Re: Pen Plotting

Here are instructions for an inexpensive one. Too simple for a
drawing, requires only a drillpress or lathe and hacksaw:

Parts List (under $10.00 at the local hardware store here, many will
have the parts in a junk box in the garage):

1) 2 pcs hex caps for 1/2 pipe
2) 1 pc 4" long, 1/2 pipe nipple
3) 1 pc 3/8 dia x 2 1/4 long spring, roughly .030 wire, .25 pitch
4) 1 pc lawn mower wheel bolt
5) 1 Sanford Sharpie felt tip marker

-Drill one hex cap to 7/16 hole. This is clearance for the skinny
part of the sharpie, but will not allow it to pass through.
-Deburr the ID of the pipe nipple as they some times will not be
opened enough for the thickest part of the sharpie. A sharpie will
fit inside a 1/2 pipe nipple.
-Drill and tap a 3/8-16 in the center of the other hex pipe cap.
-Saw/part off the wheel bolt so that the thread and a short section
of the 1/2 diameter is left.

Screw the shortened wheel bolt into one cap and onto the pipe nipple.
Drop the spring down the nipple, followed by a Sharpie without the
cap.
Screw the other hex cap over the sharpie.

This gives a good .1-.2 inch of spring loaded travel for the marker
and gives good results on large uneven surfaces, like plywood laid on
a router table.

Use hatching in your CAD program to make very nice filled sign
letters. I think that .08 was a good hatch spacing for solid fill.

Vector Connect-at-Z will make a continuous toolpath from the hatching.

Best Regards,

Fred Smith
IMService