PDA

View Full Version : Copper Bar and Windows ??????



JoeLee
07-26-2011, 11:26 PM
Well now that I've got your attention............ thats what I was saying. A friend of mine brought me a bunch of 3/8" x 3/4" copper bars today, some were about 3 to 5 feet in length. I don't think he really knew what they were and I didn't either at first until I looked a little closer. He said they were around some plate glass windows on a building that was being torn down. The bars have a grey finish on them that resembles powder coat but I don't think that is what it is. I started to peel some of it off and it comes off the bar as if it were a vynal coating of some sort. The bars are definatly copper, I would say pure copper as they are real soft and you almost can't handle them with out bending them in that length. What would they use pure copper for in window trim?????? You don't see pure copper in anything, it's just too soft. I've worked with several copper alloys like mallory 100 (buss bar) beryllium copper, tungston copper etc. but not the pure stuff. Any clues???

JL.....................

38_Cal
07-26-2011, 11:37 PM
Don't really know, but did the building's previous owners have a really cool selection of tin foil hats to go with the copper window trim? :D

David

Scottike
07-26-2011, 11:44 PM
Did the building have stained glass windows at one time? Perhaps the architect or owner didn't care for the look of lead framing aroud his windows.

tdmidget
07-27-2011, 12:28 AM
Don't really know, but did the building's previous owners have a really cool selection of tin foil hats to go with the copper window trim? :D

David
Every body knows that is your first line of defense due to the high conductivity.:D

Evan
07-27-2011, 02:08 AM
Pure copper is very commonly used for roofing and outside trim on buildings that are built to last. If you see a building with what appears to be a green metal roof it is likely copper roofing. It forms a coating of green corrosion (usually sulphates from pollution) that then protects the underlying copper which will last for centuries.

Here is an example of a pure copper roof on the Hotel Vancouver.

http://ixian.ca/pics9/hotelvan.jpg

Krunch
07-27-2011, 06:46 AM
Here is an example of a pure copper roof on the Hotel Vancouver.


I bet that gets hit by lightning a lot!

DFMiller
07-27-2011, 09:19 AM
Krunch
We get lighting around here as often as you get an honest politician around your part of the world. :D
Dave

HWooldridge
07-27-2011, 09:45 AM
Depending on weight, that could be a bunch of $ in scrap value at today's prices. Each of those bars should weigh 12-15 lbs or thereabouts - copper is bringing around $4.30 a lb; each bar could be worth $50-$60.

lakeside53
07-27-2011, 11:22 AM
Yes, worth selling unless you have a need for it. Last week I got $3.75 lb for bright copper, and $2.75 for #2 copper (assorted copper with surface oxidation and some paint, old pipe etc). It might be worth a few passes with a a fine wire wheel to "brighten" it.

macona
07-27-2011, 11:49 AM
I would hold on to it. If anything with the mess things are in right now raw materials are going to go up more.

Your Old Dog
07-27-2011, 12:46 PM
It's probably used simply because some archetect called for it. My friend in the high end lumber business says it is unreal what these archetects call for and the waste they generate simply by not being in the know.

If there was a structual reason I could see where really huge windows would be more earth-quake proof if hung with soft metal frames.

Black_Moons
07-27-2011, 01:42 PM
It's probably used simply because some archetect called for it. My friend in the high end lumber business says it is unreal what these archetects call for and the waste they generate simply by not being in the know.

If there was a structual reason I could see where really huge windows would be more earth-quake proof if hung with soft metal frames.

Ugh! I really wish designers would learn more about manufacturing/construction, It would majorly reduce costs and waste and labour.

Simple example, your milling a part and design calls for a square inside corner.

Well, good bloody luck with that on the mill. Time to grab some files, or a shaper, or use a TINY TINY endmill that can hardly remove material and still can't make a square inside corner. Oh, And you made the part WEAKER.

Now, that exact same part, with a 1/8" radius corner, and other designs changed to match (if they even needed to be, It could be the mating square part allready HAD rounded corners), Might not even need a toolchange to make that inside corner.

The guy making the part who knows better, likey won't change that square inside corner to a round one, After all, Hes just making a part to spec. Hes not paying for it, hes not designing it, Hes not authorized to change it, And hes not gonna get paid for asking the designer if he wants to change it to save money.

Anyone who knew anything about making parts would know that milling square inside corner = pain in the ass, Square outside corner = no problem (other then burrs)

Yet a designer with no manufacturing experiance might think "Square. thats easy. Rounded inside corner? that likey takes another step and might be difficult to program a curve in, Definately takes me an extra step to set the radius when designing the part"

Black_Moons
07-27-2011, 01:47 PM
It forms a coating of green corrosion (usually sulphates from pollution) that then protects the underlying copper which will last for centuries.


Why does copper roof last for centuries, But copper pipe only lasts 50~ years?

kendall
07-27-2011, 01:53 PM
What was the building originally designed for?

We built a small place for 'secretive' company that had blowout panel/windows held in with soft copper bars that operated like spring clips. ('secretive' because there was no name on the prints)

The frames had matching V grooves, place bottom bar, set window in, tilt it vertical, slip side bars in, then press top bar in place. Window frame had slots cut in so it would flex.
Periodically someone would come around and test the installed windows with scales (push or pull the windows out) and have you either install longer rods or trim a bit off the installed ones. The ones that passed you just pushed back in place.

memorable because other blowout panels I've built have used lead 'washers' as the securing method, and when they blew you had to completely reinstall them.

Evan
07-27-2011, 02:02 PM
Why does copper roof last for centuries, But copper pipe only lasts 50~ years?

It isn't sitting filled with an electrolyte 24/7.

Black_Moons
07-27-2011, 02:58 PM
Evan: Good enough reason for me.. I was suspecting that the water flow might typicaly be high enough to erode the protective oxide coating.