Archive of the former Yahoo!Groups mailing list: Homebrew PCBs
Subject: CNC board drilling and routing
From: Alan King <alan@...>
Date: 2006-05-09
I have had it out since Christmas, but finally got around to really
getting things going again in the last two weeks. Reworked the basic
front end program to read Gerber, so now it'll route out the cutouts etc
from board outlines from Eagle. The 2.4 of the newer Gerber format is
very easy, nice having everything in the same place..
The simple, meant to be temporary mount I had worked fine for
drilling, but couldn't take a side load so was flexing around. Went
back over to Lowes the other day looking for other boxes etc to make a
better mount, and now they carry a nearly 3" deep single wide metal box,
with no punch outs on the flat sides. Not only will these work for
mounting the Dremel, but they are also large enough to handle a NEMA 23
motor. While I did plastic boxes since it was easy to locate and drill
the holes, the intent was to work out locations then make them with
metal, the plastic just worked out ok enough to not worry with it much.
But now there are very suitable metal ones available, time to change it
over. These and a simple box setup to remount the last coupler and
everything will be pretty solid. Hmm do have to redo the Z motor,
mine's a custom with lead screw, not a standard motor. Still not hard
or much to do..
Melamine base plate, wood for the cut board of course, and one wood
plank for the mounting plate for the tool holder. Even the plank could
be done away with and make the mechanics all metal, but little point
since it makes mounting the tool holder easier than straight to the
rails and doesn't affect accuracy much if at all, since it's only the
3/8" thickness that's in the X,Y dimension.
All metal mechanics machine that only takes straight cuts and drill
holes to make, and still ends up being sub-$150 with motors etc. Likely
sub-$100 if done right since the mechanics themselves end up $75 or so.
Getting it finished up over the next couple of days since I want it to
cut out my inner board cuts now.
Much of the work is in the boxes, the rest is straight cuts and drill
holes. Plus the box price drops in half if you buy a case of 20 boxes,
like $25 or $30. Likely I could CNC a few sets up and mail them out
with little if any added cost over just buying the 6 individual boxes,
even after shipping not likely $15 or $20. Wouldn't make sense shipping
the other parts though, they have flat cost and not that much work
required on them, better to just buy the rest at a local Lowes.
Could probably be brought up to doing medium machine work without too
much effort since it's metal. Most of my own uses are small or light
duty so not sure I'll take it to that point myself. Only thing big I
want for now is a 4'x8' sheet plywood cutter, and that's a different
animal..
Alan