Challenge EH-3D - Setting the Side Guide Stops; Fixed Gages

7.0 Accessories for Challenge Paper Drilling Machine
20
This optional backgauge assembly provides additional versatility to the EH-3D. The automatic trip on
the side guide permits step and repeat type of operation with a minimum distance between holes of
3/8” (9.5 mm) with the standard stops or 1/4” (6.3 mm) minimum by the use of a fixed gage, available
as optional equipment.
As each set of holes is drilled, the side guide is automatically tripped, and as soon as the drills clear
the stock on their up stroke, the guide is free to move to its next stop. This is accomplished by
pushing the stock to the left and moving the guide at the same time. When drilling one, two or three
holes only, that fall within the 9” (23 cm) limitations of the machine, the automatic trip bracket (located
at the left of the machine) can be turned so that it does not engage the trip lever.
7.7.1 Setting the side guide stops
First set the rear gage to the desired back margin. Be sure both sides are set to the same dimension
and tighten the two thumbscrews. Next, remove the guide shaft and set the guide stops to the
desired distance between holes (a scale in the guide shaft is provided for this purpose). The guide
shaft is then replace in the rear gage and final adjusting or centering of holes is accomplished with
the knurled screw at the extreme left end of the guide shaft.
The automatic trip gage comes equipped with seven stops. Additional stops can be purchased at a
very nominal price. Challenge fixed index gages are recommended where the same job is to be
handled over and over again. They are easily and quickly attached and removed. NOTE: When
drilling narrow strips, the side guide roller assembly should be mounted on the inside of the side
guide assembly.
7.8 Fixed Gages
For Fast, Accurate Hole Spacing
(For use with optional auto-trip backgauge only)
Figure 15
These fixed gages with pre-cut hole spacings fit on the side guide in place of the moveable stops. To
use, position the gage so that the right end lines up with the dimension on the scale for the centerline
of the first hole to be drilled. Use of the stops on fixed gages is the same as using the adjustable
stops.
In addition to 2-5 hole patterns, fixed gages are available from stock in the following standard types:
22-stop gage, 1/2” centers for multi-ring binders
25-stop gage, 3/8” centers
25-stop gage, 1/4” centers
34-stop gage, 1/2” centers
46-stop gage, 3/8” centers