Petrol Tanks

[stocker]

what do you guys think 1.6mm 316 s/s be thick enough top build a tank out of?its at the limit of the pan brake

[ISL33P]

I would say yes but only if you add internal baffles which would act as further support. All this will depend on the dimensions of the tank and how it will be supported in place? Will it be in the standard location or in the boot of what I am assuming is a Skyline?

[stocker]

ive made an alloy one already for the daily..............which im strapping it down and made a base/plate for it to bolt on too its in aristo actually

here the alloy one pics are of it when it was half finished.ive put 3 baffle plates ,baffle cage for the sender and fuel trap

it is an odd shape

[stocker]

started to tig up alloy.......think i need a better quailty alloy to play with as it pops alot...and some more foot control?

[scotty nm35]

I don't pretend to weld alloy anywhere near as well as Ariel, but it looks like too much heat, try turning the gas down a bit too, the higher flows can cause eddy problems.

You also need to make sure the joins are touching, the molten alloy doesn't like to fill gaps.

There are some great tutorials on the Miller website but nothing beats practice.

http://www.millerwelds.com/resources/improving-your-skills/

[ISL33P]

The gaps are your first problem, edge to edge. No gaps at all when welding aluminium. Scotty is spot on, it reflects in the weld bead and looks like sh1t and hence why you are getting the crack at the start of the weld.

What filler rod are you using?

[brenton21]

That looks like its one piece of sheet to me and you did a bead weld on it? Whats your welder and set up? ie tungsten, amps, AC balance and filler wire?

[stocker]

cracked cause i dipped in the water i should of let it cool down naturally.....that alloy gets real hot..........5% silicon filler rod...........i did find my tungsten where melting when it came to alloy?

Edited May 6, 2013 by stocker

[brenton21]

4043- 5% sil. filler prolly isn't the best choice on 5xxx series ally. 5356 - 5% mag. is to suit. What size/type tungsten are you runnin? too many amps through a small diameter tungsten will melt it.

[ISL33P]

use the 5356, the shiny but dull beads would come down to the 4043.

i'd say the crack is more due to a combination of being the start of the weld on the end of the materials & too much heat. Once a crack starts it tends to go on for a while if it isn't corrected