Filling small gaps

[HuwD]

Hi all,

This is one of my first projects. Please see attached picture.

I had to do some filling to make the join. However the metal hasn't gone deep enough. When I try to grind away the excess it leaves little holes. When I try to fill them the new metal just sits on top of the hole so when I clean it up I'm left with the same holes again. It's a little too fiddly to work from the inside.

Is there a way to fill the holes or should I cut out the join and start again? Any other ideas?

Thanks

 

[Peloquin]

You should be able to fill the holes with weld. Try filling them with spots of weld. Make sure the metal forms a small pool and it should fill a hole. Try doing them one at a time.

 

[cumbriasteve]

You should be able to fill those with a good hot run, are you at the top range of your MIG?

 

[pedrobedro]

Start from a bit further back than the edge of the hole where there is still a bit of metal to weld to. Turn the power down a bit at a time till it stops blowing through, steepen the gun angle and weld to the edge of your weld you have just deposited. Work round the hole a bit at a time and join the welds together. It's bodging but if it's just for a cover up it's alright. You would be better employed making a piece to weld in there as it looks like a lace curtain at present.

 

[HuwD]

I had turned the power down as it was just blowing straight through. However maybe I should turn the power up again and if it blows through just refill it?

 

[zx9]

I had turned the power down as it was just blowing straight through. However maybe I should turn the power up again and if it blows through just refill it?

Is there room to clamp a copper block or squashed copper water pipe behind the metal, this will alow you to run a hotter weld without blowing more holes. Don't worry the steel weld will not stick to the copper.

 

[HuwD]

Is there room to clamp a copper block or squashed copper water pipe behind the metal, this will alow you to run a hotter weld without blowing more holes. Don't worry the steel weld will not stick to the copper.

I wandered if I could do something like that but wasn't sure if the copper would melt. I've got some old copper pipe I could hammer into shape. Might give it a go.

 

[Chris Stevens]

If you have holes in thin material, unless you make sure the damaged area is well below the good material when you weld up the holes, its almost certain the holes will come through again as soon as you have the surface level again.

 

[cumbriasteve]

After another look I realise that metal is thinner than I initially thought:

I think you have had too little power for fear of blowing through so it's sat on top and not penetrated to fill the voids.

You need to up the power a bit and use the thin metal technique, a good hot tack - stop - repeat - stop - repeat etc etc

You end up building up on the previous tack and hopefully have had enough heat to get down into the exisiting metal as well as bridge across the holes.

As mentioned, a heat sink behind the weld will make it easier to achieve.

 

[trewjohn2001]

Like Chris mentioned - you will end up going around in circles if the tacks aren't below the contour of the finished shape.

The surrounding material has probably thinned from grinding and shaping. You will have the heat down to compensate for this and the tack will just sit on the edges of each side. You could try flatening with a body hammer - build up and shape with weld.

I had a similar problem with a rear valence - complicated shape and very thin steel.

A backing strip would give you something to bite into.