Bit O Welding - Best Course

[BX Bandit]

Not sure how many of you weld out there (Doc/Matt) but the best foot forward on this has me stumped some what.

Patch up?
Insert donor piece?

I'd have a stab but I'm not sure exactly what's behind the holes. I think some of it is accesible from the wheel arch, but some not due to inner structurals.



Let me know if that image doesn't work

[Kitch]

It don't work mate

[pmh]

The best advice is that whatever needs replacing is ALWAYS much more than the holes that you can see!

Nowadays repairs to structural areas require seam welding all round - no more spot welding a patch over a hole. Also you need to to see if there are hidden structures inside a box section for example.

Difficult to comment on your specific problem since the picture you posted has not worked. Maybe you can describe the area and how big the holes are?

My experience with MIG welding is that it is possible but will take a lot of practice to get good strength and a good looking finish. Visit a few of the welding websites for good advice - some of the cheaper kit have significant design issues.

[docchevron]

Email me the picture bandito, I could do with a laugh!
No seriously, I could!
And maybe offer some advice too.. after I've stopped laughing!

[citronut]

what is required for MOT purposes is any area which falls into the 30cm circumference, were it was originally spot welded you can spot/tack weld, and were it was a solid section you must weld all the way around

regards malcolm

[Dollywobbler]

From what I've learnt, which is not very much, welding is actually a very small part of the job. Most of it is preparation and then protection afterwards. A lot of prep is needed to ensure the area you're welding is fully clean (both sides!) or it won't go well. A friend has promised to teach me how to weld this year. Would save me a lot of dosh...

[BX Bandit]

/\ I agree prep and aftercare etc.
I'm ok on the structural stuff, so long as it's done properly I don't concern myself with aesthetics.
This is front section of rear wheel arch/rear door shut and it's on the valver so I want to do it right before brandishing the grinder.

Doc you old goat, you're laugh at my woes are ya? You big meany, boo hoo.

I'll work on the picture, including email to Doc.
We soon changing internet provider so hopefully no more poxy proxy

[mat_fenwick]

I'm burning up with curiosity to see where you mean, Bandit! But not sure why you're asking as you've welded before haven't you?

As he said /\ it's the cutting out and making repair panels that takes more time, and it makes the actual welding so much easier if you can cut back to untouched shiny metal when dealing with car panels rather than grind back corrosion.

EDIT - crossed posts there. I've just done something similar on mine although not severe - the other side has more rust in the seam which will be my next task. I had to cut into the top edge of the sill to use the grinder to cut out all the rust; I tried using an air saw to start with but then my only blade broke.

[BX Bandit]

I have welded before mate yes, but not on visual body work (except sills).
I'm normally rushing as it's the two week grace period after MOT failure.
But I have time on my side and it's the valver so I want to get it right. Plus, there a number of ways of mending this which is the main purpose of the thread.
Right, lets try again on the piccy.

[BX Bandit]

OFFS

[BX Bandit]

this

[BX Bandit]

[mat_fenwick]

Can see the first one now - quite a bit worse than mine! In fact I'm embarrassed about my small hole.

I think the only long term way is to drill out the spot welds and tease the seam apart, so you can get right into it. Is that a hole by the sill or just black paint? The middle hole looks like you'll have access to both sides at least, which will help.

I found on mine that when I cut out the seam sealer between the inner wheel arch and the outer skin (on the inside roughly where your scratch is) I got water pouring out. So obviously water had been getting into that seam from inside (don't yet know how) and rusting its way out. Perhaps the same on yours?

[BX Bandit]

In fact I'm embarrassed about my small hole.

Don't be embarrased chap!

The black is a hole mate. I think it continues into the sill, so I shall have to take the sill kit off which I'm not looking forward to.

I was wondering whether to cut the whole section out and let a new section in. That may be overkill, and a patch by patch job will suffice?

I really don't know. And lets say I do drill the spots out and tease the joint apart, how do you treat the inner parts? If welding is needed then I shall 'have' to remove the outer section.

[mat_fenwick]

I'd probably patch, but don't know if that would be the 'best' way. For any rust in the seam I used Bilt Hamber Deox gel, which removes rust rather than converting it to black stuff that hides the unconverted rust underneath it…if you get back to shiny metal then you can't go wrong. Seems to take ages though but not tried it in the summer when it should apparently be faster.

I first used it when replacing the screen in the Disco:
http://www.bxclub.co.uk/forum/viewtopic ... &start=887" onclick="window.open(this.href);return false;

But you're right - if you find the metal in the seam has rotted away the whole wing will need to come off IMO for a lasting repair.