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Yes, brass or bronze is much heavier than the alternatives of aluminum, zinc, and pot metal. All of these are candidates for die casting or permanent mold casting because of the "as cast" surface finish possible, as well as their favorable properties for filling the mold without voids. Weight is of little consequence. If weight was a concern, these decorative parts wouldn't be used at all.
 

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Nomads 55-57,69Z28-RS,72ElCamino, Corvette(5)
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Actually my strongest complaint against 'brass' IS the weight of them (once you hold them in your hands you can definitely tell the difference). It's also the reason I like aluminum, since they are much lighter, and not subject to the voids/pitting of pot metal. Jay sold the brass pars for $4500/set when they were available, but he currently sells the aluminum ones for $3450/set... Chromed with the accent paint already done.
 

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The upside of silicon bronze is it is weldable. The eyebrow sets made about a decade ago in silicon bronze were available in 4-pc sets. The eyebrow/fender unit being a single part. Maybe some member has a set of those?
 

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The upside of silicon bronze is it is weldable. The eyebrow sets made about a decade ago in silicon bronze were available in 4-pc sets. The eyebrow/fender unit being a single part. Maybe some member has a set of those?
I've never heard of those, but I'll check into them... :)
As heavy as the liftgate is can you imagine weight of the first ~200 production units in brass?
Yes, they are significantly heavier... (A friend is investigating having some more brass liftgates made...), but I'd rather see them done in aluminum personally.

PS. The liftgate glass itself is a fairly weighty item... :)
 

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I've never heard of those, but I'll check into them... :)

Yes, they are significantly heavier... (A friend is investigating having some more brass liftgates made...), but I'd rather see them done in aluminum personally.

PS. The liftgate glass itself is a fairly weighty item... :)
#1 Those sets, in 4 or 6pc, are no longer available. It was a very low production run. And is was over 10 years ago.

#2 I was assembling, and bit later, installing mine about the time we were talking about shims at the upper hinges.
 

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My understanding of aluminum casting is that it is troublesome for dimensionally critical parts owing to the amount it shrinks in the process. This was explained to me by a person interested in reproducing ultra rare Hallock windshield frames (the stuff of early Model A hotrod legends). It is because of the shrinkage issue that I would not have expected to hear of it being used for at least the eyebrow pieces. The side pieces might more easily be cast and machined to correct dimensions, however. Anyone able to either amplify or correct this information....?
 

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Aluminum expands significantly with heat, and it's molten (HOT) when poured into a mold, so the mold has to be dimensionally larger to have the cooled/solid aluminum come out dimensionally correct (or OK?).. :)
 

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...as was told to me. Trouble is in predicting how much larger to make your mold when finished dimensions are critical...and a Nomad eyebrow would seem to be the very definition of this. Then there is further processing...machining, polishing and/or plating. Same would be at issue for a liftgate.
 

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I am wondering why it can't be done in plastic? Most if not all the chrome (when there is some) on new cars are plastic. Seems like it would be easy. Although not the ideal material, it would not rust or pit. I know most of us would not want plastic on our cars though.
Just thinking out loud.
Todd
 

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Take a heavy pot metal chromed trim part... and duplicate it in plastic, chrome it, attach it and it will LOOK the same as that heavy original part. If it were inexpensive enough to replace easily/quickly if it became damaged, then I would not have a problem with it.. :) I've had discussions with other Nomaders about this in the past... :)
 

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Aluminum expands significantly with heat, and it's molten (HOT) when poured into a mold, so the mold has to be dimensionally larger to have the cooled/solid aluminum come out dimensionally correct (or OK?).. :)
Thermal contraction issues with the relatively small cross sections of the trim is not much of a problem. Thermal contraction is especially a problem with the Nomad trim with the curvature in eyebrows and the length of the fender door trim.

The lift gate is not a simple object to cast. If you look at it, every side has curvature. The top curvature is different tthan the bottom curvature. Also the top is shorter than the bottom. Not as obvious looking that the frame but the bare window really highlights the curves.
 

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Thermal contraction issues with the relatively small cross sections of the trim is not much of a problem. Thermal contraction is especially a problem with the Nomad trim with the curvature in eyebrows and the length of the fender door trim.

The lift gate is not a simple object to cast. If you look at it, every side has curvature... the bare window really highlights the curves.
Exactly - on both aspects.

Assuming a set of eyebrows could be satisfactorily cast in aluminum, and given they could not be polished well enough (?), can aluminum be plated to look good and last?
 
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