Mance: Quarry Industry of Southern Indiana 17 



traveling table that carries them under the saw. In most of 

 the types now in use the saw travels forward into the stone. 

 The diamond saw is more rapid in its work than the gang saw, 

 but the cost of installation and upkeep is higher. Diamond saws 

 are driven at speeds of from 500 to 700 revolutions per minute, 

 according to their diameters. The types most used in this 

 district are the Anderson, the Patch, and the Meyers saws. The 

 gang saws are usually steam driven, while the diamond saw is more 

 easily handled by electric motors. These motors are constructed 

 for either direct- or alternating-current drive, but the latter is the 

 better adapted to the work. The cost of upkeep of a diamond 

 saw is mainly due to the loss of diamonds, which tend to loosen 

 from their settings. The saw blades are usually set with from 

 80 to 150 diamonds, and the heavy work tends to loosen them. 



The following description of a diamond saw is taken from 

 the latest catalogs of a large company putting these saws on the 

 market : 



These machines are now equipped with worm drive as planers and may be 

 purchased with either single or double platens and for either belt or directly 

 connected motor drive. The platens are lined every 6 inches to guide the 

 setting of the stone. The stone need not be moved for each cut but the 

 blade is movable so that as many parallel cuts as desired can be made at 

 one setting of the stone. The platens can be driven at any speed from 2 

 to 36 inches per minute with a reverse speed of 12 feet per minute. Three 

 sets of teeth have run over 2 years and 6 months in Indiana limestone and 

 are still in good condition. 



There are in use in the district several diamond saws called 

 ^'drag saws". These are cross-cut or reciprocating diamond 

 saws. ''Drag saws" are such large consumers of power that 

 they are being rapidly replaced by circular diamond saws. 



The planer is a heavily constructed machine with a traveling 

 table on which the stone to be planed is wedged fast. The 

 uprights of the machine support heavy steel planes which smooth 

 the surface of the stone as it passes. These planers are con- 

 structed with one or two platens: In the latter case they are 

 called biplaners. The single-platen machines may cut from 

 one side or from both sides at the same time. In some of the 

 single-side planers the plane is supported by one side of the 

 frame, the other side of the frame not being present. These 

 are called "open-side planers". Planers may have their platen 

 driven by either gear screws or worm gears, the latter giving the 

 better satisfaction. All planers which cut from both sides are 



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