arch rust

[MK3JAY]

ive got some rust on the passenger side rear wheel arch..
what would be better to use
1.rust killer and then primer and paint or
2.hammerite anti rust primer then paint

wich will be more effective ?

 

[danh]

With rust the best thing is to cut it out and replace panels. You could try and grind the rust back and get to bare metal the rust treat, acid etch, prime then paint. But dont leave the primer exposed to the elements because primer is porus and the rot monster will work its way back in a few months

 

[Mr.Negative]

^^^Well said... its amazing how many people just leave things in primer then wonder why it goes rusty.

If you want a quick fix to it (will come through again) grind all the rust and leave nice clean metal, you will have to fill the holes with filler and give it a quick skim over as the arches look to be all the way through in places (believe me). Make sure that you seal in-between the 2 plates where the outside and inside arches meet as this is what rots them from water being trapped (use underseal, filler or you could even use a bit of tiger seal ect). Then give it a coat of primer and then lots of coats with white. I found it easy to blend my old white astra in with just spray cans so you shouldnt have too much trouble but it will come back.
By the way... if you do hammerite it you will have to be careful what paints you put over it in future (say for example - cellulose is not compatible).

I would put a repair pc on it if i'm honest but it depends on how much time and effort you want to put in it and how much the car is worth to you.

 

[MK3JAY]

thanks guys, will buy sum underseal and get it sorted its only till i get them replaced proffesionally

 

[Jaspa]

as above really, grind it back to shiney silver, rust treat to get the last little bits, acid etch, and build your layers up, did mine 8months ago and they are still spot on

 

[wayne1]

this is the best way mate

http://www.youtube.com/watch?v=WpTfFcS8oTE

 

[turbojay]

just cut it out and weld a piece in and be done with it as it will only come back, i tried everything with my rusty arch and a couple of months later it would be back bubbling the paint

 

[Turboshed]

Gonna be doing something similar to this myself in the next few weeks. Though my arch was so bad I had to have it replaced. It's currently in just a rough coat of paint at the moment. But it will be sanded back to bare metal, filled the isopon, sanded back, primed, painted and lacquered. I might even stick some rust killer on too. Just things to consider. Though I went to Oswestry body repair, they charged £120 to cut out and weld in a replacement rear arch section, for just the work only

 

[turbojay]

i did my arches, sills, filler surround myself using a bodyshop as a place to do it, the guy charged me £100 but that was using all his stuff and undersealed the whole of the car underneath etc

 

[Turboshed]

i did my arches, sills, filler surround myself using a bodyshop as a place to do it, the guy charged me £100 but that was using all his stuff and undersealed the whole of the car underneath etc

Lucky get, been trying to get down the ally at the side of my house for a few weeks, so I can dig the super sur out the shed to heat the side of the car up. Doesnt help the last few weeks when it has been nice, there have been neighbours down the ally

 

[Mr.Negative]

this is the best way mate

http://www.youtube.com/watch?v=WpTfFcS8oTE

I wont use one alone...
using wire brush attachments doesnt get into the little pin holes made by the rust and it also seems to make some rust go smooth and shiney. I've always used a combination of a wirebrush, cutting disk, grinding disk / attachment and my little dremel (not a metaphor )

 

[johnsastra16v]

guys on a mk3, does the lip of the outer arch need to be welded to the inner arch??

 

[Turboshed]

I dont think so mate, the arch lip, is just a lip, it joins the inner arch a little further back.

 

[Mr.Negative]

No... they arent as standard but I always fill / seal them as water gets in there and rots the arch from the inside out

 

[sirusmk3]

As long as the arches are sealed together, as above, so no water can get in. Id give it a spray with wax oil inside the inner arch just for a safer measure. It means taking your inside trim off but it a piece of mind if moisture gets in there. Give them a nice coat of underseal on the outside

 

[turbojay]

no they aint welded together but as said use some sealant and wax oil to fill it so no water can get in, thats what i did and no rust for 18 months so far