Keyguard Materials

Keyguard Materials

Originally published Feb 16, 2017

Keyguard AT offers the greatest number of materials for any keyguard manufacturer.  In this blog we'll help you understand the differences so you can choose the material that will best work for your keyguard users.

Keyguard AT can make a keyguard in any configuration to match any app.  We make our keyguards to match the settings you have chosen in the app, rather than requiring you to set the app to match our keyguard.  Combined with your choice of materials, these options make our made-to-order keyguards truly customizable to a degree our competitors can't match.

PMMA

Polymethyl methacrylate (PMMA) is a common thermoplastic usually called acrylic, and often recognized by the brand names Plexiglass, Perspex, and Lucite.  It is most commonly transparent, though it is available in a variety of colors and opacities.  PMMA is more flexible than glass and tends to crack rather than shatter, making it much safer than glass.   It is laser cuttable, making it perfect for custom keyguards.  Though it can crack under extreme bending, it is plenty strong to withstand normal use and abuse.

Keyguard AT offers clear PMMA in thicknesses of 3/16", and 1/4".  As of 2018, we no longer offer PMMA in 1/8".  See below for 1/8" PMMA/acrylic styrene and polycarbonate.  

Thicker acrylic is much more rigid than thinner acrylic.  Also, thicker acrylic keeps the fingers farther from the screen and helps to prevent false touches.

Acrylic keyguards are often made the same day they are ordered, and are usually shipped within a week when everything is in order.  The only exceptions are when we are waiting on the customer for complete information, when we have high demand for one of the less popular colors, or when we are out of the office for a trade show or conference.

PMMA/Acrylic Styrene (ADA-compliant)

This is a variety of acrylic that is great for making keyguards, and has been our preferred material since early 2017.  It is more than 50% PMMA with a majority of the rest being styrene, a more flexible plastic.  This makes it much less prone to cracking when bent.  In fact, it is so flexible you need to just about fold it over to crack it. 

PMMA/acrylic styrene is designed for signage compliant with to the American Disabilities Act (ADA), which requires it to be non-glare.  As such, it is not quite as clear as standard PMMA.  The manufacturer rates it as 95% transparent.  The screen appears very slightly darker through the acrylic, so little you wouldn't even notice it.  This has a distinct benefit, though, in that it helps to visibly separate the openings a little, unlike the more transparent keyguards which can blend in with the background.

Keyguard AT keyguards made from acrylic styrene come with a two-year guarantee against breakage.  They can be laser cut, so we have the greatest flexibility of design and the usual quick turnaround time.

Acrylic styrene is available in several colors, and more are available on request.  The colored sheets have the same non-glare finish as the clear, and are just as strong. Colored acrylics help the user see the keyguard openings, however, they also obscure what's on the screen. Therefore, colored acrylics should not be selected for apps for sighted users when the software does not provide space between the cells.

Examples of apps with good cell spacing where colored acrylics work well: GoTalk Now, Compass, Proloquo2Go when cell spacing is Loose or Very Loose, and TouchChat or LAMP Words for Life with button margins of at least 10. Examples of apps with poor spacing where colored acrylics should be avoided: TouchChat or LAMP Words for Life with a button margin less than 10, Proloquo2Go when cell spacing is Normal, Compact, or Very Compact.

Colored acrylics are a great choice for keyguards on keyboards and laptops, giving them a fun, personal touch.

Because of its high visibility, high transparency, high strength, and laserability, ADA-compliant acrylic styrene is by far our best-seller.  Our standard turnaround time for acrylic styrene keyguards is a day.

Polycarbonate

Polycarbonate is a thermoplastic polymer of carbonate groups that is extremely strong and durable.  It can be bent to extreme angles without breaking.  It is most commonly transparent, though other colors are available.  As such it is the premium material for Keyguard AT keyguards, and it comes with a lifetime guarantee against breakage.

Polycarbonate is the material of choice for keyguards with long, thin bars of plastic. Keyguard AT polycarbonate keyguards have a lifetime guarantee against breakage! Polycarbonate cannot be reliably laser cut, therefore it is milled, which leaves a slightly sharper edge around the openings than with laser cut acrylics. We bevel that edge at a 45 degree angle to reduce its sharpness.

Polycarbonate keyguards come in thicknesses from 1/16" to 1/4". The 1/8" thickness will be like our standard keyguards.  Use 1/4" polycarbonate when you want deeper holes, and use 1/16" polycarbonate for when you want shallower holes.

When ordering keyguards, choose polycarbonate for apps with no space between the cells, or for cases which don't allow enough room for thicker perimeter bars.  Check  here for information about the most popular cases and how much room they allow for strong keyguards.

Polycarbonate has a shiny, reflective surface which may be distracting for some users.  If you're concerned about glare, you can ask us to sandblast the keyguard.  The example here shows a clear polycarbonate keyguard with the 45 degree beveled edges, our snap-in attachment, a sandblasted surface, and a lifetime guarantee!

Since polycarbonate keyguards require special handling, please allow 3 days for their manufacture.

Printed Polyurethane Acrylate

3D printing is now a viable way of making keyguards, and we expect it to be more capable in the future.  Keyguards can be as thick or as thin as needed.  Resin printing allows us to make any shape we want, with high enough resolution to make rounded corners with a smooth finish.    

Resin printing uses ultraviolet light to cure a liquid resin into the desired shape.  50 micron layers are so thin that the layers blend together into a smooth surface.  The material we've chosen is a polyurethane acrylate that is accurate, strong, and available in gray or black.

Printed Polycarbonate

FDM 3D printing is where a plastic material is melted and then deposited onto a surface in the desired shape.  We've tried all the popular materials for FDM printing like PLA, ABS, etc., and some high-tech ones like nylon, but because of the air incorporated into the material during the printing process, they're just not clear enough or strong enough to compete with our cut keyguards.  The only material we've found strong enough for printed keyguards that we can guarantee against breakage is polycarbonate.  They're not as strong as the sheet cut polycarbonate, so they don't have the lifetime guarantee that does, but they're strong enough to stand up to typical users.  Printed polycarbonate might be a choice for users who would benefit the textured surface or are allergic to photopolymers.

The image above shows a laser-cut PMMA/Styrene keyguard on top of a 3D printed polycarbonate.

Wood

Looking for a classy way to set your keyguard apart from the others?  Keyguard AT makes keyguards out of real wood.  Since they are opaque, they are not suitable for apps without space between the cells.  However, they are great for apps with adequate room and give an executive look to keyguards on keyboards and laptops.

Wood keyguards make a wonderful conversation piece and a unique experience for the user.  Their old-world beauty is a remarkable contrast to the high-tech of the iPad!  Wood also provides a great tactile experience for low-vision users and users with high tactile needs.

Wood keyguards come unfinished.  They are laser cut, so there are no splinters, but light staining enhances their beauty.  We recommend a polyurethane finish.  Minwax Wipe-On Poly Clear Satin is an excellent choice!

Please allow an extra week for wood keyguards.