Plexiglass vs Lexan Matchup

I don't know how many times we have been asked the question - What's better: Plexiglass or Lexan?

Depends. What's the application? Let's match up some KEY properties to see:

Plexiglass (acrylic sheet) aka Lucite, Plexiglas, Perspex, Acrylite

• 92% light transmission - clearest plastic sheet available - about 15% cheaper than polycarbonate
• large variety of colors available 
• light pipes through the sheet edges
• does not yellow or discolor in the sun - 10 year warranty regarding 2% loss max.
• optically water clear in all thicknesses
• inert - no outgassing
• thermoplastic - working temp of 180F continuous
• burns very nicely after you remove a flame source - fire rating UL94HB
• scratches - can be restored by sanding and buffing
• resistant to breaking - when breaks pieces are large and dull edged
• recyclable
• easily bonds with solvent adhesives to itself and other plastics
• hydroscopic (will absorb a small amount of moisture on side facing moisture (warps)
• available up to 4" thick as a monolithic cast sheet, and thicker via custom casting

Lexan (polycarbonate sheet) aka Tuffak, Makrolon

• 88% light transmission - very clear - about 15% more expensive than Plexiglas acrylic sheet
• limited colors available (white, black, bronze, gray, sign colors)
• light does not pipe through sheet edges
• untreated sheet discolors in 5-7 years of sun exposure - UV coatings available to extend 15 years
• inert
• optically clear - loss of some light transmission in higher thicknesses (5% in 1/2")
• thermoplastic - working temp of 275F continuous
• self-extinguishing fire rated 94V0 - UL rating depending on thickness
• scratches - cannot be restored by sanding and buffing
• resistant to breaking (virtually impossible to break)
• recyclable
• easily bonds with solvent adhesives to itself and other plastics
• bullet resistant grades are available - all grades of BR levels
• hydroscopic (will absorb a small amount of moisture on side facing moisture (warps) and therefore difficult to thermoform without pre-drying
• available up to 1/2" thick as monolithic extruded sheet, up to 2" as a molded sheet

Applications:


Plexiglas Acrylic Sheet:
Safety glazing (up to 17 times stronger than glass)
Boat windows and hatches
Machine Guards and Electrical covers
Display cases
Brochure holders
Picture Frames
Lighting
Anywhere you need a clear, impact resistant, easy to cut and maintain sheet

Polycarbonate Sheet:
Safety glazing (unbreakable)
Bus Windows
Machine Guards and Viewing ports
Anywhere you need a clear, unbreakable, high working temperature, easy to cut sheet

Now you're armed and dangerous - so when you talk to your plastics professional, you can ask great questions about your needs

Plexiglass Wine Rack project

Now THIS is cool.

Our portion of this rack is the central core of clear and frost Plexiglas acrylic sheet along with the cast acrylic tubes used to hold the wine bottles.



This rack was fabricated from 1/2" thick clear acrylic sheet on the outside layer, and then the same thickness of Plexiglas Frost acrylic sheet.

Holes were routed (by hand) into the inner and outer layers to support the clear cast acrylic tubes that will hold the wine bottles. This tubing has a 3/8" thick wall.






Let's look closer at the tubing used:

Cool Plexiglas Project - Ronald McDonald House Charities of KC Heart Wall

 

Cool Plexiglas Project - Ronald McDonald House Charities of KC Heart Wall

Hallmark decided to order some colors of Plexiglas sheet and then laser cut these shapes as part of a beautiful program in Kansas City.

Plexiglass Seats in Swimming Pool

So we got a call from somewhere in Alabama where a pool is being built... and in this pool will be "sunken" seating around a clear Plexiglas table. The seats will be plexi and lights will be placed underneath. We understand that the machined areas of these seats will have mosaic tiles place in them.


Very cool.




Here's the machining in process - these disks are about 12" in diameter and 2" thick!

Stay tuned for pictures of the actual pool later this summer....

Another Price Increase for PVC, HDPE, Polypropylene, Starboard

Due to resin and chemical shortages, PVC, HDPE, Polypropylene, Cutting Boards, and PVC Foam board were hit with increase of 6-10% this week.

On July 15, all Plexiglas and acrylic sheet products will be hit with a 8% increase nationwide.

At least these materials are all made in the USA - keeping jobs here in the states.

Cutting Plexiglass Makes Art

This is a quick post - sometimes you catch the shop after they have cut different colors. The layers fall to the floor under the table saw - it's random and cool. Enjoy. Looks like a dessert!





Or the simplicity of cutting 1 color of plexiglass - in this case 2793 red. When you are cutting plexiglas, it leaves a pile of chips - not dust.

They drop to the floor from the table saw, and scatter like a snowdrift from the table router.

Clear Plexiglass Car up for Auction

Courtesy of http://www.boingboing.net/

This beautiful, skeletal Pontiac was built for the GM pavilion at the 1939 New York World's Fair. It's up for auction in Plymouth, Michigan, with an estimated sale price of $275,000 - $475,000.

As of yet, RM doesn't have any detailed information about the Pontiac, but from an article in Special Interest Autos #34, we see that GM built two - possibly three - transparent cars for the New York World's Fair of 1939-1940, one of which was a Deluxe seven-window touring sedan (B-body), the other of which was a Torpedo five-window touring sedan (C-body)...

Visitors to General Motors' "Highways and Horizons" pavilion at the 1939-40 New York World's Fair came away awed by a vision of the future. The work of renowned designer Norman Bel Geddes, GM's "Futurama" exhibit foretold the communities and transportation systems of 1960, many of which came to pass. Other peeks at the future included "Previews of Progress," inventions that seemed like magic: "Yarns made of Milk! Glass that bends! The Frig-O-Therm that cooks and freezes at the same time! The Talking Flashlight transmitting speech over a light beam!" exclaimed the exhibit's guidebook. Sharing top billing with the Futurama and Previews of Progress, however, was the "'Glass' Car - The first full-sized transparent car ever made in America."

