Patch or pre-formed panel?

[Dan99]

My Fiesta MKII failed it's MOT and needs 5 holes welded, so I thought I'd better learn how to MIG weld and do it myself.

First I'm having a go at the rear lower corner (see pictures). I've cut back to good metal and removed most paint and sealant. Now, I don't know whether I should buy a repair panel or patch it with a piece. If I go for the panel (see pic), it's larger than the area to be repaired, so do I weld it as it is over the whole corner area or do I cut a section out of it? Or do I cut the whole area back to the same dimensions of the new panel and weld it in as it is? Or do I use a piece of scrap metal the same thickness and cut to size. In either case do lap weld or butt weld?

Sorry for all the questions. Thanks in advance

Regards
Dan

 

[gavuk]

This will answer all or most of your questions wheel arch

 

[Dan99]

Thanks Gav, yes it's a helpful article I did read it, and I searched the forum's other postings for rear lower corner repairs before posting this - but it does not address my specific questions. But it does seem to imply that a butt joint is preferable when the repair is in an area that is exposed to road dirt.

Regards
Dan

 

[gavuk]

I would buy the patch ,easier and quicker,but thats a personal choice...if the patch is bigger ,as Malc says in that article its a good idea to trim it allowing for a full patch in the future should it become needed,butt welding is the best/correct way IF you are not trying to just get a years mot. i would probably trim the patch then mark and cut the body to suit the trimmed patch ,to ensure you are welding to sound metal ,but that depends a lot on the body ....it will pass an mot with a patch lap welded over the top,but its more time consuming and a little bit more difficult

 

[schnappi]

Depends if you're restoring it for shows etc. or just getting a daily driver through the MOT.

If it's a resto, buy the repair sections and butt weld in, grind, flap wheel for invisible repair.

If it's just a daily driver, I'd beat a patch from steel sheet into roughly the right shape and lap weld it and once through the MOT, seam seal the inside and cover with underseal on the outside. No need to turn every bit of welding into a fine work of art taking weeks to complete when the overall condition of the car might be shabby.

 

[Dan99]

As an absolute novice I'm keen to learn & follow what is 'standard' practice - whether it turns out a mess is another matter! I'd like to get the car back into looking half-decent but also thru the MOT asap....Think I'll be trying to butt weld it once I've had some practice. Thanks for the replies guys.

Regards
Dan

 

[KennyC]

I can't work put if it is curved on one plane of if it is a slight compound curve. If it's only curved in one direction I would get an engineering firm to curve a bit to near enough the shape using slip rolls (and adjust it by hand/ mallet since it will likely be 0.8mm mild steel).

 

[gavuk]

How much is the repair panel Dan ?......

 

[octo0072000]

panel prices scroll down

How much is the repair panel Dan ?......

panel prices scroll down page


http://www.auto-paints4u.co.uk/body-panels/ford/ford-fiesta/ford-fiesta-mk1-1977-1983.html?limit=all

 

[the snooper]

depends on how far you want to go the panel includes part of the wheel arch which by the looks of it yours could do with a full arch.
once the arch fails water spray fills up the sills and the rear corner hence your problem my advice would be to sort out your arches aswell to avoid more rot in the future

 

[Dan99]

Re. Patch or pre-formed panel?

Kenny, the curve isn't a simple one; beginning at the wheelarch there a 12 cm section that is, but working towards the back of the car the last 4 cms or so curves inwards from the corner too. If that makes sense. I just realised I couldn't shape one piece of sheet steel like that, so it's got to be the pre-formed panel for the job.

Regards
Dan

 

[octo0072000]

or you could make a panel up in 2 or 3 bits the panel you show only does the outer you will still have to make plates for the boot floor and inner arch ok buying the panel makes it a bit easier but you will still be making bits as well most car facter sell steel in 2x4 sheet size 1mm gives you plenty to go at and learn on as well

 

[Dan99]

Re. Patch or pre-formed panel

Thanks Octo. Jees..it's sounding tricky - but I'm up for it. Buying the panel will be a bit labour saving what with all the other bits I've got to tack on. So I'll go down that route.

Gav - I got 2 prices £32.76 (incl p&p) from Autopanels and £20.76 (+ p&p) from Hadrian but - octo - those prices are pretty good from Auto Paints £17.57 (+p&p)! Depends on the p&p though.

Snooper - admittedly the wheelarch isn't all that great towards the back of it, so I thought I could patch that area & make the new metal mate up with the new panel. Hmmm...looks like I'll be getting plenty of practice.

Regards
Dan

 

[the snooper]

when you have repaired the wheel arch get yourself a tin of seam sealer to keep out the weather

 

[Dan99]

Hello All

Sorry, this is a bit of a long post, but I thought I'd put an update here to help/warn other learners.

It's a shame I didn't take a picture of the two external pieces I used. They were 1.2 mm and difficult to bend just right. Basically one was a longer piece that spanned from the lower wheelarch to the back corner and the other patched the corner once I had made some cuts in it to enable me to bend it sufficiently in two planes. I improved the curves by tacking, clamping (mostly using a jack) and giving 'em a bash with a club hammer. I realised I would be finishing off the job with filler anyway so didn't worry about it looking a bit frankenstein-ish.

Using a small piece of transparent acetate taped over the hole helped me see where the curves start to become compound. I marked/traced the areas on the acetate for cutting and where to slit to aid the bending. The acetate was then stuck to the steel using double-sided adhesive tape and then cut and cleaned up. Later, once welded in place I filled the slits from both sides (boot side & outside) by turning up the wire speed and doing a wave-like motion with the the nozzle. I then went back over the sections with a slower wire speed to melt the lumps into a whole. Didn't work very well and I ended up with high mounds that had to be grinded off.

Also welding a mixture of thicknesses was hell. 1.2 mm patches onto the original thin floor (from too much sanding) and onto floor/panel seams of about 5 mm thick. This was something else that I was not sure about. Are the seams under the car always retained? Or is it OK to cut them out if you have access to the other side?

Do the welds (those that you can see) look OK? (Some of them look very black 'cause I put Kurust on them and the surrounding area after finishing).

The replacement wing section came from a scrap yard. It was a new replacement wing from a recent VW car but pretty well bent everywhere. I found the paint a pig to strip even using chemical paint stripper (Wickes stuff is pathetic) and a wire wheel (I mean worse than my old car). But I did manage to cut off, straighten out and use some of the curved wheel arch section. I should have finished off welding a bit of the inner arch before attaching the outer wheel arch. Sigh. You live and learn....Oh, and I thought it unecessary to seam weld small sections of the wheel arch such as here, but I did finally do that.

Unfortunately things havn't gone according to plan. I covered external welded parts vulnerable to spray and stone chips with sealant. I also covered most of the the uglier external welds with filler, sanded it down & painted it.....But now the MOT man won't pass the car 'cause he can't see the welds! LOL. Gonna have to cut a lot away and replace with a pre-formed panel and leave the welds bare for MOT man to approve. Sigh. Love MIG welding, but even so...

If I think of anything else I'll post it up here (the car's needed a heck of a lot of welding elsewhere too).

Regards
Dan

 

[keith19]

Most of it doesn't look too bad, Dan. One or two spots could maybe do with joining up a little. MOT testers do like to see the welds, but it's usually okay to give them a coat of primer before the MOT to stop rusting taking place.