I have used two brands of rust converter, those to the left in the pic. Not both at the same time. Corrostabil is quite strong but I have to run out of the garage every time I use it. After washing, drying and rust converting I painted everything with zinc primer exempt for welding surfaces. All welding surfaces are painted with zinc spray. I have also tried cleaning everything with vinegar and water ( learnt from Pete at diy automotive school on youtube) also tried citric acid and water. Don't know what more I can do. I don't think that the POR 15 used a lot in US is sold in Sweden. Do you have any hints of better products available in Sweden?
The reason for asking is that I used the Biltema one once for "converting" some surface rust but I cannot say that I was happy with the result as the surface rust came back a couple of months later.
Perhaps my prep-job wasn't good enough, don't know...
I've heard that the Eastwood Rust Encapsulator is the best but haven't tried it myself. Dunno how many places that stock Eastwood products around here though, but there was at least one company south of Sundsvall that used to sell them.
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