Bongo Fury

Disappointing response from my local place in Cardiff who profess to be the #1 Bongo specialist.

I am planning to get the rear arches done, even though they look ok at the moment, I'm tired of patching them up.

Phoned the place, and he says "I'm not interested in doing the rear arches any more, because customers keep coming back with rust coming through within 6 months"

I am of the opinion that if you weld fresh metal to rust free metal, and properly grind the welds back before prepping with good primer and good layers of topcoat, that it should last as long as the original. Certainly, small repairs elsewhere on the Bongo I've done myself are still rust free after 6 years.

Seems to me that this just means they aren't doing a proper job. Can anyone think of a valid reason why rust should come back on an arch repair using new arches, other than incomplete prep etc?

Feeling a bit deflated !

Anyone suggest anyone else local to Cardiff / Pontypridd area who've done a good LASTING job ?

having watched my wifes arches (which wernt bad at all) come back to a pre done state in under 6 months i decided to do my own and save £750 plus.

both sides took me nearly 2 weeks dodging the showers as i was working outside. i suppose the point im making is that the quality of the work is all about time, and time costs a lot, if you have all the oven/lamps etc all this has to be paid for somewhere. so when you get a £1500 bill for something you cannot see it is hard to swallow.

the best rear wheel arch repair i ever saw on a bongo was on member --- flinty's - - bongo, they took off the entire off side panel and glued on a full panel, i didnt ask the price though but theres no chance of rust coming through.

heres mine.

http://igmaynard.co.uk/bongo/forum/view ... ir#p655512

Its all about the prep, primers and paints, a proper job isn't cheap as its not difficult just time consuming.
i know another garage who won't touch them as its so fiddly.
I am just going to bite the bullet and do my own then get a garage to paint it

Mine have been done by Ian Taylor over a period of time with bits being done every other year, unless you rip out massive sections and fabricate and modify to suit it's inevitable that rust will eek it's way through. On Facebook and here there are lots of posts showing some great work done by repair shops, it would be good to see how the repairs have coped a year or so on

I have to agree I've has some small sections done in the past and whilst they looked good at the time I too have been disappointed by the lack of time before it reappeared. Now its getting more serious and clearly approaching the full replacement stage, which is leaving me wondering about the best course of action.

I seem to remember from my college days that the metals where the weld takes place have an electrical reaction that will lead to eventual corrosion formation.Noble and ignoble as I recall.
Shoot me down in flames people... but it was 45 years ago
However it is of more significance that repair is sealed from Oxygen and so air as early as possible.

During the repair it is important to ensure that as much of the ground back area is sealed before welding takes place and all rusted metal is remove.
3M do a weld through Zinc oxide based paint in aerosol form that I have used on my restos in the past although this is more applicable to spot welded panels it does work well of MIG/TIG welding too.
As butt welding on a large panel can lead to distortion most tend to over lap panels.
If butt welded then the problems are largely negated as the reaction tends to occur at the point of the weld joint,and you are better able to seal the the repair so there is less propensity for moisture trapping.

Another important area for potential problems largely ignored is at the filling/ leveling stage, I dont know of many repairers who lead load and metal finish repairs any more, most tend to use a polyester body filler and this will hold water if wet flatting.
If the underlying panel is not treated before filler application then at the the wet flatting/ guide coat stage moisture can be retained in the filler and permeates through to untreated surface beneath promoting early failure - like when you see bubbling around the arc of the wheel arch repair this is normally where the filler feathers into the surrounding panel- if under lying panels are treated it may be trapped in the filler before the final primer coat is applied leading to potential surface finish defects.
Surface finish problems caused by water entrapment are more noticeable if a low bake oven is used to cure the top coat and present as micro blistering in the finish coat or under the lacquer on metallic.

Such is the economics of the modern body repair business that insufficient time is allowed for this moisture to evaporate out of the filler via normal evaporation or a short burst in the oven prior to final priming.
Smaller repairers may use air drying materials and this can hide potential problem or errors made during the preparation.

So in a nutshell proper surface treatments during, after, and prior to painting are the most important factors in the longevity of weld repairs, as well as the obvious sealing of the internals before signing it off.

In the case of Bongo wheel arches, despite some MOT stations using corrosion here as a reason for rejection they are not strictly a structural panel although they could be deemed as a supporting panel if the rusting were extensive or in a prescribed area.

In view of the above, if I were repairing my Bongo arches mainly for cosmetic reasons and they were not to far gone , I would be looking at dry repair methods.
If done correctly you would be less likely to see premature failure than a poorly welded/ prepped panel repair and you can DIY at a lot less cost too.

Great info, thanks.

That makes me feel better. I might have another go myself when the rust comes back (AGAIN). I don't want to spend £1000 on getting them done if the rust comes back through a new re-spray at another £2000 !

I know there are areas that have been filled on ours, and I'd be interested in having a go at welding in some small panels myself (when I buy a mig welder). I have some good high zinc primers I could use after welding and grinding to prevent rust before top coating. There is the option of using POR 15 as an anti-rust layer, but it works better on rough surfaces. I wonder if it could be applied to cured zinc primer if it was roughened up first. It's just I know that POR 15 is waterproof, so would be a great barrier.

Plan to use the Bilt Hamber Electrox primer. It's expensive, but supposed to be good.

Could galv metal be welded in or would it cause rusting elsewhere?

Never used those products so couldnt say.
When I use galvanised panels I just grind across the repair panel edge, if that makes sense, and keep the parent panel grinding to an absolute minimum to allow for the weld..
I lay the repair panel over the parent ,mark around the periphery and remove the repair panel. Then trim the parent back to allow a quarter inch for the weld. When the weld clean up grind is finished treat the reverse of the weld with zinc paint and then seal with Waxoyl or similar forcing it in between the parent and repair panel if you are able to access it.

Wow Northern Bongolow, you had a job on there!
They really do rot dont they.
My weekend job is to immerse Bongo in Waxoyl and leave it to soak till Monday:D

to be fair they didnt look too bad, then i did a quick bodge repair to the sharp edges as the mot date was forgotten, . so then i had an idea to sort it once and for all.

doin a front cross member for someone whos radiator fell out the other day. . gotta keep both eyes on that tin worm.

both these bongo's are very early 95 models so the rest are not far behind - - - - .

thats what i used, shoot through primer

This video is good I think...

https://www.youtube.com/watch?v=rQhG6dyX_AI

And it's a Mazda !!

Shocking what the previous repairer had done !!!

There's always these, if you can count out some of the rot

https://van-x.co.uk/mazda-bongo-ford-fr ... -of-8.html