Brass propellers... colouring & weathering?

[GlennCauley]

I have a nice set of cast brass propellers from Tehnoart, for use on U-190 (IXC/40).

My question... what should I do to colour & weather them properly?

[VonStigler]

When I began my U-552 build, I submerged the brass props in a small cup with white vinegar.  By the end of the build (about 3-4 months), the vinegar had turned green and tarnished the props nicely.  Hydrogen peroxide would probably work faster if not better

[GlennCauley]

Thank you for the great ideas!

I also considered using "blacken it" to darken the metal... as I thought the props of that day were steel rather than brass.
Then maybe vinegar or H2O2 to corrode... but I am not sure that would work.

[VonStigler]

Glenn,
I once soaked some brass parts in water mixed with Oxyclean for about 4 days and the parts were very dark afterwards. If that is the look you are after, give it a try.
Regards,
Brian

[GlennCauley]

A question about these props:

There is a radial groove just behind the trailing edge of the propeller blades.
How should I fill this in?
Ideally I want to darken the brass props by submerging them in a solution (possibly Blacken-It, Oxyclean, etc.) and not show the filled groove.

Thoughts?

[GlennCauley]

I decided on "JAX Pewter Black" to darken the metal... it works on brass AND solder, thankfully.

Dipping brass prop in the JAX darkens it in a few seconds; running under tap water neutralizes the reaction.
A few dabs with a cloth can reveal some of the metal underneath.
Afterwards am trying soaking in vinegar to see the effects.

I'll continue to play around with different things until I get a good result.

[GlennCauley]

The propellers of the time would have been steel (not brass) so there would not have been overtly brass colours exposed.
I tried different techniques to finish my propeller.   Here is what I finally settled on:

• Submerge brass propeller in JAX Pewter Black.   Metal blackens within seconds.   Remove & rinse under running tap water.   Use cotton swab to remove blackening, expose brass underneath.
• Alternate submersion between JAX and hydrogen peroxide.    H2O2 seems to add texture to blackening, and seems to almost "afix" it somewhat.
• Repeat several times to gain depth to blackened metal.
• Drybrush some Alclad II colours -- Steel, Stainless Steel -- onto prop in different areas.   Steel is dark, SS is much lighter.
• Buff & blend paint with a cotton swab.

[Capt Kremin]

Hi Glenn,


Just to muddy the waters again U190 was launched 24/09/42 from Deutsche Schiff und Mashinenbau AG Weser, Bremen. Where as U534 was launched 23/09/42 from Deutsche Werft AG, Hamburg and definitely has brass propellers. It would seem to me that each shipyard would have had a stock of brass propellers to start with and when they ran out and reordered they were supplied with steel items, so as usual with these things it is a case of go with your gut feeling. I'm lucky the hull of the U534 is still available for reference.


Regards
Jon