Fig. 281. Another Method for Locating
Second Hole



"Vi



f



Fig. 282. Cast-Iron Jig with Solid Cast Legs



Jigs with Legs. When jigs are made for permanent equipment,
or if they are to be used constantly, it is well to provide some means
of elevating them from the drill-press table to avoid inaccurate work



189



180



TOOL-MAKING



occasioned by chips. If the jig is of cast iron, the legs are sometimes
cast solid with the jig, as shown in Fig. 282. In order that th^ jig
handle may be grasped in a manner that will not tire the wrist or





Fig. 283. Jig with Cover



hand, and in order to give sufficient room between the handle and the
table of the drill press so that the fingers may not be cut by chips, the
legs should be made of a length that will raise the handle about 1)



o





j l^Wbrh





Fig. 284. Covered Jig Showing Space between Work and Leaf

inches above the table. As cast-iron legs of this length would be too
weak, it is customary to make the legs of tool steel, hardening the

ends that come in contact with



e



e



^5--



the drill-press table.
Jig for Rapid Work. While
the form of jig shown in Fig. 256
would give satisfaction on cer-
tain classes of work, the process
of putting the work into the jig
and taking it out would be very
slow, as it would be necessary to
clamp the work securely to resist
the pressure of the cutting tools.
