Welding Question??? Newbie

admin

What size in inches is 12 gauge?? Also I am welding a fuel tank. Is it better to weld from the inside or the outside??
Reply:12 gauge is .1096" in hot rolled steel. So a bit thicker than 3/32" and less than 1/8". Be aware that not all materials are the same inch thickness at the same gauge. Alum or galv sheet will be a different thickness by a small bit.As far as inside vs outside to me that would depend on how you are building it and what process. If FC wire I would keep the weld on the outside to keep the tank interior as clean as posible. Gas mig, in or out, it would depend on how easy it is to reach the joints. Some welds like baffels almost have to be done on the interior unless you plug weld or slot the tank and weld the slots up.I assume its a new tank you are building and its made of steel.
Reply:DSW thanks for the fast response. I will be using a Flux Wire Welder that is 90 AMPS. So what is the best, inside or out??? The current tank I have looks like it is welded on the outside. But I need it strong.Thanks
Reply:Take a good look at the specs on your machine. 90 amps seems light for what I would say is 1/8" for all purposes. Run the machine at or slightly over the recomended heat for 1/8". If 1/8" is at max then I would run some solid tests and think hard about how well you can weld.I would weld the exterior of the tank from the outside. On an outside corner you will get better penetration than on an inside corner usually. Baffles I would weld both sides if posible. ( I asssume its a transfer tank or an aux tank) Clean those welds as best as you can to keep te slag out of the tank.Don't forget to check the tank for leaks. I would put air presure to it say 5-10 lbs and see if it holds or soap the seams and welds and see if you get bubles. Its a lot easier to fix it now rather than later. Be very careful at starts and stops. I would back weld or overweld those area to avoid leaks there. If posible see if you can'nt get the tank bent to eliminate weld joints. Why run more beads than you have to.Post up some more info on what you are planning and some may have some other suggestions. Good luck.
Reply:DSW has a lot of good points. Try to minimize the welds you need to do. clean everything you can before you weld, and clean as much slag and glaze if it is fluxcore as you possibly can. Pressurize slowly up to2-5 PSI. You will see a box tank bulge a bit, or hear it bump with only a few lb of pressure- tube and sq. bumper stly tanks will take a LOT more pressure before bulging. Anyway, 2 psi will show any leaks with soapsuds on ALL welds. Grind any leaks down, and then re-weld. Don't just spot weld onto the top of the holes. Re-test until it is A-O.K.And then, after so much work...... you have it in your hand, and you look over to your side...... and the runner has run off. Leaving you holding the prize, wondering when the runner will return.
Reply:Actually, 12 gauge is around 11/16 in inches, or .69 cal......
Reply:Made me look twice at that one till I got it. ( Wish I had thought of that earlier! )
Reply:Originally Posted by DSW Made me look twice at that one till I got it. ( Wish I had thought of that earlier! )
Reply:TEK, that last one just about made me spit all over the monitor.Thanks for the laugh!