Flame Polishing Acrylic - THO Game Calls

Flame Polishing Acrylic

By Brian Byers of Byers Custom Calls
Flame polishing acrylic is a technique that can be used to polish acrylic to a glassy shine. It can be a little
bit quicker than polishing acrylic with sandpaper and polishing compounds.
I turn the barrel to final shape and sand to 400 grit

Next, you need to clean up the area around the lathe, and vacate the area of anything flamable. We will
be polishing with a torch flame, so make sure there is nothing flamable around. Now is also a good time
to locate the fire extinguisher too.

Here is my setup. It is a Little Smith jewelers torch. http://www.littletorch.com/ I use a #4 tip, and also
have the 3" extension installed on the torch. For fuel, I use propane and oxygen.

The tip size does impact the size of the flame, and the flame size impacts the ease of polishing. Here is a
size chart of tip sizes and flame sizes that are available for this torch.

You'll have to experiment with the size of flame that works best for you.

The goal is to go accross the barrel as smoothly as possible without stopping. You'll notice that there
starts to get a flame that wraps around the barrel towards the end. If this happens, the heat is getting
too excessive and is starting to burn the acrylic rather than polishing it. I got lucky and it didn't burn it
and was also lucky to start the polishing again without any transition lines from where I left off at.

I let the call continue to still spin on the lathe, and cool down for a few minutes. I keep the lathe
spinning when doing this, because the cast acrylic will be quite warm, and will want to droop and
deform if you stop the lathe. Thin sidewalls on a barrel will really want to deform badly.

Once it has cooled down, I'll work in a bit of polish on the barrel for a final polish, and then remove it to
cool completely.

Here is the final result.