INCRA Twin Linear - Manual (Page 14)

14
With the infeed and outfeed fences set in-line, your INCRA
TWIN can be used for a variety of typical fence applications
including grooving and dadoing, as well as edge forming
operations such as rabbeting, chamfering, and roundovers.
You’ll also find the in-line position useful for many specialty operations. With the Hi-Rise fence cap in place, you’ll be
able to use vertical panel raising bits to make raised panels
for cabinetry, and since its design is compatible with all
INCRA joint-making accessories, you’ll be able to cut
countless varieties of box joints and dovetails.
IN-LINE FENCE APPLICATIONS
Fig. 25
General purpose fence
General Purpose Fence
The essence of any INCRA JIG is its ability to accurately
position your board for a cutting operation. In a nutshell, it is
a precision fence system. Even when used as a joint maker,
the fact is that you are simply applying a particular method of
work to a very accurate fence system to produce the many
possible joints. Above all else, the INCRA TWIN gives you
the ability to make a cut exactly where you want it.
Using the TWIN as a general purpose fence is just as easy
as using any other fence in your shop. In fact, it shares in
common four things that all fences have: the straight edge or
fence that your board will be pushed along as you make a
cut, a scale, a hairline cursor, and a clamp. You will use your
INCRA fence as you would any fence. That is, first you’ll
unclamp the carriage clamp then you’ll look through the
hairline cursor as you move the fence. When you see your
measurement come under the hairline, you’ll clamp the
fence in place.
Of course, this is where the comparison ends, because unlike
other fences, when you clamp the TWIN in place, it is exactly
where you want it to be. Just get the mark on the scale close
to the hairline cursor and the Automatic Positioning Control of
the patented INCRA sawtoothed racks moves the fence to the
exact location as you pull the carriage clamp up to lock the jig
in place. It really is that easy. You’re sure to find many cutting
situations in the shop where the precision of the TWIN will
benefit you and your work.
“Zeroing” the Fence to Your Router Bit
In order to ensure accurate cutting results from any fence for
general purpose routing, the fence must first be “zeroed” to
the cutter. To zero your INCRA TWIN, unlock the carriage
clamp and slide the fence up to the edge of the cutter. Sight
down the length of the fence to check for a gap between the
fence and the cutter. Fine-tune any remaining distance by
micro adjusting the fence position. When the gap of light
disappears, the cutter will be “zero” distance from the fence.
Check to make sure that the router bit is safely centered in
the opening in the fence. Return the carriage clamp to the
locked position, then slide the
1 / 32 " scale to read 0" under the
hairline cursor.
Fig. 26
Zeroing the fence to the cutter
For a truly precise “zeroed” setup, follow the
instructions above, then move the fence to a scale
reading of
1 / 4 " and make a test cut on a piece of
scrap stock. (Make sure the scrap stock has a
square edge and that this edge is against the
fence during the cut.) Use a pair of machinist
calipers to measure the distance between the
groove and the edge of the board. If it does not
measure exactly .250", just use the micro adjuster
to accurately fine-tune the remaining distance.
Micro adjust fence until
gap of light between
fence and cutter
disappears
After positioning the fence at zero
distance from the cutter, slide the scale
to read 0" under the hairline cursor