Introduction
Scribing Lines
Using a Center Punch
Using a Compass
One good way to lay a part out on a piece of stock is simply to plot out a 1:1 scale drawing of the part and glue it to the part surface. If you do it this way, you can be sure no errors will be made in transferring the part from the computer to the suface of the part.
If a scale drawing is not available, the part can be layed out by hand.
First, apply a thin coat of blue die. If you apply too much, it will
have a tendency to flake off when you try to scribe a line through it.
You can use a square and a scribe to make a line perpendicular to an
edge on your part. The scribed line will be about 0.002 inches wide, so
you can make a reasonably accurate part by milling up to such a line by
eye.
(click here for video)1.6MB
Another way to scribe lines offset from an existing feature is with a
caliper. First, set the desired offset and lock it in. Then, run the
caliper along the edge of the part scribing a line with the point of the
caliper as you go. This is quick and easy, but somewhat less accurate
than using parallel plates.
(click here for video)1.5MB
The centerpunch creates a dimple that tends to guide the drill bit to the proper location. Withou the dimple, the drill bit can "walk" away from the desired location.
On to the bandsaw.
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