Acrylic

From ProtoLab Wiki
Acrylic Samples

About Acrylic

Poly(methyl methacrylate) (PMMA), also commonly known as acrylic or plexi-glass is a transparent thermoplastic often used in sheet form as a lightweight or shatter-resistant alternative to glass. The Idea Shop stocks acrylic in following thickness and respective colors:

0.0625" (1.5mm) Acrylic
white, black
0.125" (3mm) Acrylic:
opaque red, transparent red, clear, orange, yellow , white, black, opaque blue, transparent blue
0.25" (6mm) Acrylic
glass texture, clear, white, black


The IdeaShop offers ACRYLITE® products.

Working with Acrylic

Acrylic can be used in many different ways and can be formed into different shapes and sizes. Depending on the scope of the project you either need to just use a laser cutter to cut your geometry or use a combination of methods listed below to fabricate your design.

Engraving

Acrylic Samples

Engraving is the process of incising small groves of patterns or shapes onto a hard surface. This process can be used to easily personalize items and imprint a specific drawing or sketch on an acrylic item. The easiest way of engraving is using the laser cutter, since it is designed for engraving and cutting material. In order to engrave your parts, open your geometry in AUTOCAD and select the desired areas. Next, in the layer selection menu, select raster (represented by red color) and follow the rest of laser cutting process, explained here.

Cutting

There are may ways of cutting acrylic. For assistance deciding how to work with your acrylic, consider the size.

For a cut length that fits inside a 24" by 18" box
The Laser Cutter is the ideal tool to use. Be sure to select the appropriate material settings to achieve the desired cut.
The Bandsaw is also a good alternative when the laser cannot be used, such as if the acrylic is too thick. The band saw can follow almost any cut geometry, ideal for small parts. Note that the band saws cut quality and accuracy depends on the user; the laser cutter is the most accurate choice.
If the cut length is bigger than 24" by 18" then there are a couple of options listed below
The Panel Saw is only ideal to make straight cut lines.
If the part you are trying to cut also has intricate geometry, consider the ShopSabre.

Adhering

Adhering acrylic can be a tedious task and requires lots of patience. Methods to adhere acrylic are listed below:

Using acrylic solvent

Note: always wear surgical gloves before working with acrylic solvent. Its is also a highly flammable substance. Acrylic solvent is low viscosity transparent fluid that will bond and dissolve two sections of acrylic permanently. The two bonding pieces must be held securely together using clamps or a jig. Once secure, acrylic solvent can be applied on the bonding surface. Because of the low viscosity, it is easy to make a mess and use too much solvent on the bonding surface. Make sure to not use your hands or anything else to dab away the excess solvent, as it may imprint the material texture on the surface of the acrylic. In a situation where there is excess solvent on the bonding surface, use a paper towel and place it in contact with the solvent, not the acrylic surface, and wait for the paper towel to absorb the excess solvent. The curing time of bonded pieces varies depending on the size and shape of the bonding area. The pieces that are being bonded together must be held in place for at least 5 mins before letting go. Allow a minimum of 12 hours for the solvent to cure before exerting load on it. Use of excess acrylic may leave a frosty texture around the bonding surfaces.

Using superglue

Note: always wear surgical gloves before working with super glue. The IdeaShop stocks two varieties of super glue, one of high viscosity and one of low viscosity. For bonding surfaces which have many crevices and inlets, use low viscosity. For bonding external surfaces, use high viscocity. The two bonding pieces must be held securely together using clamps or a jig. Super glue requires 2-3 mins to dry and should be given a minimum of 2 hours before exerting loads on the bonded parts. Unlike acrylic solvent, it is difficult to clean off excess super glue without altering the finish of acrylic. Using isopropyl alcohol to clean off excess super glue will help, but will not completely remove all of the glue. If excess superglue is used to bond acrylic surfaces it will leave a "frosty" texture around the bonding surfaces.

Vacuum Forming

Acrylic can also be used for vacuum forming molds. To vacuum form, you must have at least a 12" x 12" sheet.