Hey Gang,

I am going to start on a full multi-media kit. I ahve dealt with brass and resing/plastic, but this time, I am going into the realm of white metal.

So here is my question: How/what is the best way to prep this stuff? The outer coat appears to be a powder or (in chemical terms) an oxidation layer. IS it best to remove this and if so, how?

Let me preface this with two (bad) experiences with metal. Both ahd this oxidation (for lack of a better description) and when I tried to bresh it off, I ruined the piece. When I left it one, the chemical treatment (Blacken-It) did not work and turned green.

So, before I start in on this, please advise.........!

Thanks bro's
Dave

Hi Dave,

There is only one way really for the long term. The problem is you have to get into the metal. If you just spray a primer it stays on the surface and then air gets underneath. Lead is the worst example I have come across for 'metal disease'.

The only sure fire way is to use an Self Etching Primer. It has a very mild acid base and etches the primer into the metal. I use it on steel, brass, copper and even lead.

In the UK the best is made by a firm called Precision Paints. The tins are only 50 mls, not expensive but lasts forever.

How much do you need? If you only need a small amount give me an e-mail at [email protected] with your address and I will send you some. It is sprayable but you cannot send the special thinners by post.

With regard to the existing surface oxidation, I would remove all what I could. A soft brass brush would be my first tool followed up with a rotary brass brush on a minidrill at the slowest speed. If you were to leave it on there is a risk that the etch will not go all the way through to the metal.

As a final resort I suggest you try vinegar (on an off cut). This cleans metal very, very well but you have to leave the item submerged at least overnight. If you do use vinegar (I use it frequently for cleaning silver soldered joints and recommend it) don't forget to wash off in cold water when clean.

Hope this helps.

Best wishes.

Trackpins (Peter)

Trackpins (Peter),

Thanks for the words of advice. I am going after the acetic acid route as I have both some diluted stuff (ala vineger) and some more industrial stuff. Not willing to try the Fruili tracks on the industrial, but some loose stuff will get the vineger.

As for the etching primer, being in the US (and the fact that I know DOT/ICIA regulation) that it would be too expensive to ship across "..the pond". SO, I will look for something similar at the Railroad shop in a couple of weeks when I make it to the 'big' city.

If anyone else reading this, has some more sugestions, please respond.

Later (and thanks again Peter).
Dave

Hi Dave,

Pleasure, hope it helps.

I bought my primer from a model engineers outlet.

As for resin parts, I don't think that you can do any better (unless very small parts) than acrylic car body primer. I use it all of the time and with the three normal colours, white, grey and red primer you can choose what best suits the final colour of your model. It goes on very thin, is quite hard and shrinks on drying. I won't use anything else now.

Best wishes and good luck.

Peter