Inner wing treatment

[islandjj]

Hi I'm stripping the old underseal off the inside inner wings of my MGA. First, whats the best way to get rid of the underseal ?
I 'm going to spray epoxy on the outside after stripping it back to bare metal.
How should I treat the inside, I was thinking of taking the inside back to bare metal then phosphoric acid to treat any rust pits, but I'm not sure whether to hammerite the inside or epoxy bearing in mind their may be rust pitting.

 

[steveo3002]

hammerite is terrible stuff

use the epoxy once the metal is clean , its the best you can do

once you have the epoxy on you can please yourself if you fill in any pits or maybe use stonechip if its rough

 

[lotus 30]

Have a look at por 15 it likes rust but only where there is no sunlight.but believe it when they say no paint on the lid lip seal cos you will not get it back open i use cling film on the paint tin then put the lid back on also just decant enough for what you are going to paint as it will go off in the tin and keep it cool. available from FROST it's expensive but good stuff. Hammerite well not as good as it used to be it has prob had all the nasty stuff taken out.
andy b www.frost.co.uk

 

[rtbcomp]

You may be able to soften the underseal with white spirit.

 

[richiegallon]

A few years ago I had an RS 2000 and someone had undersealed the inner wings and it looked awful, I used cellulose thinners to take it off, and it left no damage to the paintwork either

 

[Daz1968]

I would use a paint scraper and get off as much as you can especially as it's still cold, then get what's left off with thinners.

 

[vdubz]

Don't waste your time with hammerite ,its rubbish, i would use jotun 87(aluminium) on the inner wings as its a much tougher epoxy and will quite happily go over bits of crap and rust.

 

[Turbo]

Stripping underseal is a horrible messy job as you are probably finding out. I found the best way is to use a blowlamp or heat gun to soften it & scrape it off with a scraper or a wire brush. You can also use a wire brush on a drill or grinder on larger areas.
I also have an electric scraper which is great for tough stuff like seam sealer. I bought mine in lidl but they're on amazon.
http://www.amazon.co.uk/Andrew-James-Electric-Scraper-Attachments/dp/B004WN52M2

Not sure about the paint but I'd avoid hammerite as the new stuff is rubbish. That Por 15 has a good reputation in the car restoration community but it's not cheap. Guess it depends on how much you value your car and how long you want the job to last. The primer coat is the most important to preserve the car, the top coats are just cosmetic.

 

[the snooper]

id use a hot air gun and paint scraper

 

[rtcosic]

I also have an electric scraper which is great for tough stuff like seam sealer. I bought mine in lidl

Concur. We've done several cars like this. Finish with gunwash thinners to remove last bits.

 

[MG David]

As I have both on the shelf in my garage I would brush Jotun epoxy on the wheel side of the inner wing and spray Lechler epoxy on the engine bay side of the inner wing. Once my Jotun epoxy is used up I probably will not buy any more and just use the Lechler.

Heat gun and scraper makes less mess and noise than the knotted wire wheel on the angle grinder but is a bit slower. When you use the angle grinder you still need a scraper to get into the corners. With both you need a solvent to clean off the residue.

I have had issues with POR15. Sometimes it works well sometimes not. I think it needs a surface with more tooth than epoxy needs. So I have given up using it. Epoxy has never given me a problem.

 

[malcolm]

Heat gun can help with removing underseal too with thinners for the remainder as above. Nasty stuff.

Well worth repainting with decent epoxy primer, stonechip paint, then body colour. I did mine a bit like that more than 20 years and maybe 30,000 miles ago and it's still good underneath.

 

[islandjj]

Thanks , I,m going for epoxy then stone chip , but how about phosphoric acid on any pits , will it affect the epoxy ?

 

[richie00boy]

It can affect the epoxy as Lechler and HB Body ones already have zinc phosphate to provide extra bite.

You are better removing the rust from the pits with citric acid soaked kitchen paper or deox gel. Brushing phosphoric on tends to just scab over the rust.