To spray or not to spray.

[chickenjohn]

Yes, I've used that one too (upol acid - it can also be used for the ali panels on the traveller. Thanks Alex, i'll just give it a try on a small area. I have had problems in the past with a 2nd hand panel, but who knows what paint was used on that over the years.

I do know I need to get rid of the top coats on Dibble as its 2-pack, but that comes off easy with a hot air gun and scraper.

[chickenjohn]

Dunketh, taxi black is very close the the BMC BLK-1 if you spray the whole car it will be fine and on my car past blended repairs do show up but only under certain light conditions.

[jonathon]

John, I advise caution regarding going back to the 'red' original primer. It can and often does cause a reaction as you describe. Acid 8 also is not without problems, and is best used very dry, do not wet up as you would standard primers. I'm sure you don't , but try to avoid putting filler over any original paint always go to bare metal and key this well with a 36 grit linishing pad on a grinder.

[Orkney]

Used to use an industrial etching primer on new galvanising it was called meredent solution - blue colour (bit like copper sulphate solution) - it was nothing more than Phosphoric Acid.
On new hot dippped galv it turned it instantly black.

Very important thing when using and imagine applies to other etching primers is wash it thoroughly once the application has dried - dont do so and any acid residue is sure to cause problems with your grey primer or undercoat - which may not be obvious until you apply the top coat.

[Orkney]

sorry - Moredent solution - bad spelling day

[jonathon]

I would not advise washing down etch primer as you should only use it sparingly and its porous. Once etch has dried normally 15 mins in heated booth, but upto a few hours in an unheated garage, you should follow straight on with your primer.
I think you need to be liscenced for using phosphoric acid now as its pretty evil stuff, and turns all steels either blue or black. Its an excellent preserver, and is used by Cummins as an etch mixed with a coloured etch to paint their engines.