need the help of who has much more experience than me. I was thinking about propane because acetylane apparently is much worse for your safety and I'm not so sure if my insurance would cover it. The problem with propane, as far as I know is oxygen consumption (I've seen that the ratio of oxy/propane was around 4:1, but correct me if I'm wrong). Buying a 14L oxy-tank with a manometer here in Italy is around 220€ and refilling costs around 90€ (very expensive in the long run). To defeat this problem I've read in some framebuilding forums a few more experienced frame builders working with oxygen concentrators. The possibility to have preatty much unlimited oxygen is wonderfull and would make this hobby more financially bearable for me. So I did some research and I came upon a few issues:
- Do I need a 5 LPM or a 10 LPM oxygen concentrator? The big difference would be cost and availability. I found many 5 LPM O.C. used but in very good condition maybe at around 300€ on Ebay. The 10 LPM much much more expensive if I choose the medical brands (even more than 1200€), but at around 700€ from industrial suppliers of aquaculture equipment (but 2 months for shipping). What are your opinions on oxygen concentrators compared to oxygen tank set up? If you already have experiences with OC what are your advices and what information would you have loved to know beforehand buying those (like capability, purity, costs, ecc...)
- Tips sizes: I have no idea which size of torch tips I need. I already have a Oxyturbo Mini (Italian brand I think) as a torch handle. Some say a propane tip that goes at 100 liters per hour for the small tubes and braze-on, and 315 LPH for BB shell, but it seems there isn't really a objective thruth and is based on preferrence and habit. Which sizes do you advice me to buy that is really necessary at the beginning, but allows me to do everything.
- Tubes: are branded tubes really necessary?
- What kind of brazing goggles do I need?
- What size of propane tank is enough? I'm not so sure that the 4:1 oxygen/propane ratio is always true so based on what gas ratio u guys work with maybe I should invest in a bigger tank. What is the working gas proportion?
For now these are the main issues that came to my mind but I will ask more in the future. I hope you guys can give me some word of advice. I'm already looking at paul brodie youtube channel and some posts on bikeforum, but I still wanted some more precise information. Thank you for your time!