Drilling and brazing a fuel tank

If he's pointed the right direction you might not even need to have it delivered!!!

Anyone who cuts or welds on a container that has EVER contained gosoline or other flamables without taking adequate precautions is a fool and an idiot. And "adequate" does not mean "barely adequate", or "should be good enough".

Nope - it was gasoline vapour. Had it happen to a friend on his 50's ford tank. He'd flushed it with water, let it sit in the sun, and filled it with water again - stood it against the shop wall and started to braze it. It heaved and buckled and knocked him on his ass on the other side of the driveway. They figured out there was gasoline "locked in" to the rust where he was doing the repair - perhaps 1/10 of a teaspoonfull at the very most

- and when he heated it, the rust was reduced to iron and oxygen - which mixed with the gasoline with extremely un-expected and violent results.

DON'T DO IT.

If the tank had been full of CO2, Nitrogen, or Argon (I prefer CO2), the oxygen and gasoline vapours would have dissipated into the CO2, instead of being trapped and concentrated - and combustion would have been IMPOSSIBLE.

Trust me Iggy - it is STILL a potential bomb. What does a CO2 fire extinguisher refil cost????? Fill the tank with a shot of CO2 untill you see it flowing out the top (as a fog). Let it sit, filler up, for a moment, then add a bit more. Weld with filler up, and new fitting snugly in the hole, and plugged so the CO2 does not all flow out through the fitting as you weld/braze/solder.. If the job takes very long - give it another shot part way through - and you can GUARANTEE you will be here, and in one piece, the next day.. REmember, CO2 is almost twice as dense as air - but not NEARLY as dense as you if you weld that tank without taking "proper" precautions.

A garden hose from the exhaust is NOT going to do the job.

For cripes sake - BORROW a CO2 extinguisher if you are too cheap to buy one, and get it refilled when you are finished. Your ass is worth more than 10 bucks!!!!

PURGE WITH AN INERT SUBSTANCE - is the secret - and KEEP IT FULL. Water does not count. You want an inert substance that can absorb and dispurse any traces of fuel vapour, and any trace of oxygen in the tank.oducing a mixture that is too weak by an order of magnitude, to burn.

Water can't do this. CO2 can. Argon can. Even Nitrogen can. If using auto exhaust, you need a large (roughly 2 inch ) hose, a well warmed up and properly running engine, and several minutes of purge before starting to weld - with the exhaust still flowing.

BS. If you are CUTTING the mixture is extremely lean - high in Oxygen

- and if there is ANY fuel in the container, it is oxidized by the extra OXYGEN. There is NEVER any leftover acetelene during a cutting operation. You don't (can't) cut with a carburizing flame

snipped-for-privacy@snyder.on.ca fired this volley in news: snipped-for-privacy@4ax.com:

I believe that is pure BS. Sorry... I'm not impuning YOU, but the "solution" you describe was obviously mis-stated to you. It's garbage. If you cannot _smell_ gasoline fumes, they cannot form an explosive mixture.

I'm pretty clear on that matter, being involved in the "flammable chemicals" industry.

LLoyd

snipped-for-privacy@snyder.on.ca fired this volley in news: snipped-for-privacy@4ax.com:

Ibid, my last.

LLoyd

snipped-for-privacy@snyder.on.ca fired this volley in news: snipped-for-privacy@4ax.com:

You've never actually done this, have you Clare?

LLoyd

Lost count how many gas tanks I have repaired. Used exhaust for quite a few years - then started using CO2. Using a garden hose from an auto exhaust, most of the exhaust bypasses the hose unless you pack around it with rags etc. I used to just put the shop exhaust hose over the tailpipe, and connect it to the filler neck withthe tank unit out and let it run a few minutes,until the tank was warm - then start brazing (or soldering)

I've tried water too - but unless you are going to arc weld, there is way too much thermal mass.. With CO2, it is DEAD SIMPLE. And the repair can even be made on the car if the leak is not on the top of the tank, you can reach it to clean it, and there is nothing flamable too close to the tank.

A lot more than some dry ice that someone mentioned.

Dan

And a lot more than filing the tank with water from a garden hose.

Depends where you are. Getting dry ice in some areas is not nearly as SIMPLE... But yes, if available it will definitely work - and well.

Whicm may, or may not, be as safe.