[pianotech] Misc., but on topic...of sorts<G>

[Delwin D Fandrich]

>From Wikipedia:
"Durometer is one of several measures of the hardness of a material.
Hardness may be defined as a material's resistance to permanent indentation.
The durometer scale was defined by Albert F. Shore, who developed a
measurement device called a durometer in the 1920s. The term durometer is
often used to refer to the measurement, as well as the instrument itself.
Durometer is typically used as a measure of hardness in polymers,
elastomers, and rubbers.

"There are several scales of durometer, used for materials with different
properties. The two most common scales, using slightly different measurement
systems, are the ASTM D2240 type A and type D scales. The A scale is for
softer plastics, while the D scale is for harder ones. However, the ASTM
D2240-00 testing standard calls for a total of 12 scales, depending on the
intended use; types A, B, C, D, DO, E, M, O, OO, OOO, OOO-S, and R. Each
scale results in a value between 0 and 100, with higher values indicating a
harder material.

"Durometer, like many other hardness tests, measures the depth of an
indentation in the material created by a given force on a standardized
presser foot. This depth is dependent on the hardness of the material, its
viscoelastic properties, the shape of the presser foot, and the duration of
the test."

ddf

Delwin D Fandrich
Piano Design & Fabrication
6939 Foothill Court SW, Olympia, Washington 98512 USA
Phone  360.515.0119 — Cell  360.388.6525
del at fandrichpiano.com — ddfandrich at gmail.com


-----Original Message-----
From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf
Of Joseph Garrett
Sent: Friday, February 24, 2012 1:30 PM
To: pianotech
Subject: [pianotech] Misc., but on topic...of sorts<G>

Del, was pontificating about glues and asked: "...(Does this list still
accept attachments?)..."
To that I say: You betcha! (unlike that other pos list!<G> 

And then, a comment about glue(s) info he said: "But I don't think I've ever
seen a Shore hardness rating for any adhesive...."

My question is: What, specifically is "Shore hardness"?? I think I might
have an idea, but would like clarification.<G> Thanks, Joe

Joe Garrett, R.P.T.
Captain of the Tool Police
Squares R I