DIY weld testing...

[JBweld]

Hi All, I've been told that a half inch long test weld should support one ton in wheight. Can anyone say this is the case?

I have a forklift......and a wheight, so if I arrange my test weld between the two (and keep well clear of course ) will this give me an indication of a sound weld?

Or, how would you do it?

Cheers, John...

 

[MigTig]

Well being me, I would say: ''yeahhh go for it '' but being a public forum we have to be sensible. You could in theory test the weld like this, but no higher than an inch or two above the ground to prevent injury, or damage to your machinery.

I would suggest sticking to good weld calculators for that. I have heard from someone of this being done using a strip of mig weld, and two tractors putting oposing forward stress on the weld, which had to be well over a ton, and no break.

But bear in mind, this was done using pre-heat, correct gas and wire, your average Clarke hobby welder will definetly not give the required strength.

You would also need to prevent the weld from getting any other stress when under wheight, such as pulling it sideways slightly, as this will add more stress and lower the breaking point.

I would love to see this tried however

 

[Drains]

I reckon a half inch long weld will do 10 tons, if the weld and the parent metal are big enough!
It's a bit of a piece of string jobby isn't it?
If you want to test your welds, do a bend test. In laymans terms that involves a vice and a hammer. The parent metal should break before the weldline fractures.
Otherwise, just have a muck about with the forklift etc. I don't know what it'll tell you.
For your boat you're better off with a dye penetrant kit, which will tell you if you're going to sink!
Si

 

[JBweld]

Thanks..........the lad that told me about this, sounded like he knew what was what.

He said to make two "teardrops", bored to take the couplings. Grind the points off, to make 1/2" flats and then test weld these flats together.

It's only for personal interest...........I've already done the clamp in vice, knock seven bells out of it, method.........seemed to work...

 

[Drains]

Do us a favour and show some pics - I'm sure plenty of us'd be interested to see it!

 

[Haze]

as I have been told a spot weld can take 1000kg...

 

[MigTig]

A 30mm spot weld @ 400+amps maybe

We had a 'Good' spot welder in the workshop, an I was never impressed with that either. Full power, and plenty of spots was the only way to go. Its more like a brased surface weld rather then ''welded''. And you cant use them on Stainless. (not the workshop sized type anyhow)

 

[Hitch]

An inch of 6mm weld should hold a ton comfortably.

Never relly on just that though!!

 

[disco_monkey79]

I reckon a half inch long weld will do 10 tons, if the weld and the parent metal are big enough!
It's a bit of a piece of string jobby isn't it?
If you want to test your welds, do a bend test. In laymans terms that involves a vice and a hammer. The parent metal should break before the weldline fractures.
Otherwise, just have a muck about with the forklift etc. I don't know what it'll tell you.
For your boat you're better off with a dye penetrant kit, which will tell you if you're going to sink!
Si

I've been doing my utmost to tear apart and otherwise destroy test pieces. I welded two bits of angle (0.8mm) together to form a box section, and then crushed this in a vice. It squished, but the welds didn't break. So this is presumably good?

I also clamped a lap weld (again with 0.8mm mild steel) in the vice along one edge, and then tried to wrench the two pieces apart. The metal tore around the weld (I was heaving on it, using a pair of moles to grip, and giving it a good wiggle in all directions), but the weld itself didn't shear. Does that sound about right?

Thanks!

 

[runnach]

To be honest .8 material I would say is not the best for carrying out destructive tests. Pretty difficult not to achieve a decent fused weld on decent quality clean material, try to lay your hands on 3mm, see how you get on with this thickness........

Cheers...........