32 replies to this topic

[Hendred]

Hi all,

 

What do you accomplished welders on here do with a blow hole (not that you would have any if you were accomplished) but say you did?

 

I tried a bit more weld to cover hole and it worked on some but not on all holes.

 

Any tips and I would be grateful, just want to avoid filler!!

 

John

[ChopperHarris]

Using what welding?

If MIG, turn power down, perhaps wire speed up a little. Weld alternate sides of hole.

If tricky, you can place a copper plate (flattened copper pipe) on the reverse side

[Carlos W]

Try pulse welding, literally, just touch the trigger until you see the arc, then off again. You can build up the holes like that

[Icey]

It depends why it's blowing through.

 

If it's blowing because you're putting to much power in - turn down the power. If you're trying to stick/arc weld, forget it. Although I'm sure there are people that can manage it, you'll get better results using MIG or TIG on panels.

 

If it's blowing because the metal has thinned due to corrosion - you need to cut more out. It's common when repairing panels which form a void (doorsteps, a-pillars etc..) for them to look bright, shiny and healthy on the outside but be eaten away on the inside.

[Hendred]

Thanks Harris, Carlos and Icey, I'll try all 3 of your comments, I am using Mig by the way, already on lowest setting it can go so must be the metal as you say Icey.  I will try the tips to fill the holes, thanks again

[Carlos W]

What kind of welder is it? IS it gas or gasless?

 

You could try turning up the wire speed a bit.

[ChopperHarris]

what thickness wire....6 helps if metals thin

[Icey]

Thanks Harris, Carlos and Icey, I'll try all 3 of your comments, I am using Mig by the way, already on lowest setting it can go so must be the metal as you say Icey.  I will try the tips to fill the holes, thanks again

 

What gauge wire are you using?

 

And also, what panel are you repairing? Part of the learning is recognising when patching isn't worth the hassle and that whole panel replacement would be quicker and result in a better finished product.

[Hendred]

Clarke 150TE Gas on wire speed 6, level 1 MIN 0.6mm wire

[Hendred]

 

Thanks Harris, Carlos and Icey, I'll try all 3 of your comments, I am using Mig by the way, already on lowest setting it can go so must be the metal as you say Icey.  I will try the tips to fill the holes, thanks again

 

What gauge wire are you using?

 

And also, what panel are you repairing? Part of the learning is recognising when patching isn't worth the hassle and that whole panel replacement would be quicker and result in a better finished product.

 

Brand new innersill to old floor, the old floor must be the problem.

[sonikk4]

Are you butt welding or lap welding. If you are butt welding the you may have too large a gap. If you are over lapping then it sounds like the wire speed may need to be increased slightly.

If the old metal is clean and not thinned down from paint removal ( what did you use to clean up the area???) then it welding technique at fault and not the metal.

[spiguy]

One thing I would say is that if you have a good run of strong weld, then a small hole, don't go trying to fill it 'properly'  - ie it is tempting to try to fill the hole to the same standard as the rest, which usually doesn't work and ends up making it worse.  If the rest of the welding is sufficient and strong, then content yourself with just filling the hole so it isn't a hole anymore. I find that very short pulses - like Carlos said, just sparking it - should build it up quite successfully. You can add little tiny bits of weld at different points around the hole until you have filled it.

[sonikk4]

If the hole gets bigger then stop. Get a flattened piece of Copper tube behind it then slowly fill the hole with weld.

[Hendred]

Are you butt welding or lap welding. If you are butt welding the you may have too large a gap. If you are over lapping then it sounds like the wire speed may need to be increased slightly.

If the old metal is clean and not thinned down from paint removal ( what did you use to clean up the area???) then it welding technique at fault and not the metal.

I used a cutting disc on a grinder (flat onto metal) to clean the paint off could this have thinned the metal???, I am butt welding with no gap surprisingly, got the cutting spot on.

[Carlos W]

 

Are you butt welding or lap welding. If you are butt welding the you may have too large a gap. If you are over lapping then it sounds like the wire speed may need to be increased slightly.

If the old metal is clean and not thinned down from paint removal ( what did you use to clean up the area???) then it welding technique at fault and not the metal.

I used a cutting disc on a grinder (flat onto metal) to clean the paint off could this have thinned the metal???, I am butt welding with no gap surprisingly, got the cutting spot on.

 

 

Yup, probably a bit harsh