Introduction: Acrylic Trohpies: Cutting, Polishing and Etching Acrylic
What You'll Need:
Table saw or other tools that have the ability to cut a clean, sandable edge on acrylic
120, 220, 360, 600 grit sandpapers
Access to Adobe Illustrator for creating logos and decals
Access to programmable laser for etching logos and decals
Teachers! Did you use this instructable in your classroom?
Add a Teacher Note to share how you incorporated it into your lesson.
Step 1: Cutting a Template
So the first step is to acquire stock material to work with.
I had access to a large slab of one inch thick acrylic. I started by cutting out the rectangular blocks in the sizes that I planned to make the trophies. The featured example here is 3 inches by 6 inches.
I experimented with two methods for cutting the acrylic: laser and table saw. Both will get the job done, but the laser leaves a rougher edge that requires more sanding before a glass- like polish can be obtained. It may be possible to mitigate this roughness by altering the laser's settings, but I have limited experience with the laser.
For this reason, I suggest using a table saw to cut acrylic, especially, if you desire a clear, transparent edge from the polish.
The two above images show the different cuts.
The laser cut edge has the black, burn residue on the protective film. The laser effectively melts the acrylic, and air pressure blows out the material. This leaves a glossy, yet rough edge behind.
Step 2: Sanding the Edges
To prepare the acrylic for flame polishing, I worked the edges through a progression of sand papers.
In order, I used 120, 220, 360, and 600 grit sand papers.
I taped the sand paper down to a flat surface and ran the acrylic block over the grit until smooth. This is shown in the image above
I found that a minimum of 600 girt sand was necessary to create a clear, transparent edge through flame polishing. It may be possible to acquire a transparent edge through finer, physical polishing as well, but I did not experiment with this.
The acrylic block before flame polishing is shown above.
Step 3: Flame Polishing the Acrylc
Creating a transparent edge after sanding isn't too difficult.
The process is simple; the flame from a torch is run along the sanded edge. This will melt the acrylic, effectively removing any surface roughness, leaving behind a clear edge.
Important: It will require some practice though to get comfortable with the speed that the flame needs to be passed along the edge. I found that 3 inches per second seemed to work well. However, this depends on the size of the flame and the thickness of the acrylic. If you move too fast, the acrylic won't glass over. If you move too slow, the acrylic will begin to burn and the edge will fog over. There is a happy medium that takes practice to find.
Warning: Acrylic is flammable. Don't hold the open flame to it for too long. Safety First!
The edge after polishing as well as a video featuring a run with the torch is shown above.
Step 4: Etching the Acrylic
The first step to etching is creating and sizing a decal that will fit on the trophy.
To create the decals, I used Adobe Illustrator. This software is very versatile, and prints directly to our laser software for etching.