Mr whippy welds, driving me mad (picture enclosed)

[darrenh]

hello everyone, apologies for asking for help on my very first post!

i've been welding sporadically over the last year or so, mostly hobby and basic automotive stuff. i'm improving with practice and advice from skilled welders but one thing is persistently driving me potty...

when i halt welding i have a lovely pool glowing in the visor, it looks good (relatively) parent metal is glowing and shows penetration. as the weld cools these little mounds build themselves up from the perfect smooth pool, literally appearing from the surface like expanding foam or mr whippy icecream.

probably school boy errors on my part, but i want to learn

many thanks

 

[darrenh]

p.s its a clarke 151TE using argon/c02, .8 wire, power max 2, wire speed 7

 

[bigbadbugga]

Is there a coating on the metal you are welding, there looks to be a lot of soot like deposits around your welds.

Is the gas flowing well? I'd be checking for a blockage in the shroud.

 

[Sean]

contamination on the back of the metal? rusty deposits do this as they gas and boil to the surface, if you grind back there is a hole in the middle. I get this as my car is welded together along flanges in all the panels, some as many as 4 layers you always get a nipple on the puddle welds from the corrosion that exists between all the layers.

prep the back of the metal too, nice and shiny.

and Nylocs dont like heat

 

[Engineer]

Try more power and lower wire speed.............these need to be set up pretty accurately on DIY type welders. You need to get hold of some clean 2mm off cuts of sheet steel, and practice with the different settings until you start getting better results.

 

[octo0072000]

need to clean

i agree as above you need to clean that dexion up so it's shiny metal bit more power maybe as well

 

[malcolm]

Have you tried cutting through the welds to see if they are full of bubbles? Any Mr Whippy bits at the end of a weld would be generally down to pulling the torch away too quickly and loosing gas coverage, but they aren't normally that bad so something is going on.

 

[darrenh]

Is there a coating on the metal you are welding, there looks to be a lot of soot like deposits around your welds.

Is the gas flowing well? I'd be checking for a blockage in the shroud.

yeah there is a thin layer of paint, shroud is ok and gas flowing well.

contamination on the back of the metal? rusty deposits do this as they gas and boil to the surface, if you grind back there is a hole in the middle. I get this as my car is welded together along flanges in all the panels, some as many as 4 layers you always get a nipple on the puddle welds from the corrosion that exists between all the layers.

prep the back of the metal too, nice and shiny.

and Nylocs dont like heat

its all definately rust free, is it possible the wire itself is contaminated as the welder is stored in a garage? p.s the nuts are just to clamp the joins during welding

Try more power and lower wire speed.............these need to be set up pretty accurately on DIY type welders. You need to get hold of some clean 2mm off cuts of sheet steel, and practice with the different settings until you start getting better results.

more power seems to stop the points forming but eats through this metal too agressively, and also less power stops it but obviously less penetration. real pain as it does it when i think the settings are spot on.

i agree as above you need to clean that dexion up so it's shiny metal bit more power maybe as well

fair do's. so the moral of that story seems to be contamination, and prep further around the work area

Have you tried cutting through the welds to see if they are full of bubbles? Any Mr Whippy bits at the end of a weld would be generally down to pulling the torch away too quickly and loosing gas coverage, but they aren't normally that bad so something is going on.

i tried cutting through a whippy section and its hollow, inside is like sandy texture.

p.s i really appreciate all of your replies, thankyou