Anyone ever gas weld without flame arrestors?

[5030]

Lets just say that I started out gas welding using metal coat hangers for filler rod. One thing I will say about starting out with gas welding is it's a very nice precursor to TIG because it teaches you 2 handed manipulation which is absolutely necessary with TIG. Only difference with TIG is the filler rod must be kept in the gas envelope at all times. I went from gas to TIG and had very little issue. While I use pulsed MIG today mostly, MIG is limited in what you can weld while with TIG (and the correct filler rod) you can weld anything that conducts electricity.

Some of the stuff I stuck together with coat hangers is still being used today.

 

[fishdrivel]

I started welding in 1960's. We never had flash arestors. I started seeing them while overseeing construction for the military.
As part of my job, I made sure contractors were using them.
Most safety features are a reaction to something bad that happened!

Here is a link to AWS standard, which is incorporated into OSHA by reference: https://app.aws.org/technical/facts/fact-28.pdf

 

[5030]

So long as you turn off the gas in the correct order, no chance of flashback up the acetylene hose. Flashback arrestors are like everything else safety related for the most part), protecting yourself from yourself.

Common sense always prevails if you have any.

 

[fishdrivel]

So long as you turn off the gas in the correct order, no chance of flashback up the acetylene hose. Flashback arrestors are like everything else safety related for the most part), protecting yourself from yourself.

Common sense always prevails if you have any.

Actually, If you run low on one of the gasses, you can backflow, mixing the gasses in the lines or even farther up. This can be a explosion hazard. Be sure an check your tanks and make sure you have enough gas to finish project.

 

[5030]

I own my tanks and get them refilled, I never exchange and I never run them totally out, especially the dissolved acetylene.

 

[etpm]

I own my tanks and get them refilled, I never exchange and I never run them totally out, especially the dissolved acetylene.

I own my tanks too, all 8 of them. I always exchange them. That way I don't have to have them hydrotested. I just keep exchanging cylinders. Where I live in WA state I'm not even sure I could drop my cylinders off and then pick the same cylinders up later if I wanted to. 52 years ago in CA state I could though. I could even wait sometimes while the oxygen cylinder was filled but never the acetylene cylinder because they were all filled in a different plant. Just curious, why do you never exchange your cylinders? Is it because you think you might get contaminated gas? This has happened to me a couple times but I have been exchanging gas cylinders for nearly 40 years. I don't know how many exchanges that equates to but it's too many to count.
Eric

 

[5030]

Hydro test is only once every 10 years and my Air Gas compressor station does it for 5 bucks, not a big deal. Not sure how many bottles (they aren't tanks, they are bottles) I own but around that number.

I have a thing about exchange bottles, they usually look like they went through a war. All mine are nicely painted and have my company name on them, just the way I prefer it.

Your preference may be different. No issue with me.

 

[etpm]

Hydro test is only once every 10 years and my Air Gas compressor station does it for 5 bucks, not a big deal. Not sure how many bottles (they aren't tanks, they are bottles) I own but around that number.

I have a thing about exchange bottles, they usually look like they went through a war. All mine are nicely painted and have my company name on them, just the way I prefer it.

Your preference may be different. No issue with me.

Hydro here for gas cylinders, AKA bottles, but not tanks, is 50 bucks for acetylene, and has just been changed to 7 years here in WA. Argon and other high pressure gas bottles have cheaper hydro fees and a longer interval than acetylene cylinders.

 

[etpm]

Hydro here for gas cylinders, AKA bottles, but not tanks, is 50 bucks for acetylene, and has just been changed to 7 years here in WA. Argon and other high pressure gas bottles have cheaper hydro fees and a longer interval than acetylene cylinders.

It looks like the DOT only requires requalification of acetylene cylinders every 10 years. But the two places I exchange at require 7 year intervals. Now I'm curious about what's really going on.
Eric

 

[rScotty]

Cool, thanks! I'll incorporate all that information into whatever plan I come up with.

What I'm hearing more than anything is I'd better *make sure* I have enough brazing rod on hand so I don't have to run to the store while the thing is hot.

Thanks again!

Most brazing is done with Low Fuming Brass (LFB) and with the base metal - usually steel or iron - heated to just before it becomes dull red. Brazing is a good technique and worth learning.

Since brazing doesn't take as much heat as welding, you can fix things like broken cutting tools just by keeping the cutting edge cooled off to save the temper.

When you go to the shop, you may find that your welding shop carries some other brazing alloys such as silicon bronze or "nickle-silver" rod. Sometimes you have to ask because they may be in one pound packets.

Buy a few and Give them a try. 3/32 to 1/8" are good sizes. Get bare rod rather than flux coated. You'll learn faster by adding flux to the joint by hand.

The silicon bronze rod works just like LFB but seems to me to be a little better just about everywhere I've used it.
And the nickle-silver rod is even stronger. Ignore the silver in the name, it doesn't contain any silver - but it does cost more than other brazing alloys. I find that it is a whole lot better at wetting out and for flowing - particularly on cast and forgings. It makes Noticibly stronger joints
There are special fluxes, but I use the same LFB flux for them all.
rScotty

Oh...BTW, I've used torches for over 50 years now and never have used flame arresters/back flow preventers.
I think they are a good idea, but not having them wouldn't worry me. If it bothers you, put your tanks around the corner from where you are working.