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  View original topic: Ouch! That was bad
Chickensoup Mon Apr 05, 2021 4:54 pm

Well... This is humiliating.






My last welds were 20x better than these!

Was it the rusted metal?

the amps seemed ok.

or was it the dull/ bent tungstun?

66brm Tue Apr 06, 2021 6:51 am

Rust will do that to a weld all day long, 90% of a good weld is material surface prep

infiniteLoop Tue Apr 06, 2021 9:26 am

Do you wire/mig weld?

Chickensoup Tue Apr 06, 2021 9:27 am

Tig. The metal was pitted and rusty however I wire brushed. Even then I couldnt get the rust to completely go away

bomberbob Tue Apr 06, 2021 10:08 am

Probably should have tickled it with a grinder.

infiniteLoop Tue Apr 06, 2021 11:18 am

If you can't remove all of the rust I would push the nozzle with flux-core or MIG. It's hard enough to keep the electrode from getting contaminated with perfectly clean metal.

scrivyscriv Tue Apr 06, 2021 6:50 pm

I see lots of buildup and some porosity, with average penetration. Not horrible. Looks like you couldn't see well under the hood judging by the wandering path-?
The porosity is from a lack of gas... either you moved the torch away from that area too soon or your gas flow needs to be higher.

And yes you're fighting yourself if you weld over unprepped metal. A mig might have been a better choice for the dirty base metal you have

modok Tue Apr 06, 2021 8:51 pm

That is a rust sandwich. You did not clean in between the two layers.
TIG especially needs to be clean to get good results.

it's fine tho. you don't really even need to weld it. The wheel cylinder pushes left and right equally so there is almost no force on it.

raydog Wed Apr 07, 2021 7:15 am

modok wrote: That is a rust sandwich. You did not clean in between the two layers.
TIG especially needs to be clean to get good results.

it's fine tho. you don't really even need to weld it. The wheel cylinder pushes left and right equally so there is almost no force on it.

Exactly, That area is only supposed to be tacked in a couple of spots from the factory. No need to perma-weld.

Chickensoup Wed Apr 07, 2021 9:41 am

Ok so it seems like rust was the culprit. How should I of removed it? I used a wire brush and nothing happened.

I put that bead on there because the two layers had split and the cylinder was dangling. Let me see if I can find a pic.

Thanks

Eh, you cant really see it but here it is,

infiniteLoop Wed Apr 07, 2021 10:16 am

With flux-core on thicker metal you really only have to clean up a spot where you arc from first. I guy I work with doesn't even clean up metal he mig welds so I did some experiments with it. :shock: A lot of wire does end up on the floor though. :lol:

For rust like that I use a knotted brush on a 4.5" grinder. Then maybe clean it up with vinegar or acid. Vinegar is about as good as muriatic acid. Phosphoric acid is nicer to use and worth the extra money in my opinion.

Sand Blasting would give the best single process method to clean it up.

orwell84 Fri Apr 09, 2021 6:35 pm

I love crappy Harbor Freight blast cabinet. Makes the most unpromising part look worth salvaging again. I started welding up some punky backing plates and people were like...just get new ones, which I did but guess what? The old ones actually fit and welding them in just not all that hard compared to finding different spacers or having shims made or whatever.

And oh yeah. The old ones actually fit. And the aftermarket parts do not. They are all off in some small way no matter what it is. So if it is going to require arts and crafts and endless diddling, I would rather spend the time on something that will FIT and not give my money to the People’s Machine Works in Wong Dong Province.




And the same with rusty heater tubes...the steel just comes out of the tetanus bucket of scrap and sparky spark, it turns back into a serviceable German part.







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