Chassis painting preparation

[Chris71]

I've decided to paint the chassis rails in the engine bay while the engine is out, but reached a bit of a quandry.

There were a few areas where the paint/coating was starting to flake, so I've scraped those off. As a result I'm down to the bare metal in small patches while there's what looks like two layers of paint in others. Do I now:

a) Use emery paper to blend between the two surfaces and then apply a coat of primer to the whole lot, followed by a top coat.

b) Apply primer only to the bare patches, wait 'till it dries, then emery it down and apply a top coat.

c) Try and strip the whole damn lot down to bare metal. Really trying to avoid this as most of the existing paint is sound, plus the body is still on and the car is on the ground, so access is very tricky - I can remove flaking paint from anywhere (and I think with suitable masking I'll be able to get a brush in too) but actually stripping decent paint down would require more tool access

[nuttyfruitbat]

hi if youre thinking of future body off,just patch up option a or b,then do it properly with body off.if youre not thinking of body off in future then has to be option c,as you will always wish you had done it properly.highly recomend wire cup wheels for removing paint/rust,use por 15 its the best ive come across for paint.

[haircutmike]

I did this very thing the last few evenings.

Probably a body off when time allows so for now a scrape back, prepare and paint the best I can given access and time constraints!