Hello everyone---I recently purchased a brass locomotive from an estate sale and noticed brown spots on both the locomotive and tender.I visited Doctor Wayne today to get his opinion on this issue.I am intending to have this locomotive painted but there was some concern whether these spots may affect the paint later if they're not removed.Has anyone encounterd a similar situation and if so,I would appreciate any feedback.

Possibly something was dripped onto the clearcoat over the brass and stained it? It doesn't look like corrosion or oxidization to me.

Hello,

no effects known to me. When to model is painted the tarnish disappears completely.
What it is: <!-- m --><a class="postlink" href="https://en.wikipedia.org/wiki/Tarnish">https://en.wikipedia.org/wiki/Tarnish</a><!-- m -->
With our brass locos the tarnished spots are caused by imperfections in the coat of protective laquer. Note, even the "unpainted" loco were spayed over with a coat of clear or gold coloured laquer. This is to prevent the brass surface becoming dull within weeks.


Even in this very worst case, here foam decomposition which caused copper rust and real cavity spots into the brass surface...





... they disappear simply after painting. There is no necessity to polish the tarnished before.

Glen and Lutz---thank you for your comments and re-assurance.This is a beautiful model and I'm now confident that when it is painted by Doctor Wayne it will look great.