Bob, Brass actually comes in several colors. The differences are in the amounts of what metals are used in the alloy. Brass is an alloy of copper and zinc, in different proportions to produce different characteristics. There are also varieties of brass that have other metals added as well, adding to the variations. Some of these are called "bronze", mostly from a historical perspective, although bronzes are usually copper and tin, not copper and zinc. Both can have many other metals added in the mix. You also have another color of brass on your layout, that which is commonly known as "nickel silver". Even that one can have a variety of mixes, but it is indeed technically a "brass".
Metallurgists have had lots of fun over several centuries experimenting with the different mixes of metal alloys and discovering their different characteristics. Hardness is one important consideration, as is malleability. Thermal expansion is a variable, as is conductivity, as well as resistance to oxidation. And if you take a piece of nice "gold" colored brass and put it in a propane flame for a few minutes, it may change color to something more "red" or "brown", and may be easier to work with. Brass "work hardens" meaning that as you bend or hammer it, it gets harder. If you reheat it, it loses it's temper, or "softens" so you can work it some more. There are, to be sure, large reference books dealing on the differences of the many alloys. But when I'm working on my new engine, all I'm asking for is "brass." Be"S"t to ya Darrell --- In [email protected], Bob Werre <bob@...> wrote: > > I have a question that has been bugging me for some time. It doesn't > seem to make any difference when working with brass...but there seems to > be two colors of the stuff. One color is a dull brownish bronze flavor > while the other is the more common brighter 'golden' color. Why the > difference? > > I've started to get my painting area cleaned up to work on several types > of brass trucks, plastic trucks, boxcar doors, and two brass Geep 30's. > One of the 30's has a chassis that is this dull brown color while the > rest of the engine is the lighter color. > > Bob Werre > BobWphoto.com > ------------------------------------ Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/S-Scale/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/S-Scale/join (Yahoo! ID required) <*> To change settings via email: [email protected] [email protected] <*> To unsubscribe from this group, send an email to: [email protected] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
