View Full Version : Welding Sheet Metal with a HH175
I need to make a little fuel tank about the size of a shoebox for an old tractor, any tips on what gauge metal would be easiest to work with? The welder is setup with .030 and 75/25 gas, should I use smaller .023 wire? and will that require a new liner?
Also been thinking about what to use for a threaded cap and base, the old cap and base are galvanized and I'd rather not mess with them. I think for the bung on the bottom I'll just use a 1/8 x1 x1 and then drill and tap it. This will be my first ever at sheet metal, I plan on buying extra for practice :)
09-24-2002, 12:57 PM
Wire size used depends on thickness of metal your welding. I would use 16 or 18 ga. steel. You should be able to weld that with your .030 wire. To use thinner wire just change your contact tip to propper size and flip the drive roller to small groove. Don't bother changing linner as yours will work ok.
This is going to be a hard project as your welds will have to be near perfect to not leak fuel with good weld stops and starts.
Weld on a pipe coupling or pipe nipple for outlet. Could use 1.5" pipe nipple cut to fit tank for fill fitting with pipe cap having small hole for vent.
I would rather braze or solder such a project.
You might consider starting with something like a surplus 45-cal ammo case and weld it closed or weld on a new lid.
There are still some things sold in 1-gal metal containers (water sealer, paint thinner,etc) NOT TO BE WELDED, but use the screw lid as is and either a gasketed or soldered (with soldering iron) exit fitting.
As "first ever sheet metal" project, doing a tank from scratch is pretty challenging ... but it is still OK to buy some and practice ... you might be a natural at it.
09-24-2002, 10:54 PM
Great idea using ammo case. Thick metal and minimal welds to use as fuel tank.
I found ammo can under a pier about 25' sea water depth (11 PSI) full of lead weights and still dry inside.
Hobart Expert Rock
09-25-2002, 07:48 AM
HI ALAN........I THINK ROGER AND ALAN HAVE A GOOD IDEA THERE. WHEN DUCK HUNTING I USE A AMMO CAN AND THE AMUNITION NEVER GETS WET FROM RAIN OR WATER............ BUT I THINK YOU CAN STILL GRAB SOME THIN GAUGE MATERIAL AND HAVE FUN WELDING IT UP.................CHANCES ARE YOU MIGHT LIKE YOUR PROJECT BETTER THAN THEIR SUGGESTIONS...........JUST MY 2 CENTS WORTH. WHAT EVER YOU DO BE SAFE.............AND HAVE SOME FUN WITH IT..........ROCK....... SSCOTT@MILLERWELDS.COM
Northern tool has 5 sizes of ammo boxes from "shoe box" to much bigger: $6 to $16. Save shipping if you can find one local.
Gasket in the lid may or may not be OK with gasoline. If it is, being able to open the tank to clean it every few years might be handy. If you weld a spout to the lid, take the gasket out first.
For the record, once gasoline has been inside any tank there is a major danger of fire and explosion from welding. Don't go there. Use JB Weld or such.
Hobart Expert Rock
09-25-2002, 12:09 PM
HI GUYS......ONE MORE THING TO THINK ABOUT........THE PAINT ON THE INSIDE OF THE CAN......EVENTUALLY THE GASOLINE WILL DISOLVE THE PAINT AND CONTAMINATE THE FUEL........ HOW SHALL WE GET RID OF THE PAINT ON THE INSIDE....... IF WE GO THIS ROUTE WITH THE AMMO CAN...............THOUGHT????????
I built the tank today, but I cheated a little. Digging through the shed I came across an old tool box. I cut out the bottom and 2 sides from it and then cut out the other 2 sides from the opposite corner of the box. this way all the seams were already there. All I had to do was cut out a top and then weld it all together. I used the neck from an old Coleman can and bought a venting lid from the local small engine shop. For the bottom bung I welded on a 1/8 x 1 x 1 tab and drilled/tapped it 1/8 NPT. I tested it by filling with water and put a little air to it, only 2 leaks to go over, I was happy with that.
Thanks for the responses!
Bob, you can safely weld a container that's had gasoline it in it IF it has been properly purged. I drive a gas wagon (petroleum tanker) for a living and every once in awhile I'll need some welding done to it, either internal or external. The way we purge is to either pump air or steam through it for a few hours. The guys that actual go inside and weld it use a hydrocarbon sniffer first to check that it's clean. If it's a small container I have seen them just fill it with water and then dump that out, water is heavier than gasoline and will displace it.
I used to watch a old time mechanic (from a distance) before he welded on the outside of one, he would climb up on top and open a dome lid, then throw in a match. WOOF, then he'd slam the dome closed and weld away. Once the air/fuel ratio was spent, it was (to him) safe, not for me, thanks.
My apologies. If you drive a gas wagon you certainly have a proper respect for gasoline and welding on tanks.
Sounds like the project was a success. Did you do anything to treat the inside of the tank. Seems like moisture always gets in somehow and steel that has seen welding heat might be especially vunerable to rust.
09-27-2002, 07:25 PM
There are products that will coat the inside of a fuel tank to prevent it from rusting. Restorers use it to preserve fuel tanks in old cars, tractors, etc. I mistakenly discarded a fuel tank for a generator because it kept rusting and plugging the fuel filter. A new replacement tank was over $60. Since then I have learned about treating rusty tanks. I have included a link to one company that sells such products.