Woodhaven 788XL: Dado Jig - Manual (Page 6)

11. ATTACH PLATE GUIDE & ROUTER TO PLATE
Attach the Plate Guide (789B) to the Router Plate (789P)
using the 1/2" screws (MF035). See fig. 11. Follow the
directions in the 4973 Plate Hardware and attach your router
to the Router Plate (789P). An optional drill style plate (PN
789PD) is available for semi-permanent mounting of your
router, but it requires drilling mounting holes in the plate.
SELECT ROUTER BIT - IMPORTANT!!!
This jig will work with any bit up to 3/4". The bit diameter
should be no less then half the width of the dado, to allow you
to cut the dado in two passes. A 3/4" bit will cut dadoes up to 1-
1/2" wide in two passes. If your dado is wider than twice the bit
diameter, you'll have to make extra passes. A 1/2" bit (dado width
range of 1/2" to 1" in two passes) or 5/8" bit (dado width range
of 5/8" to 1-1/4" in two passes) is fine for 3/4" dadoes. A 3/8" bit
(dado width range of 3/8" to 3/4" in two passes) or a 7/16" bit
(dado width range of 7/16" to 7/8" in two passes) may suit your
needs better. Smaller diameter bits may limit the depth of the
dado you're able to cut. Once you select a bit, the jig should
never be used with another bit without installing another set
of 1/4" Fences and going through the trim operation. You
can make additional 1/4" Fences yourself, or you can order
them (789A) from Woodhaven. Install the bit in your router
and set the depth of cut to just below the 1/4" Fences.
12. TRIM 1/4" FENCES
Loosen the 1/4" Fences and re-position them so the
ends are butted up against the front of the Edge Fence on
the Front Track. Tighten the screws. See fig. 12.
Rip a piece of scrap approximately 1-1/2" wide x 24" long.
Place it between the Stationary and Adjustable Tracks, resting on
the 1/4" Fences. Loosen the knobs on the Adjustable Track and
slide it over towards the Stationary Track, with the 1-1/2" wide scrap
between them. Tighten the knobs and remove the scrap. See fig. 13.
Place the Router/Router Plate on the Tracks with the
Plate Guide between the Tracks. Loosen the Position Stops
and adjust the front Stop so the router bit will cut just a little
over halfway into the Edge Fence on the Front Track. Adjust
the back Stop so the router bit won't strike the Back Track.
Place the Dado Jig on a scrap board 3/4" thick x 10" wide
x 24" long. Adjust the Work Stops so the board is sandwiched
between them and the Front Track. See fig. 13. Clamp the Jig and
scrap to a workbench using the Clamp Pads.
Place the Router/Router Plate on the jig against the back
Position Stop, with the Plate Guide between the Stationary &
Adjustable Tracks. Turn the router on and hold the Plate Guide
against the Track on your right, as you pull the router forward.
When you contact the front Position Stop, slide the router to the
left so the plate Guide is against the opposite Track and push the router back to the back Position Stop. See fig. 16 & Cover.
USING THE JIG FOR DADOES
Perform at least one of the two steps below to prevent the jig from racking during use.
1. Position and use the 789M Outboard Clamp Pad according to section six.
2. Clamp the Back Track of the Dado Jig to the workbench, or bolt the Dado Jig to a
workbench using the T-slots in the underside of the Front and Back Tracks.
Always check that the Front Track is square to the Stationary Track before beginning. You only
need to loosen the Adjustable Track to set the Dado Jig for the dado width you want.
5
11
12
13
789P Router Plate & 789B Plate Guide
789A 1/4”
Fences
1-1/2” Wide
Scrap installed
between tracks