Etching Glass With a Sandblaster

I play for the scenario paintball team Pub Crawling http://www.pubcrawling.org . We have more than 20 members on the team and with a name like Pub Crawling we tend to enjoy a drink now and then. 

But having a finely crafted ale out of just any old pint glass simply won't do.  Nor would it be appropriate to drink a $90/bottle of Scotch from a Dixie cup.  To truly appreciate a beverage it should be served in the proper vessel.  Stepping it up a notch by having that vessel custom engraved can add a touch of class to the occasion.

This is different than chemical etching glass that you see quite often.  This method of etching it much deeper in the glass, as much as 1mm in some areas.  You can see and feel the difference in glass depth with sandblasting, chemical etching always gave me lackluster results.

It is assumed that you have some mechanical and computer knowledge.  Not that there is a lot of difficult tasks involved but you will need to know the difference between vector and raster based artwork.  It will also be hand to know how to operate your air compressor and the basics of a sandblaster.

Tools:
Computer with vector art software (Adobe Illustrator or Inkscape)
Vinyl Cutter
Air Compressor
Sandblaster
Utility knife or xacto knife
Squeegee or credit card

Materials:
Vinyl
Application tape
Sandblast media (I use Aluminum Oxide 80-90 grit)
Painter's tape
Glass substrate (Mug, pint, shot, scotch, glass)

First you need to prepare your image and create a vector file for the vinyl cutter.  The ins and outs of how to use something like Illustrator or Inkscape are far beyond the scope of this Instructable.  But essentially the path you create in your vector file is the same path the cutter will follow on the vinyl.  So keep that in mind as any overlapping lines will create extra cuts that you might not need or want. 

Once you have your image complete you need to send it to your cutter.  Again this is specific to your cutter and editing software.  This will send the basic instructions of what paths to cut.  Depending on your type of vinyl you may need to adjust cut speed, feed rate, depth and offset.  It is good to experiment with the vinyl before hand to find out what settings work best for you.

Wait for the cutter to follow the paths and cut the image in the vinyl.  When the cutting head is done use a knife to cut the final image off from the roll.

There are two ways to do this step.  You can either weed the image first and then apply it to your glass.  Or you can apply it to the glass and then weed the image.  I will show the weeding and then applying method here.  Both methods take about the same amount of time and it is totally based on preference.

Use your Xacto knife to carefully remove the area to be sandblasted, leaving the background to act as a mask.

Apply application tape to the top of the image.  This layer will be used to hold the decal together when you apply it to the glass.  Use a squeegee or credit card to smooth it out and push out air bubbles.

Take the time to clean your glass with some soapy water.  Make sure to rinse them thoroughly.  This will remove any grease or oil and help the vinyl stick better.  I do want to point out that I got these beer mugs at the Dollar Store AND they were made in the USA.  That seems almost unheard of to me, and for $1 I'm not complaining.

After your glass is cleaned slowly remove the backing from the vinyl sticker and apply the sticker to your glass.  Take the time to put it on straight and square.  After the sticker is applied smooth it out and push out any air bubbles with your squeegee. 

Slowly peel away the application tape, peeling it at an angle helps as well.  This should leave only the decal on your glass.

After the decal is applied use some masking tape to mask out any nearby areas that may get hit by over spray.  If in doubt simply mask the entire glass.

Your sandblaster may have different directions than mine.  But there are some basics that are fairly common.

Make sure that your air compressor has a moisture separator on it.  Any moisture in the sand and it will clump up.
Make sure your air compressor can output at least 90-100psi.
Only use silica free sandblast media, breathing in beach sand, play sand, and silicon carbide can cause Silicosis.
If you don't have a sandblasting cabinet wear a face mask and goggles (two sets of goggles if necessary) or a sandblast hood.


Without a cabinet the sand gets everywhere.  On every inch of your both, in every pocket, crease, and crevice.  Really it makes a huge mess so do this outside.  If you wear prescription glasses put a pair of goggles over them.  The sand will etch/scratch everything it comes in contact with, including expensive prescription glasses.

Take your sandblaster, point it at your target and start blasting away.  Focus the sand towards the center of your image as much as possible.  The sandblasting media will bounce off from the vinyl and masking tape but will cut into the glass.  The longer your blast the glass the deeper the etching will go.

After you have finished blasting the glasses remove the tape and vinyl resist.  You should be presented with a very cleanly cut glass with a nice deep etch.

It is important to wash the glass before use as there will be residual blasting media dust all over everything, yourself included.  In fact, go take a shower because you will find sand in place you didn't know you had.

Enjoy your glass with a nice frothy beverage of your choice.  I recommend a nice homebrewed beer. 

From your friends at Pub Crawling