DEEP scrathes in metal - old school repairs?

[Arrowhead]

On the '55 Thunderbird I did and the '69 cutlass I'm working on now, I've found very deep scratches like someone used a very aggrssive file on the metal. They are not in a swirl pattern, more like a sweep pattern. Was this required "back in the day" to get filler to stick? I know metal files were and are used, but this looks more like a cheese grater.

 

[Barry]

No was not needed for filler to stick we used these files back then to knock out high spots in metal, all part of metal finishing when the metal was thick enough to do that. .

 

[chevman]

This is something I have run into several times also, and what I have seen is too deep for a file to make. I think it is a 36 or 24 grit disc on a grinder and they just swiped the metal with it. I have looked at evercoats recommendation on what metal scratch they want for appling filler, and its all the same ----80 grit. But I have heard a lot of old timers say that you need a deep scratch for filler.

 

[strum456]

I found some deep scratches in the metal on my 34 chevy. Based on the direction they were running, my conclusion was that they are from the die that stamped the parts (but I really dont know).