Fence Dogs - a
Precision Dog for a Fence
How would
you like to have a fence for your workbench that can be removable but
also know it will be square when re-installed? Those days are near. The
only reason to bring a square is if you want to see how square your
square is. These pictures are of the prototype during testing. We are
still working out the details. We hope to be in production soon.
You can see it has been designed and is in the engineering stage now
and I’m planning on it working with holes slightly smaller than
3/4 inch (about 18.8 mm) to 20.3 mm. That’s right, something that
can work on traditional workbenches also, but only to the accuracy of
the hole positions.
Testing the prototype on a Festool MFT bench has been remarkable. I can
repeatedly install, remove, and re-install the dogs with an accuracy of
.002 (2/1000) of an inch. Here is the Fence I’m using, a piece of
8020 Inc., model 25-5013 extrusion and 2 ea. 25-4115 inside corner
brackets.
For installation I use a 1/4 bolt, nut and fender washer. You can
tighten until you no longer have any play with the hole and can still
move the dog up and down, or you can continue to tighten until it
is very snug in the hole and can’t move. Remove the installation bolt,
nut , and washer; and now you are ready for use.
I recommend only tightening until you no longer have any play in the
hole. This way you can slide the dogs out and move them to other sets
of holes. I know many of you will never move your fence in which case,
you can really snug them tight and not worry about them dropping out of
the holes.
I also recommend buying them for use on one table only. This way
you won’t have to take the 2 metal pieces apart. I’m aware many of you
won’t have this luxury so I will explain the easiest way I found to
disconnect the two metal parts.
Use your installation bolt, nut, possibly an extra nut, and the fender
washer. Assemble them finger tight and stick it over a table hole with
the long bolt sticking up. Slide the Fence Dog over the bolt with
the slotted female taper part pointing down. Place a screwdriver
against the female part and lightly tap the screwdriver with a hammer
until they slide apart.