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Old May 24, 2012, 11:44 AM
Silent Flight
Twyl's Avatar
United States, CA, Cypress
Joined Jul 2005
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Brass vs Copper stock/round for ballast

I've got a quick question regarding solid brass or solid copper rounds used in ballast tubes (i.e. NOT lead filled brass/copper tubes). I'm trying to judge the pro's and con's of the two and figure out if there is a reason some people use one rather then the other.

The basis of this question is that I feel that I've seen or read about more people using brass then copper, but going with the assumption that heavier is better (that's the purpose of ballast right?) then why wouldn't copper always be the first choice? Is it due to the price of brass being less then copper? Does brass ding, scratch, corrode less, or have some other desirable property? Is my observation flawed and are both used just as equally or perhaps copper IS actually used more?

-Jonathan
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Last edited by Twyl; May 24, 2012 at 12:38 PM.
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Old May 24, 2012, 12:23 PM
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A quick check revealed that copper is nearly 50% more expensive than brass. (3/4" X 12" at Mcmaster Carr)
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Old May 24, 2012, 12:52 PM
Silent Flight
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United States, CA, Cypress
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Quote:
Originally Posted by bluzharp View Post
A quick check revealed that copper is nearly 50% more expensive than brass. (3/4" X 12" at Mcmaster Carr)
Thanks bluz, that makes sense then. Using this weight calc, the slight weight difference between brass and copper would not merit paying double.

I think we can consider this case closed

-Jonathan
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Old May 24, 2012, 02:05 PM
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Now tungsten is another matter. Expensive, but twice (2.3 X) as heavy as brass.
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Old May 24, 2012, 07:21 PM
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Eldorado CA
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A better bang for your buck right under the weight to size ratio of tungsten would be Molybdnium. You can buy round stock of all sizes from mcmaster Carr I believe. I stumbled upon this heavy metal last year when we did a small job at our shop and been hooked to it ever since, super heavy and reasonably priced.
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Old May 25, 2012, 03:40 PM
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A quick reference: Density in kg/cu.m

brass 8430-8730
Molybdenum 10188
lead 11340
copper 8930
steel 7850
tungsten 19600
titanium 4500
aluminum 2600-2800
magnesium 1738
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Old May 25, 2012, 10:27 PM
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Old May 25, 2012, 10:29 PM
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I found this site with densities listed. http://www.simetric.co.uk/si_metals.htm
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Last edited by Jim.Thompson; May 25, 2012 at 10:31 PM. Reason: link added.
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