Small rust spots......how do i fix them?

chris1200

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Hi folks
My 95 c220 has a few little rust marks. None bigger than a 10p coin I suppose. I'd like to sort them before the winter makes them even worse. I'm not experienced with this kind of task but I do have patience on my side!!!

My immediate idea is to chip off the surface rust, use something like a dremmel thingy to remove any rust underneath, put on some primer, then put on the paint with a small brush........

.....but I'm hopeful someone here will be able to tell me how it REALLY SHOULD be done!!!

Any thanks you can give me would be greatly appreciated.

Regards
Chris
 

Xtractorfan

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Would suggest that scrape away the flaky rust n paint, then use the dremel to gently grind away the rust...finish off with the wire brush..either drill or dremel powered to get rid of all the little rust spores that are in the pit marks...you could use a magnifying glass to check that all the rust is gone... when the rusty areas are clean. wipe the area with cellulose thinners and dry off....
Now if you so wish you can use a rust inhibitor, but I personally dont have much faith in them... Some people on here have mentioned a product called POR15 and it seems to have a good reputation for keeping rust at bay...
Next i suggest you treat the bare metal area with an acid etch primer...ACID 8.. is a good one, from your local motor factor..you can sparay or brush.. now let it dry ..heat helps. hair dryer , heat gun etc.. now use a filler or stopper to fill out the pitt marks, sand this down with a block and some 400 sandpaper.. ...for rust spots you wont have acres of filler to rub so 400 will work fine.. ..
Now when you are happy with the finish..dry off and rub your fingers across the area and feel if it is flat and level.. if not fill again and block it in again..
Noiw primer..if any bare metal use a coat of acid 8 dry off and paint over with an aerosol primer filler... when dry flat off with 800 or 1000 grade sandpaper and paint on your colour.. then lacquer..
 
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Xtractorfan

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Oh if you do end up with any holes, you need to fill or weld these up...ordinary filler or fibreglass wont last.. if you cant weld them the next best product out there is fibreglass resin... buy one of the small fibreglass kits..mix up the resin as per instructions do not add the fibreglass..and paint the resin into the hole...it will be hard to get the resin to stay as it is liquid and very runny ..so only mix very samll amount at a time..it also hardens very quickly so samll amounts at a time and dont let it drip onto mouldings sills or tyres it sticks like the proverbial...

Oh and one other thing... if you intend to use your car whilst doing the repairs...only do a small section at a time.. most people go mad with grinders and sanders over the whole car and end up with a nightmare..
 
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chris1200

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Hello Xtractorfan
Thank you for a great in-depth explanation of how to do this job properly.
The spots are not that big as I said, but I see the value in your advice about doing it right. From what I can see most of it is just surface, or just below surface, so thankfully the welding shouldn't be needed. Your advice about getting the spores out of the pit marks is something I would never have thought of. Again.....thank you for your help.

Chris
 

Xtractorfan

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If you leave the spores they will eventually find a way thru the metal or the paintwork...one of the reasons for cleaning well with cellulose thinners is that the thinner is extremely volatile and aggressive and will neutralise any small spores that remain....also warmth and dryness is essential as rust is fed by dampness and air ..deprive it of these two essential feeders and it will abate..
 

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