Home Made Forge made from Gas tank

As mentioned in my last instructable Fire extinguishers are amazing and mostly free. What we will be building today is a home made forge capable of melting stainless and we tried glass but it just went mushy.

Shopping list:
Gas tank empty (free)
Gas tank full (have)
Fire extinguishers (free)
Welder (have)

Step 1 Empty gas tank Clean Clean Clean

We attached our gas tank to a BBQ and burned off the last few minutes of gas tank.
Then put a regulator on hung it upside down and turned it on.
Drill small hole in top BE CAREFULL
Drill another hole in bottom

The tank will be quite full with gunk that smells really bad.
YOU MUST CLEAN BEFORE CUTTING.
To clean it out we then made these holes much bigger then put lots of boiling soapy water washing out threw the gas tank.

Comments

[liamdorman]

you mean aluminium... not stainless - right?

[namit]

Yup

[NovelUserName]

Good idea using old fire extinguishers for crucibles - I was going to weld mine out of a chunk of old pipe, but your solution sounds more elegant.

One question:
If the crucible is a steel fire extinguisher, why doesn't it melt at the same temp as your steel scrap? I see a lot of these setups used for Aluminum melting/casting, but since most people use a steel crucible, they can't melt steel. I'm just curious how you got yours to melt steel.

[rblenkinsop]

namit,
Good instructable & good idea.

I would be very careful cutting on any kind of tanks. You might find a local propane dealer that would either swap a bad tank with you or purge the one you have.

I have a close friend that was welding on a diesel truck fuel tank that got burned very badly several years ago. Yes, it was filled with water also, vented and cleaned thoroughly prior to welding on it but what I think happened is that the water displaced the fumes and concentrated them into an air pocket. Of course the end result was an explosion and him being physically hurt as well as burned very badly.

As you seem to be very sharp and you probably though of this, it may help to suggest this to others and / or as a friendly reminder as to what can happen.

I have a couple of these laying around and I'm going to build one before too long.

[namit]

Yes we mainly just made sure to drill small hole leave for a while then go bit bigger holes. Then wash out then wash out more. Once that was done was happy to cut it open.

Great please do post up on site.

[ironsmiter]

Also note, MANY fire extinguishers are made with aluminium shells, not steel like yours.

Just so people are aware... they may have a puddle of melt in their furnace instead of a crucible full ready to cast... if not careful in selecting material.

[namit]

Good to know all the ones we have opened where steel. Would be nice to have smaller wall on the melting pot.

[rimar2000]

Good idea, good instructable.