Oxy/acet torch question from rec.crafts.metalworking

"SteveB" wrote in news: snipped-for-privacy@news.infowest.com:

Think of it as a "negative" lottery.

If you weld A LOT or are a moron, you DO NOT want to "win". Flashback arrestors will prevent you from "winning".

If you don't weld much and are reasonably intelligent, you will probably not create situations that can cause flashback.

Having said this, I use them anyway. It would be too embarrassing to blow myself up because I didn't use them.

I can't see this post. Is it only me?? Can you repost? Thanks! Andrew.

If you use O/A - can you please tell me how long you've used it for, if you've ever had an accident and if you endorse or actually physically support the use of backflow preventers/arresters?? Do you think that an arrester is better at the torch or reg? I figured if the line caught fire, I'd want it at the reg to avoid the tank going up in flames. Thoughts? Do you wear a mask when O/A welding??

I have a victor torch and to my knowledge it isn't the one that has the flashback arresters built in. Although, I'm going to run to check for sure as I was shown at PraxAir (local welding supply house) what to look for.

Thanks for any and all help! Andrew.

If there's any interest, this article seems to offer some decent insight:

Andrew.

I use them at the regulator just for peace of mind. I don't wear a mask, but proper PPE (personal protective equipment) FOR ANY WELDING is vital. Proper shade, gloves, long sleeve heavy cotton shirt ( I like khaki Wranglers ) cap to protect what hair I got left, and ear plugs. Hot sparks in the ears from welding can cause big big problems. I also like to use shaded full face shields as my eyes don't sweat like they do in goggles. Plus I wear glasses, and they fit over glasses and provide protection for them.

HTH

Steve

Most modern torches have back-check valves built in. Some have flashback arrestors built in. Harrold, who owns Hansen and Miller, says he hates the torches with arrestors built in because they tend to get clogged with soot. He recommends backcheck valves on the torch and arrestors on the regulator. You may lose a hose, but the regulator would be safe. That is what I have at school on all our torch sets.

an interesting story for you.

was at the oshkosh airshow attending a seminar on O/A welding. during the lecture portion the speaker heavily stressed the use of arrestors, showing many regulators and hoses that failed.

then he went to show us how to properly turn on a O/A rig using his personal gear. I shot up my hand and asked him to point out the arrestors.

there weren't any.

Priceless.

Thanks for the reply. I ended up picking up some flashback arresters for $50 worth of peace of mind. I welded my first O/A exhaust system and it isn't absolutely terrible. My largest problem getting going was full comprehension of the neutral flame. I was running a carbon-laiden acetelyne rich flame that was lacing all my work with soot and causing poor joints. It really is an artform. I imagine that after maybe 10 more projects I will be much more dialed in. I'm reluctant to feel too secure doing O/A welding on my back just yet but I'm getting more comfortable as we go.

Thanks again for all your support. Andrew.

I guess it's a simple case of 'do as I say not as I do'.... When teaching safety though this is a little silly and somewhat unacceptable as an oversight IMO.

Andrew.