Bridge Pins, was Bridge Capping Materials: Ebony?

[Steve Fujan]

---------------------- multipart/alternative attachment
Hardened stainless steel gets my vote.  Not only is it harder (hence more
wear resistant), it is also considerably stiffer than titanium.  The more
flexible titanium would bend more right where the pin enters the wood
causing higher stress right where you don't want it.  The stainless steel
would spread the force over greater depth into the bridge.

Plus hardened stainless in these small diameters should be relatively easy
to make, hence cheaper, er..  less expensive than titanium.

Steve Fujan (BSME, MSME, PE)
www.fujanproducts.com


On 12/2/05, Dean May <deanmay@pianorebuilders.com> wrote:
>
> >>In other words, the smaller the hardness number the harder the steel.
>
> Ooops. That's backwards. A softer material will have a bigger diameter
> dent and a smaller hardness number. A harder material will have a
> smaller dent and a bigger hardness number.
>
> I am suspect of the numbers you are quoting, Ron. The little research
> I'm doing shows Vickers hardness of mild steel at 140, Hardened steel at
> 900, and titanium at 970.
>
> Then on an ask the experts site someone asked the hardness ranking of
> various metals. Here is the answer:
>
> In General- and I have to qualify that by saying I'm considering the
> metals to be in the annealed condition, the aluminum is 1100 alloy, the
> T6 (not annealed, but age hardened) aluminum is a 2000 or 7000 series
> alloy, and the titanium is 6Al-4V alloy rather than the commercially
> pure stuff (6-4 is a lot more common than CP)- the order would be
> aluminum, brass, bronze, T6 aluminum, mild steel, stainless steel, and
> titanium. If the metals are in their hardest conditions, from heat
> treating or cold work, the order would be aluminum, brass, T6 aluminum,
> bronze, titanium, mild steel, and stainless steel (cutlery grades).
> (http://experts.about.com/q/2280/1021526.htm)
>
>
>
>
>
>
> Dean
> Dean May             cell 812.239.3359
> PianoRebuilders.com   812.235.5272
> Terre Haute IN  47802
>
>
> -----Original Message-----
> From: Dean May [mailto:deanmay@pianorebuilders.com]
> Sent: Friday, December 02, 2005 8:29 PM
> To: 'Pianotech'
> Subject: RE: Bridge Pins, was Bridge Capping Materials: Ebony?
>
> Hardness in steel is tested by machines that try to put a dent in it.
> The bigger the dent, the softer the steel. The hardness number given is
> inversely proportional to the diameter of the dent left in the steel.
>
> Check out http://www.gordonengland.co.uk/hardness/vickers.htm
>
> Dean
> Dean May             cell 812.239.3359
> PianoRebuilders.com   812.235.5272
> Terre Haute IN  47802
>
>
> -----Original Message-----
> From: pianotech-bounces@ptg.org [mailto:pianotech-bounces@ptg.org] On
> Behalf Of Ron Nossaman
> Sent: Friday, December 02, 2005 5:41 PM
> To: Pianotech
> Subject: Re: Bridge Pins, was Bridge Capping Materials: Ebony?
>
>
> > Titanium probably does resist grooving better that what is
> > usually used for bridge pins.
>
> I find a Vickers hardness of 60 for titanium, and 98 for mild steel.
> Why would titanium "probably" resist grooving better when it's a
> softer material?
>
>
> > I've thought about stainless, is it
> > harder than what we usually use?  Any other improvements to consider?
>
> Go here.
> http://www.matweb.com/search/search.asp
> Prospect to your heart's content.
>
> Ron N
> _______________________________________________
> pianotech list info: https://www.moypiano.com/resources/#archives
>
>
>
> _______________________________________________
> pianotech list info: https://www.moypiano.com/resources/#archives
>

---------------------- multipart/alternative attachment
An HTML attachment was scrubbed...
URL: https://www.moypiano.com/ptg/pianotech.php/attachments/00/5c/b2/3a/attachment.htm

---------------------- multipart/alternative attachment--