Can someone tell me why my welding is so rubbish?

[Muddy42]

16 hours ago, doobin said:

It’s simple. It’s because you’re using flux core. 
 

flux core is nothing more than an auto feed arc welder. You will have all the same problems repeatedly striking and arc, of putting enough power into it to penetrate rusty metal without blowing through. So you set it lower to not blow through and you’re surprised when your welds are crap. 
 

Get yourself down your local motor factors and get a bottle of sgs or hobbyweld rent free 5% mig gas. 
 

basically until you strike the arc and start burning, the flux isn’t burning off the give your weld protection.  There’s always a delay when staining the arc and the protection is nothing like the surround of gas from a mig shroud either. Because you have to keep stopping and starting your welds are crap. Using a proper mig, the gas is always protecting your welds, so you can start, stop just before blow through, wait a split second for the red hot glow to dissapate and then go again, all whilst protecting the weld with gas. 

 

Interesting that does make sense. I can get decent flux core results when welding thick metal, more power and longer periods of welding.  Its any thin metal or repeatedly tack welding where the results are poor. 

 

I do have some proper MIG wire and a few disposable gas cans.  

 

Thanks.

 

[doobin]

13 minutes ago, Muddy42 said:

 

Interesting that does make sense. I can get decent flux core results when welding thick metal, more power and longer periods of welding.  Its any thin metal or repeatedly tack welding where the results are poor. 

 

I do have some proper MIG wire and a few disposable gas cans.  

 

Thanks.

 

Be careful as the disposable cans are usually just co2 which is not the best shielding gas. It’ll give you a similar messy result a lot of the time. 
 

if you want a decent job especially on shitty thin metal then you need a 5% argon mix. 

[Muddy42]

34 minutes ago, doobin said:

Be careful as the disposable cans are usually just co2 which is not the best shielding gas. It’ll give you a similar messy result a lot of the time. 
 

if you want a decent job especially on shitty thin metal then you need a 5% argon mix. 

 

Actually Ive just checked and my disposable cans are 86% argon, 14% CO2. What about that?

 

I'll do some testing first. Last time I tried them my local Hobbyweld only had massive canisters and were trying to puish me towards rental which annoyed me. I'll try them again.

Edited Friday at 10:11 by Muddy42

[Muddy42]

@doobin

[GarethM]

9 minutes ago, Muddy42 said:

 

Yes CO2. OK, I'll do some testing first. Last time I tried them my local Hobbyweld only had massive canisters. I'll try them again.

They might be big cylinders, but it's not rental.

 

Think the tank I've got in the shed is about 5 years old and still 3/4 full, costly but not bad for the occasional user Vs those little machinemart rip offs.

[Dan Maynard]

Edit - that's what Doobin said first time.

Edited Friday at 11:37 by Dan Maynard

[doobin]

3 hours ago, Muddy42 said:

 

Actually Ive just checked and my disposable cans are 86% argon, 14% CO2. What about that?

 

I'll do some testing first. Last time I tried them my local Hobbyweld only had massive canisters and were trying to puish me towards rental which annoyed me. I'll try them again.

14% argon is what’s called a ‘heavy’ welding gas mix. It’s for

welding thicker steels, it lets you get the heat into it more easily with greater penetration. If you’re used to 5% gas it’s remarkable the difference it makes- your dial positions pretty much end up swapping over, with more wire feed than voltage for once. 
 

I keep a bottle at the yard mainly for site work, welding RSJs and the like. It’s not really what you want for a thin mower deck, and it also gives a much messier weld with more splatter than 5%. 
 

go on, treat yourself to a bottle of the good stuff. It’s just a deposit and then the price per fill. Get your deposit back when you decide you don’t need the bottle anymore. 

Edited Friday at 13:20 by doobin