[conor1n]

Hello guys,

Just a quick question. I have started work on repairing the rust on my rear arches and hit a bit of a conundrum. Wondering if you guys can help?

You will see in the drawing below, a rough outline of the rear arch and internal lip. I need to remove all the rubber sealant in the lip along with the rust. The problem is that it is all quite difficult to get at with grinder/sandpaper and possibly fill up with dirt again after repair. This has led me to consider grinding back the lip a bit, as highlighted with bright green line.

Is this advised against? I am trying to figure out any possibly downsides to this.

The plan is to bring back to metal with sandpaper + wire wheel, then use Bilt Hamber rust remover + converter after, followed by some epoxy primer/sealer to seal and fill the lip/protect edge.

There is no going back after I grind the lip down a bit.. good or bad?

 

[Triple cranks]

You can actually use the rust to your advantage. Remove any loose scale then neutralize it with any good aerosol rust treatment. It does not work on bare metal. There must be rust present. It will then serve as a primer/rust preventer. I have used both Loctite brand and Permatex brand.

 

[conor1n]

Interesting.. is that not a high risk approach.

I would rather follow my more involved approach of:

• Rust removal with grinder + wire wheel
• Chemical rust removal.
• Chemical converter for anything left over
• Seal with epoxy primer
• Paint + Clear

What do you think?

 

[Triple cranks]

My only concern is you removing too much metal. That lip is there to support the arch. If you remove too much of it it will compromise the integrity of the sheet metal.
If the damage is also cosmetic to where you can see it from outside of the vehicle then I suggest doing it the proper way. But that will involve bodywork. It’s actually very easy but if you’re not comfortable with it it can be very intimidating. It just takes a lot of time and patience if you are new at it.
The proper way would then be to cut out all of the metal that has rust and weld in a new section. Then you can hammer and dolly it into the needed shape, do your bodywork and then paint and clear.