Working with plexiglass dies

What is the easiest way or tips and hints, to saw small cutout
designs in half inch plexiglass for hydraulic forming? I am using a
wax blade in my jeweler’s saw (just broke, need more) but it is
pretty heavy going. Are there are other blades that cut better? I
don’t have a scroll saw, but if I did, would it cut the plexi?

Thanks, Jackie Richards

well from my personal experience I use a saber saw with a fine
blade. yeah the scroll saw will work well. just make sure you go slow
and don’t push the piece too hard.

I most often use a coping saw when cutting plexiglas. Just don’t use
too much pressure on the blade or it will chip the plexi.

peace,
Richard

Skip tooth blades are good for Perspex/plexiglass, and also for wax.
They do not wander like twisted wax blades. They also do not heat up
the material so they do not stick, Scroll saw suppliers ought to
carry them.

regards Tim Blades.

Yes, a scroll saw would cut plexiglass. So would a dremel with the
right attachment.

Hi Jackie,

Surprisingly, it is easier and faster to cut two pieces of
quarter-inch material and stack them than it is to cut a half-inch
piece. Some people prefer a #8 jewelers’s saw blade, or a skip-tooth
blade. I prefer the spiral wax blades, myself.

The New Concept Saw is AMAZING for cutting silhouette dies in
plexiglas. Cuts absolutely vertically, and the finish on the saw cut
is wonderfully smooth, because the sawing is so even. The hold-down
foot helps hold the material to the tool, minimizing the physical
effort of sawing. Some scroll saws work well, but most go too fast,
and jerk the material being sawn up and down.

Cynthia Eid

I have one of those flashlight-shaped, electric cutters with a
special fluted bit, they are normally used to cut out drywall where
the electrical plugs go. The bottom piece is adjustable for the depth
of the cut. You still have to drill a hole first, to start the bit in
and the whole system works best if you have a larger sheet or strip
of plexi so you can clamp it down on a bench, leaving enough hanging
over to allow for the bit and cut-out and then cut off the part for
the die. It takes a couple of practice runs to cut smoothly but is
much faster than the wax blade. It will still need filing to smooth
the edges.

Donna in VA

Jackie,

You’ll find it much easier to saw two 1/4" thick plexi rather than
one 1/2’ thick piece. Sawblades will develop heat when sawing which
melts the plastic and binds the blade, you can minimize this
generated heat by sawing thin pieces and sawing slowly. The slow hand
wins the race in this case.

Start with two pieces of acrylic, label one top and the other
bottom. They will be stacked with your silver/gold on top of the top
die with the urethane above the stack. You’ll find it best to use a
formbox to contain your force and align the two dies.

Draw your design on the top piece of plastic, saw it out, place it
over the lower plastic and trace the upper die’s hole with a 1/8"
offset so you will end up with a lower die that has a design that is
1/8" smaller all the way around the design. This acts as a support to
the upper die. You can find instructions on silhouette dies at the
web address below:

http://poirierstudio.com/shoptalk2.htm

Click on “Silhouette Die Instructions”.

Good-luck,
Phil

Skip tooth blades are good for Perspex/plexiglass, and also for
wax. 

A terrific blade is the uniblade from Boony Doon. Hopefully that is
still sold.

Elaine

What is the easiest way or tips and hints, to saw small cutout
designs in half inch plexiglass for hydraulic forming? 

I’ve recently had the opportunity to work with a glass artist who
needed some prototypes milled that he’s using to make molds for glass
casting. The pieces range between 3-4 inches in diameter.

Perhaps it’s perhaps it’s already being done, but while milling these
large pieces, it occurred to me that a milling machine could open up
a lot of design possibilities for making molds and dies to be used in
a hydraulic press.

When I shared a studio with another metalsmith about 10 years ago, I
had access to a hydraulic press but it’s been a while since I’ve used
one, so my knowledge of the process is bit rusty. But, it would seem
to me that you could design some very interesting 3D forms using
CAD/CAM, including two-sided dies or just a one sided mold that you
could use with rubber to press-mold metal.

Plexiglas isn’t the best material to mill but Delrin or Nylon would
easily hold up under the pressure of a hydraulic press.

Has anyone made dies for press-molding jewelry forms with a CNC
machine?

Jesse
http://jdkjewelry3d.blogspot.com

Jackie, I use a spiral saw blade. Works fine. I then use files to
get the cut edge all nice and smooth. When filing,be sure to hold the
file straight up (perpendicular to the plexiglass), so that you don’t
have the inner wall at at angle.

Alma

If you buy a pack of coarse coping saw blades, you can mount them in
a jeweler’s saw frame. They ought to cut a little quicker through
that stuff than skip-a-tooth sawblades. If they have the little pegs
poked through them to fit the coping saw frame, just put the pegs
over a hole in a steel block and give them a tap with a hammer to
loosen it up. They should pull right out with some pliers after that.

Or you could just put them in a coping saw frame.

Willis Hance

Jackie, you didn’t say what kind of wax blade so I am assuming the
spiral… if so try switching to the skip tooth blades Gesswein item
186-9060 I switched to them years ago for wax and plastics because
they are more accurate than the spiral and have a smaller track and
less drift. With plex you do have to go slow to prevent heat.

Frank Goss

Plexiglass is a pain in the patootie to work with. I no longer use
if for dies.

My opposition to them:

  1. It melts as you cut it if you move too fast and gums up your saw
    blade.

  2. The “saw dust” from it is bad for your lungs. So you need a dust
    mask as you work.

  3. This same stuff infests your working area and needs to be swept
    up/ clean up, assiduously.

  4. I’ve heard the fumes aren’t good for you either.

  5. These dies can break under too much pressure.

So…having said all that what do I use?

16 gauge brass epoxied to the densest pressed particle board you can
find. (mdf?)(I have also used layers of masonite)

I cut mirror images by gluing 2 pieces of brass together. Then on a
block of particle board I mark the whole and cut it out. Finally I
glue the brass to the board and carefully (so not to nick the edges
of the brass) I finish the particle board hole with files. Be careful
to not undercut your brass by making the particle board hole too big.

Its a lot of work, but my dies last.

hth.
Carla

A terrific blade is the uniblade from Boony Doon. Hopefully that
is still sold. 

I believe these are the monotooth blades you mentioned, see the
jewelers saw blades.

jesse

Jesse,

I do all my dies on the Taig CNC now.

http://www.cartertools.com/cncjewel03.html

shows how I mill dies for the press and

http://www.cartertools.com/digikanji.html

shows how I digitize Kanji (applied to digitizing any bitmap art)
for making dies, from bitmap to earring.

Shows my latest dies.

I make them out of plain vanilla 6061, and they hold up well for the
thin sterling I use. I can go from design to earring in under an
hour, which is pretty darn fast. I love being able to do thematic
lines of earrings very quickly with this method.

I’ve made other dies from free machining steel that would probably
be better for heavier gauges, or more detail, but for what we do
aluminum is fine. I don’t do precious metal clay, but I think this
method would work for making stamps for that as well!

Nick