Hand drilling

Miner single jacking  Bisbee circa 1900

 Prior to 1905 the drilling of blast holes in Bisbee was done using hand drilling techniques.  This strenuous process made the advance of the underground workings slow and labor intensive. The rates of progress varied on the hardness of the rock and hole direction, vertical being the most difficult. 

Single Jacking was the preferred method in Bisbee.  This is done

by a single person using a chisel like drill steel hitting it with a hammer  rotating the steel ¼ turn then striking it again the process is repeated until  the hole is completed.  The hammer called a single jack weighs between 3.5-4.5lbs.

Double Jacking ( Double hand)This is done by two people one person  holding the drill steel and rotating between strikes  and the other hitting the steel with and 8 to 10 pound  long handled  double jack (sledge hammer) the men would occasionally switch positions to relieve the driller.

Triple Jacking (Three Hand) this is done by two people striking and one person turning the steel.

  In all the methods  sets of drill steels of graduated lengths and widths  are  necessary. The short and wider steels are started with, the steels progress to longer and  narrower in  width  as the hole in deepened. Hand steels that have been found underground in Bisbee  range from 1 1/4” to ¾” in width. Differences in length of 21/2” to 3” between changes of steel.  How the steel is sharpened and shaped  depends on the hardness of the rock. Hand steels will have a chisel shaped tip that has the edges  is flared out. A  common misnomer about the steels is that they were shaped  like star drills used in rock quarrying.

Diagram showing different methods of sharpening hand steels

1a is for soft rock and is typical of Bisbee steels. 2b is for harder rock

The bevel is flatter in hard rock and the steel has less of a flare. In softer rock the bevel is steeper and the flare greater. Cleaning of the holes while drilling is critical, the accumulation dust will act as a cushion, softening the effect of the hammer blows.  Horizontal holes are keep clean with the use of a copper spoon (drilling spoon)to shovel the cuttings. Down holes use small amounts of water causing the cutting to cling to the steel as mud. The steel is removed every so often and rapped against a rock knocking off the mud. Upward holes cuttings have the benefit of the cutting falling out. Hand drilled holes are easily identified  by their triangular shape machine drilled hole are perfectly round.

Drilling rates using various methods and in different rock types

Augers

Typically a coal mine tool, augers were an important method of hand drilling, used to drill blast holes in the softer materials like oxides and clays in Bisbee. Several different styles have been found underground the most common are about 4 feet long and have a place where a wooden handle could be fitted.

The auger would be placed against  the soft material and rotated with the wooden handle while pressure is applied. An example of a 4 foot auger  has a place where it has be hit with a hammer to drive the auger through small area of hard ground.

Two  augers have been found that are exceptionally  long and with capabilities of drilling larger holes  The cutting diameter is the same as with hand steels in case a harder material is encountered the hole is then finished by hand drilling. In 1911 at Oliver mine the ground was so soft, breast augers  were used  to conserve compressed air. 

4’ auger found on 4th level Southwest mine

Bisbee style 4 ½ lb  single jack  and  hand steel

  Queen incline in shaft 25ft above B level  station

Machine drilling  creating  perfectly round shaped hole Queen Tunnel main drift 

References

Annie Larkin 2010, pers. comm., 8 March

Arizona Republican December 28, 1905

 A treatise on metal mining vol 3 1899, Burr printing house New York, section 38 pp. 55-56

Benton-Cohen, Katherine 2009,Borderline Americans: racial division and labor in the Arizona borderlands, Harvard university press, p96

Bisbee Daily Review July 5th 1902

Bisbee Daily Review July 5th 1903

Bisbee Daily Review June 27th 1903

Bisbee Daily Review June 29th 1913

Colliery Engineer February 1907 Vol 27 p291

Compressed Air Magazine May 1918 Vol XXIII No.5 p8766

Graeme, R ‘ Bisbee Arizona” Mineralogical Record Sept- Oct 1981 Vol 25 p 274

Horace Jared Stevens, Walter Harvey Weed, 1911, The Copper Handbook, Vol 10

Mines and Minerals, February, 1907 Vol XXVII, No.7

Mining & scientific  press, July 19, 1913 p.108

Mrs. Hugh Brown, Railroad Days: A Memoir of Tonopah, 1904, The American West, 5,   November, 1968, p.28.

Montana Butte Standard March 4,1932

Peele, R 1941, Mining Engineers’ Handbook 3rd edition John Wiley & Sons, Inc     pp. 5-07,5-08

Young, Otis, Western Mining, University of Oklahoma press, 1987 pp.185-186

The Arizona Republican, September 9, 1903

The Arizona Republican, September 4, 1903

The Arizona Republic  November 12, 1960

Richard Graeme IV 2010, pers. comm., 8 February

Richard Graeme III  2010, pers. comm., 2 February

Reno Evening Gazette January 14,1903

University Missourian October 28 1908

graemite@hotmail.com.

© 2013 by Doug Graeme