Sandblasting resists

To those of us in Orchidland who are using sandblasted textures:

I have a question for those who regularly use sandblasting /
beadblasting as a texture. What do you use as a resist or mask? On
flat surfaces? Curved surfaces? Fine or delicate details?

I have been using electrical tape on flat surfaces, since it is easy
to apply and can be cut with a scalpel blade to create patterns.
Also very easy to remove. I use nail polish (the heavy duty type
favored by high school girls) as a mask for areas with fine detail
or where it would be hard to mask with tape. It’s a little harder to
remove, and will abrade at the edges if you get too aggressive with
the silicon carbide.

I’m sure there are plenty of alternatives to these. What’s your
favorite?

Douglas Zaruba

Hiya! You could use a material like JETTSETT to create a mask - work
it soft to exact detail and let it harden. Attach a handle or make it
easy for you to grasp. Then use it as a mask over each piece to
block out the sand. It is permanent and you do not need to bother
with solvents or polishing clean-ups.

I hope that helps - or at least presents a fun challenge!!!

Rachel Silber
www.SILBERS.inc

    To those of us in Orchidland who are using sandblasted
textures: What do you use as a resist or mask? On flat surfaces?
Curved surfaces? Fine or delicate details? 

Hi Doug,

  1. I’ve used masking tape to cover big areas.

  2. I’ve also used an electric waxer to apply wax as a resist on
    small areas.

  3. I used a vacuum form to make plastic masks for production items.
    The soft plastic works on items that have undercuts. We’ve used it
    in conjunction with cutting away areas with a scalpel to sandblast
    the centers of flowers/petals while keeping shiny, polished borders.
    Care has to be taken not to have too much undercut because this
    plastic is so soft, it stretches really thin if you’re not careful.
    It’s also a good idea to let the plastic cool completely, even
    dunking it in water, before taking the workpieces out. The plastic
    gives a little so you can get a snug fit. Recently, I had to put
    spots on a stingray charm. I basically shrinkwrapped the item with
    this soft vacuformed plastic and then cut tiny holes with a krause
    bur and electric waxer. The holes were cut a little smaller because
    the material gives a little when sandblasting so the resulting spots
    are a little larger.

  4. I have used the stiffer “coping” plastic (half millimeter
    thick/.020 inches) with a vacuform for production sandblasting of
    fairly flat components that are sandblasted on only one surface. The
    plastic masks off the bottoms and sides. Sometimes, I slightly prop
    up these flat pieces on scrap pieces of sheet metal to give them a
    slight undercut around the edges (the plastic shrinks around and
    slightly under the pieces). This allows me to pop the pieces snugly
    into the mask without them flying out during the sandblasting. When
    I’m done blasting, I flip the mask over and flex the plastic with my
    thumbs to pop the workpieces out.

  5. I’ve also put pieces into the fingers of surgical gloves,
    stretched the latex tight and then carefully burned away rubber with
    an electric waxer. Then, I’ve gone back and sealed the edges and gaps
    with hot wax applied with the electric waxer.

Hope this helps you out.
Donna Shimazu

Doug,

while I’m not sure I’ve a favorite, one we often use is just
injection wax, applied with a wax pen. You have to warm the metal
just a little bit, so the wax will stick to it, and then build up
enough of a thick layer so it doesn’t abrade. But it’s cheap, and
comes off under the steam cleaner, if you can’t just flick it off
with a fingernail. Small details won’t stay on, but it’s fine for
larger masked areas, like the entire edge of a ring, or a bezel
sitting on a surface you want sandblasted, or things like that. I
also sometimes just use ordinary masking tape. Not as flexible as
electrical tape, but cheaper, and in our shop, easier to find. I put
a piece of tape down on some flat surface, slice it up with a scalpel
to thin strips, and start patching them on as desired.

Peter

Doug, I always used simple masking tape. It is easy to cut, sticks
like crazy but is also easy to get off. And it stretches a bit when
putting it on curved surfaces which makes it easy to use. have’nt
tried nail polish but may give it a try. And masking tape comes in
very tiny widths for striping, and very wide widths as well. When
I’ve run out of masking tape, I’ve used adhesive tape or even band
aid tapes, but they are more difficult to trim, and the adhesive tape
is a pain to get off.

Kay

Hello Doug, I use Buttercut. It’s an adhesive backed flexible rubber
that is easily cut with a scalpel for very fine detail on flat or
curved surfaces and adheres through heavy blasting. I get it at the
stained glass supply store. Marta

I like using stickers for resists. The trick is to find a sticker
that will have a recognizable shape even when the color is removed,
like hearts or stars, and it must also have been cut out along the
line of the shape. Often they are packaged in clear cellophane so
you can turn them over and see how they work as just a shape.

I also make my own stickers using contact paper and craft punches.
What I like about that technique is that you can create both
positives and negatives using either the punched-out shape, or the
piece you punched it out of, or both.

Linda

Would this Buttercut also be useful in acid etching (used instead of
a typical resist)??

Talia in Kansas

Hi Talia, The Buttercut is a thick rubber that is made to resist the
heavy blasting of sand, I don’t think it’s rated for acid, but I
don’t know for sure, good question. The vinyl resists are rated for
both sand and acid. You can also get nice patterned vinyls at
stained glass stores or websites such as Alpineglass.com (no
affiliation…) that are for a variety of media including metal.
Using a quality resist will give you clean professional lines.

Marta

As you may have deduced, rubbery things tend to work best. In that
spirit, I have also had great success (dependind on the type of
detail you’re after) with rubber cement, Elmer’s glue, and frisket.
The last allowed me to paint detailed tree limbs, though I ruined
some fine brushes by not rinsing them often enough.

–No�l