Second Repair Attempt - Am I Getting It?

[JonnyAlpha]

Hi;

I have started to do some realtime repairs on my Mini.

Clarke 160EN
Adams Argon / CO2 5% mix
0.6mm Mild Steel Wire
Welder is set at Min 1 and wire speed is about 6.5
Gas set at 10 LPM but not too sure how to correctly set up my rig.

Most of the welds shown are butt welds with a couple of T joints.

Some panels bought from retailer and some home made using old metal recycled from old cabinets.

My welding is getting better but its still not good, at times I can crack it but in the main the weld sits a little too high. I'm afraid if I crank up the power I'll just blow through? Not shown in this picture a get a brown deposit on the weld which wipes off.

The tests I did on spare pieces of cabinet seemed OK.
Any tips on how to improve?

 

[octo0072000]

welds

looks like you need more amps welds look cold
have a look at the thin metal tutorials on here
http://www.mig-welding.co.uk/mig.htm
your patches need to be flush to the old metal no gaps metal could do with been a bit better cleaned up try using a flap wheel not quite as rough as a grinding disc
but it's all practice practice practice till you get better

have a good look at your earth clamp it needs to make a good contact needs to grip the metal tight a bad earth makes all sorts of bad welds
not dear try this or you could try clamping a pair of mole-grips on to the clamp to the body so it's tight

http://www.ebay.co.uk/itm/WELDING-E...043?pt=LH_DefaultDomain_3&hash=item3f0dcd9f03

 

[keith19]

Octo has about said it all.
One further point, are you holding the torch too far away, perhaps in an attempt to not blow through? Most of that welding is sitting too high, scattered about, lacking penetration. You can get this effect from holding the torch too far away from the steel.

Do a few tacks nice and close, only short ones, and check they penetrate. Move up one setting if not, and try again, till you get it right.
It's just mainly practice, and knowing your particular machine. The settings on the same make and model can vary, so personal experiment is the best way.

 

[smoggyrich]

I'm certainly no expert but it looks to me that you are not getting your tacks at a consistent size and it looks like you have a bit too much of a gap between each tack.

I have been trying to lay a tack down then overlap the next tack and allow them to melt into each other. Trying to keep them all about the same size. They end up looking like a row of fish eyes.

As Octo says it's just practice. But no matter how much practice you have it can't always prepare you for welding old thin metal some times in ridiculous positions etc.


Hope this helps.

Rich.

 

[JonnyAlpha]

Thanks for all the advice.

I am trying to hold the torch as close to the join as possible but sometimes in doing this you just cannot see what is going on and end up welding blind.

I will try to increase the Amps either by increasing the wire speed or trying it on the next setting Min / 2. Hopefully without blowing great holes in the work.

Oddly when I tested on a spare piece of repair panel the weld looked a lot better maybe at time it was the earth, I'll double check.

Most of these welds were done on metal that had been sprayed with U-POL WELD http://www.halfords.com/webapp/wcs/stores/servlet/product_storeId_10001_catalogId_10151_productId_170878_langId_-1_categoryId_165625

But this is designed to be welded through isn't it? My test piece had not been sprayed.

Will I need to go over these welds again?

Back on it this weekend (Last go for a while - off to NZ for a bit) so I'll post back the results.

Thanks

 

[keith19]

"Will I need to go over these welds again?"

I'd just grind or flap disk them down pretty close, see if there are any gaps, then fill those, doing tacks. For bodywork, deep penetration isn't critical, so long as it holds together okay.

U-POL is meant to go on the inside of panels which have to be welded from the other side. Although it is meant to be welded through, it's used as a necessary evil inside panels rather than to lay a film on top of where you're going to weld. It could have made your welds worse if it was a thick enough film.

 

[JonnyAlpha]

"see if there are any gaps, then fill those, doing tacks." - By tacks I guess you mean the thin metal technique of stop start?

 

[keith19]

Yes.
If you are in any doubt about going through thin metal because you have to do several consecutive tacks, just do one and let it cool for a few seconds before doing another partway over the top of it, so ideally they give a scallop-shell effect, a line of joined-up tacks.

 

[mantakev]

Looks to me as you don't have enough amps, slow your wire speed too.
The track looks like it's ' wiggly'
Are you holding the torch with two hands?
One to press the trigger, one to steady the torch.
Practice on a few bits until you can just make a nice slow weld and burn through, then just speed up a little .
Noise should be fzzzzzzzzp, like bacon, yum

 

[jb2000]

Go buy a 200A earth clamp off Ebay, about £3 delivered.
The Clarke clamp only bites on the smallest pin-prick edge and it is easy to get a bad ground as a result. Drag the Clarke clamp on Zintec coated steel and you will see the finest hairline scratch, that is your contact area.

Hold the torch closer to the metal.
They actually look like gasless welds with too little penetration. If you were using gasless I would say remove the shroud which can improve things greatly re ability to see AND closer to the metal. In that vein with gassed wire I suspect you are holding the torch too far from the metal - screw the shroud a bit further up, stick out is measured from the tip and not from the shroud.

When stitching the tacks together, start welding away from a tack and move onto one - the weld pool gets hot, just as it is about to blow through you have moved the heat into the thicker tack metal so no blow through, better weld, good penetration. Takes *repeated* practice to do it automatically but once you get it going *consistently* it hugely improves your welding re no pinholes, no gaps etc. Seam sealer is your friend.

 

[Zagan]

How long have you been welding for?

After all my experience I'm thinking your welder is needed the wire feed upped slightly.

Without hearing it wouldn't be too sure.

Looking at the welds it would seem to me you go a bit slow so maybe need to speed though you might be lacking in heat control, (lack of welding time) as said need to weld some more to get better.

 

[octo0072000]

you need to get the bacon sizzle going

you need to get the bacon sizzle going see you tube video

http://www.youtube.com/watch?v=f4RbBudvHLU

another one to get the sizzle

http://www.youtube.com/watch?v=AWVQmmSns_k&NR=1