Does anybody know...

[Bren]

..what I can use on sills that replicates the hammered/crackle finish that is applied under the paint?

[beko1987]

A hammer before you paint it?

[castros_bro]

http://www.hammerite.co.uk/products/direct_to_rust_metal_paint_hammered_finish.jsp

[rainagain]

A can of spray on stone chip?

 

e.g.

 

http://www.halfords.com/motoring/paints-body-repair/rust-removal-treatment/hammerite-stonechip-shield-black-600ml

[oldcars]

Mate at the bodyshop told be that's its from a shultz gun. He used one on the Shuma when the rear quarters were cut out and welded up.

[Mr_Bo11ox]

you need an overpaintable stonechip like 'Gravitex' or summert

[BavarianRetro]

Gravitex

[cobblers]

Aye, Gravitex. Cracking stuff. Kits off ebay including a gun aren't too expensive but you'll need a compressor.

One bottle will do two full sills.

 

Experiment on some scrap first to get your technique right and thin it a bit if the weathers cold otherwise it'll be too textured to look stock. Feather the blend down the sill (or do the whole thing) and gently nib the surface and your top masking line off with some 400 grit once it's dry to get the most factory finish.