Rockwell Conversion Chart

Cased pair of Colt Model 1849 pocket revolvers

With 150+ lots of firearms, bladed weapons and related material, 150+ lots of antique medical equipment, fine art and accessories, and 600+ lots of fine Americana including formal and painted furniture, folk art, ceramics, fine art and more, the Annual Labor Day Weekend Auction to be held September 2-3 by Garth’s Auctioneers & Appraisers, will trigger a holiday gathering of faithful collectors and dealers.   All three sessions will offer bidders a variety of interesting objects, fascinating stories, and competitive bidding.

FIREARMS: The Collection of the M.O. Hallock Family plus additions

It is appropriate that Macy O. Hallock collected Civil War firearms, as he was a relative of Civil War General Henry W. Halleck (the family name has been spelled different ways over the generations).  Of course, Hallock collected more than just guns—a 1940 newspaper article written about him describes some of his “25 collections,” including American Indian relics (his primary passion), as well as smoking pipes, fossils, buttons, coins, and much more. When the Hallock family decided to begin dispersing its multi-generational collection, Garth’s was honored to have been chosen to sell the items.

A dealer as well as a collector, Hallock and his wife, Clara, exhibited at many antique shows in the Midwest in the 1920s, 30s, and 40s, often in period costume portraying Abraham and Mary Todd Lincoln.  It wasn’t long before Macy’s son, also named Macy, joined the game, helping his father drive to and from shows, setting up their booths, and of course, selling all manner of antiques.  Today, the tradition continues as the children and grandchildren of the younger Macy travel with their father and grandfather to shows.  These days, however, the family’s focus is principally on Civil War firearms, edged weapons, and accoutrements. This session will include a wonderfully broad and deep collection from the Hallock family of muskets, rifles, revolvers, swords, bayonets and accoutrements, plus a handful of additions from other consignors.

Rockwell Hardness Test - Metal Engineering & Technical

The Rockwell Hardness test is a hardness measurement based on the net increase in depth of impression as a load is applied. Hardness numbers have no units and are commonly given in the R, L, M, E and K scales. The higher the number in each of the scales means the harder the material.

Hardness has been variously defined as resistance to local penetration, scratching, machining, wear or abrasion, and yielding. The multiplicity of definitions, and corresponding multiplicity of hardness measuring instruments, together with the lack of a fundamental definition, indicates that hardness may not be a fundamental property of a material, but rather a composite one including yield strength , work hardening , true tensile strength , modulus of elasticity , and others. In the Rockwell method of hardness testing , the depth of penetration of an indenter under certain arbitrary test conditions is determined. The indenter may either be a steel ball of some specified diameter or a spherical diamond-tipped cone of 120� angle and 0.2 mm tip radius, called Brale. The type of indenter and the test load determine the hardness scale(A, B, C, etc)[4].

A minor load of 10 kg is first applied, which causes an initial penetration and holds the indenter in place.Then, the dial is set to zero and the major load is applied. Upon removal of the major load, the depth reading is taken while the minor load is still on. The hardness number may then be read directly from the scale.

The hardness of ceramic substrates can be determined by the Rockwell hardness test, according to the specifications of ASTM E-18. This test measures the difference in depth caused by two different forces, using a dial gauge. Using standard hardness conversion tables, the Rockwell hardness value is determined for the load applied, the diameter of the indentor, and the indentation depth.

Conversion, old worlds and new

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Figures of conversion, "the Jewish Question" & English national identity

Trading classic chart patterns

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