In a message dated 98-10-11 16:25:09 EDT, d.dimitry@mci2000.com writes:
> You wrote:
>
> > Please enlighten me how a 118K psi yield strength chromoly mast will
> fail
> >before a 35K psi 6061-T6 aluminum mast? When did they change the laws of
> >physics? Wall thickness has little to do with it.
> >
> My reply: Wall thickness has as much to do with the strength of a mast as
> does the material's yield strength. Both are important factors. I will
> give you the formula for it, but first a sort of analogy. Could you drive
> your car at 35 mph through an 1/2" thick aluminum plate spanned across the
> road and firmly secured to anchored poles on both sides? Kind of chancy,
> isn't? I definately would not want to try. What if we changed the
> thickness to that of common kitchen type aluminum foil? Would you take a
> shot at it? Why not, your car would probably sail right through it with
> little or no damage.
First of all, we're talking about suitable antenna masts - not aluminum
foil. Secondly, my point was that material yield strength is more important
than wall thickness (which in amateur construction project discussions is
commonly understood to be 1/8", 1/4", etc.). My apologies - I didn't mean to
imply that wall thickness was not important.
> (BTW, alum. weighs about 38% of steel and stainless of the same Volume of
> material, for those concerned about weight.)
Weight, smeight. We're concerned about proper engineering and
reliability.
> >
> > What specifically are you talking about? Feel free to post the
alloy,
> >certification and other specifications of the aforementioned masts along
> with
> >the price. Broad allusions to the "best value in masts" doesn't give us
any
> >information.
Still waiting for this information.
Cheers, Steve K7LXC
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