Welding gas advice needed

**cropwell** · 23-04-2019

I have a little Walkover set for light brazing/welding, but it costs a lot to run. The disposable Oxygen canisters cost £30 and last about 20 minutes. The fuel gas costs the same but lasts 2 to 4 times longer. For the price of 6 cans of Oxy, I can get an oxygen concentrator and refillable 2L cylinders of propylene are £26 a fill. So that seems a good way to go. One Google group making bike frames, report success with an oxycon and propane for brazing. As I have a cylinder of propane already, that may be the way I go. I have discounted acetylene for safety reasons.

Oxy/acetylene gives a flame of (up to) 3500C and Oxy/propylene 2900C, Oxy/propane 1900C. I can't find any figures for MAPP gas or equivalents like MAP-X or Turbogas. (MAPP is now not available anyway).

I would welcome advice, before I spend on an oxycon http://tuffnellglass.com/contents/en...centrator.html

Cheers,

Rob-T

**magicniner** · 23-04-2019

What are your primary applications?
I MIG braze some things, if it's decent weather I sometimes use a Carbon Arc Torch out doors.
I've had excellent results with Resistance Brazing using a single phase spot welder and modified electrodes.

**cropwell** · 23-04-2019

Originally Posted by magicniner

What are your primary applications?

That is a difficult one to answer. I do all sorts of little jobs, the last one was for a glassblower, who wanted stands for sculptures. It looked a bit like a laboratory stand (https://www.stuartakroydglass.com/intention/). The stands had to be chrome plated, so they were brazed and fettled. They were supposed to be ready for the BCTF in Harrogate, but the platers let us down.

Really I want something hot but delicate (?) for soldering, brazing and small welding. I have the MIG for the more brutal work.
I retired early, in 1999, and now only take on jobs to keep me active and interested. I am a bit of a Grandpa-fix-it to the family.

So, I can't really justify a big spend on kit that I will only use occasionally.

Cheers,

Rob-T

**magicniner** · 23-04-2019

A good MIG is delicate and adaptable, I braze 0.5mm sheet steel and thinner with mine.

**Dell** · 30-11-2019

Hi
I just thought I would give my thoughts I have a portapak not that expensive to refill lasts very well and very controllable, I mainly gas weld aluminium sheet but I also silver solder, braze and steel.
Dell

**Voicecoil** · 30-11-2019

I love my TIG welder - you can weld most things with greater precision and control than either MIG or flame, and it seems to be pretty good for brazing too.

**Colin Barron** · 03-12-2019

Tig is the safe way to go and gas is cheap. I rebuilt a MIG welder a while ago and paid a deposit on the bottle (from memory £80) and all you pay in future is for the refill (maybe £40). The little disposables cost a fortune and did not seal as well as a proper bottle and gauge,

**Neale** · 03-12-2019

I've seen some great examples of TIG welding and brazing on small objects (which is what I'm interested in) but looking around, a TIG welder would cost anything from £150 to several £K - and how do you know where the sweet spot is in that range for a particular job? I'm sure the cheap ones are too cheap, but then you rapidly get to the point where the ongoing cost of gas and other materials is rather irrelevant compared to buying the kit! At the moment I use MIG (a little) and often just to tack together CNC-cut tab-and-slot steel components that are then silver-soldered using a simple propane torch. I'm wondering about going oxy-propane which would be fine for brazing and silver-soldering but just not hot enough for welding (as I understand it).

Comments on TIG welcome - although I think it's going off the original topic more than a little...

**cropwell** · 03-12-2019

I would like a TIG welder, but I am afraid my workshop days are dwindling and I would never get any real use out of it. So I will stick with my MIG. Oxy/Propylene seems to be gaining favour industrially. Propylene gas is much safer than acetylene to store and use, but getting hold of it in small bottles is difficult. I have only found one supplier in Chesterfield. If I went the oxygen concentrator route, then I would probably use the Novacet cans with my Walkover torch, as they seem to last a long time compared to the disposable oxygen bottles.

The problem doesn't need to be resolved until September-ish 2020 when my Glassblower friend retires. Until then I can use his oxy/propane torch for small brazing jobs.

Cheers,

Rob-T