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Shining brass - the crown on your job!!

Many UK built, or at least UK originated, steam locomotive has brass installations. Bell, safety valves, sometimes lamps, cocks and last but not least the dome. These parts are usually supplied as lost wax cast brass.  The surface of these parts is anything but shiny, whereas the prototype usually was kept in tiptop condition by its crew.

At model railroad shows I have seen many a model with these brass parts straight from the box, a yellowish tarnish but no shine, no glory

I built a 7000-serie loco of the Dutch Railways, issued by DJH Engineering. This model includes the afore mentioned parts in brass. I wanted them to be bright and shining. I figured out a simple process to achieve that and in this special I want to take you by the hand and share my "secrets" with you. You'll end up with a set of beautifully shining loco parts!!

Getting the brass bright and shining is actually an easy job.
Please do not cut the parts loose from their respective castings before you finish the polishing job.
The parts are usually very small to handle and I can tell you from first hand experience that parts can get very much lost when they snap out your tweezers during polishing.

The procedure is simple. With needle files I remove any trace of casting burrs. Be careful to respect the curvature of bell and dome. If you file a little too fast, too furious you'll have a flat on it and you'll have a hard time to disguise it by filing even further. Simple but accurate work.
Next the parts are sanded with 230, 600 and 1200 paper respectively. A tedious job but yet again, simple.
Than the Proxxon (Dremel) comes to life. Fitted with a polishing disc and some polishing paste and tuned to some 5.000 rpm, it takes only a few minutes. When I did this for the first time I wasn't very comfortable about the result, but when I cleaned the dome I was relieved to see bright shining brass. Clean it with a silver polishing cloth and tadaa!!!

A sneak preview of a previously finished dome and bell. The right bell will be subject of the following photo demonstration

 


The start: a small bell, left over from my 7000 kit. A casting burr can clearly be seen on the front side

 

 

<< All necessities in view

  • A Proxxon, preferably on a drill stand,
    you'll have two hands to work with
  • A polishing disc
  • Polishing paste
     
 
Filing the burrs and other imperfections. Be careful!!  

Sanding with 230 paper.

Not just the burrs but the entire bell must be sanded. When you leave the bell to the casting you can handle much easier than I demonstrate here. Handling it with pincers is possible but it always brings in the risk of snapping away. I've spent quite some time on my knees staring for a fugitive bell.

     
 


After polishing the bell carefully on all sides, clean it with a silver polishing cloth.

 

 

 

<< The real thing!!

     
 
The breathtaking result, if I may say so myself, of ten minutes work.  

Now compare this little gem with the ugly duckling at the start.

If you take a close look you can see the camera mirrored in the bell!!