Wheel Arch Rust

If you need to ask, then probably not. Not being condescending, just stating a fact. Possibilities range from cleaning back to sound metal, and repairing it with fibreglass, assuming the rust hasn't gone too far into the sructure, to cutting back to good metal and welding a replacement section in, which needs tools and a workshop. That section may be double skinned, which makes it harder.

If you were to grind it back to clean metal both inner and outer even widen the centre just nicky it up and reshape it with course paper 40 grit then 120 and get a grey primer pressure pack over the top. This should last for about 2 rego checks this and the next.

You could check if repair panels are available. Some types fit over the old and are tacked in place. A bit of filler on the join and some paint should make it reasonable. Just filling is unlikely to last for long.

I think I'll give it a go, though. It seems worth spending maybe a few tens of pounds to see if I can save myself hundreds. If I mess it up then I'll have a body shop fix it. I'll probably see what can be done with fibreglass, since I don't have the means to do welding.

I assume that I'd need something to support the fibreglass, because after cleaning the rust away, I might need to extend downwards by one or two cm from the remaining metal to where the rim used to be. In the local Halfords, I see that they sell fine aluminium mesh for supporting larger patches. Would that work as a support or would something else be better?

I guess I'll need to buy tools to grind back to clean metal. But I see in the local Halfords that there's "Hammerite rust removal gel" that claims to bare the metal (after a bit of wire brushing). Or I see there's a "nylon impregnated with silicon carbide" rust-removal wheel for a power-drill. Or should I invest in an angle grinder if I want to do it properly?

=A320 of angle grinders well worth it. Heck you can get a Bosch GW660 fo= r =

=A338 at the moment.

My initial Googling attempts turned this up, which I'll have to compare with the car in daylight, but it's probably a replacement for welding rather than something that fits over the old. I'll do a more thorough web-search tomorrow.

that is the sort of part that would be very useful. cut it down till it covers all the rusty stuff, preferably weld it on, or pop rivet it on. some body filler and a quick spray over will make it all look acceptable. and it won't fall off at the first speed hump.

You could probably use one of the fancy new adhesives to stick it on.

Although old fashioned hot melt glue from the Migs probably the cheapest :-)

How's your welding?

The rust removal gel is essentially phosphoric acid: it may help bond to structurally solid metal but it's no help at all if you're painting it on rust which is just going to flake off later. You need to be fairly vigorous to make sure you really are down to bare metal.

The polywheels are pretty good: not as destructive as wire wheels. Dunno what Halfords prices are like, but I used one of these:

Angle grinder may help if you can't get the wheel in to all the angles. (100mm was the smallest I could find)

Theo

My welding is nonexistent, but just out of curosity what sort of welding is best for car applications? MIG/TIG/arc/oxyacetylene?

Theo

You don't need the gel wast of time.

Just an angle grinder with a disc so you can remove the paint back to clean metal.

Even get yourself a disc and pad for a drill should suffice.

I've seen a repair panel listed for under twenty quid, one source is:-

If you phone them or e-mail them, they should be able to tell you whether the panels need to be welded on or not. There may also be fibreglass panels available. A lot easier than faffing about with soggy glass fibre matting.

MIG is the most common. However, welding the thin stuff that cars are made of is also the most difficult thing to do with one.

IMHO, none of these rust removers actually do what they claim. There's no substitute for mechanical removal of rust. And a wire brush - even motorised - isn't hard enough to remove it all. Just the loose bits. You need a grinder of some sort. And of course that's only for the outside - the inside is often totally inaccessible.

Also, oxy-acetylene is by far the most versatile, but you pay for the versatility by needing a *lot* more skill and practice. With enough skill, sound metal and the right job, you might not even need a filler rod for a joint. And you can use mostly the same gear for heat treating stuff and cutting it. A year or two should give you enough practice.....

Not IME.

The visible rust on a car is like the tip of an iceberg; what you can see represents only 10% of the whole!

If you are thinking that the rest of the car might last four years, it may be worth getting a price to have this done at a small local repairer. Dividing the cost into another four years of ownership may make it seem more affordable.

Chris