Courtesy of http://www.boingboing.net/

Career in Plastics. Sure thing!

Gotta love historical pieces on the Plastics Industry.

Read and enjoy!

Installing Multiwall Polycabonate on my trellis

This is a post in process. Pictures forthcoming.

This week I have a project in my OWN backyard as I will attempt to install some 6mm clear multiwall polycarbonate on a trellis structure. My wife has been asking for this for at least 2 years. I have run out of excuses.

OK - we're in San Diego. I don't have wind, hail, tornados, lightning, hurricanes, or fireflies to worry about.
Basically, sun, 8 inches of rain, bees and what ever is growing up the trellis posts.

So I picked the clear multiwall sheet as the trellis already throws enough shade. I hope I can walk on it to clean the 2nd story windows? Maybe I will make special "snowshoes" to walk on it.

I had to locate and cut square holes to allow the decorative elements to pop through. I am sure the rain will probably pour through there too. Whatever.

I just gave the drawing to the cutting room at Ridout Plastics. It was crude, but I needed to test them.

Update 6/13/11:
Well, I learned that it's a 2 person job to try to install these panels. I installed most of the panels, but need another set of hands to help engage the sheets into to U-Channels

New Plexiglass Adhesive Glue - WeldOn 5

It's baaaaaack. A medium to slow setting solvent adhesive for Plexiglas. Better strength bonds, better looking bonds, better results.

This water thin adhesive is a medium setting solvent adhesive for acrylics (Plexiglass). Will bond other plastics - ABS, styrene, butyrate to themselves. Contains Acetic Acid. For production shops only. NOT recommended for DIY.

Not for use in LA, Orange and Riverside counties in California.

Infrared and Ultraviolet Transmission in Plexiglass Acrylic and Makrolon Polycarbonate Sheet

Well, this explains everything. I finally got my hands on the charts to show UV, Visible, and IR light transmissions in Plexiglass sheet. And, I learned something new today: IR or InfraRed light varies in transmission logarithmically depending on the thickness of the Plexiglas sheet. And, it's not a smooth curve. There are areas of filtered transmission. This explains why the IR remote on my entertainment center works like a champ on the TV and DVR but sucks on the audio amplifier (which has a different IR band). (I am using frost acrylic) (update 8/11 - replaced the panels with the IRT acrylic - it's opaque black but the IR bands are all working for all the equipment!!)

Before sharing the charts, let's think about UV and IR and visible "light".
1. You cannot SEE this type of "light".
2. You can feel the IR - it warms you up.
3. You can't see or feel UV, but your skin will fry if exposed too long, and paper, artwork, fabrics, and other materials will degenerate from exposure.
4. IR is heat, and we can capture heat images in a CCD or IR film - way cool to see.
5. IR can penetrate opaque material. UV cannot.
6. Visible light transmission through clear Plexiglas is 92%. You cannot detect the 8% loss - it looks clearer than water. You lose 4% reflected off the front surface and 4% off the INSIDE of the back surface. If I put a business card at the end of a 4" thick piece of Plexi 8 ft long, you could read it perfectly.

OK - the charts - check this out!

Your UV and Visible Light chart - you can see the natural drop of UV filtering from standard Plexiglas, and then the extra filtering of the UVF and UVT grades. Plexiglas MC is your standard general purpose extruded  sheet, and Plexiglas G is cell-cast acrylic sheet. Plexiglas UF5 is the standard extruded "MC" with a UV filtering additive. UF3 is the version from "G" cell-cast acrylic.

Now the IR light transmission for CLEAR Plexiglas:

According to the makers of Plexiglas®:

INFRARED TRANSMITTANCE
Colorless Plexiglas® sheet sheet transmits most of the invisible near-infrared energy in the 700 to 2,800 nanometer region, but it also absorbs certain bands as shown. The curves for 0.118 inch and 0.944 inch thick colorless Plexiglas® sheet show that near-infrared transmittance depends on thickness, decreasing logarithmically as thickness increases.

At infrared wavelengths longer than 2,800 nanometers and as long as 25,000 nanometers, and in thicknesses greater than 0.118 inch, colorless Plexiglas® sheet is entirely opaque. At thicknesses less than 0.118 inch, Plexiglas® sheet transmits small amounts of infrared energy at certain wavelengths within this region. All standard formulations of colorless Plexiglas® sheet have the same general infrared transmittance characteristics.

Sensitive instruments confirm that weathering produces no change in the infrared transmittance characteristics of Plexiglas® sheet.

But wait, there's more! Here's the special grade of Infra-Red Transmitting sheet. It is BLACK in color, but allows the IR to transmit through. Very cool for spy related video equipment. Available in 1/8" and limited amounts of 1/16" thick.

1146 is the IRT and 199-0 is opaque black. They look identical but obviously are not....

But wait.... there's more!

Here's the chart for POLYCARBONATE sheet - known as Lexan, Tuffak, Makrolon etc.  Note that polycarbonate goes opaque in the UV spectrum and has good IR transmission.

Price Increases for Plastics - Plexiglass, Lexan, HDPE, UHMW and more

You have seen it at the pump. We see it at the plant! The price increases for plastics just keep on coming with no relief in sight. After implementing 6% price increases for acrylics (Plexiglas, Optix, Acrylite, Perspex, Lucite etc.) this month, I received a note today to prepare for a salvo of 8% increases by end of March. And more on the near horizon.

This relates to PLEXIGLASS acrylic sheets - material with a chemical name of polymethyl methacrylate or PMMA.

What the heck is going on? Worldwide supply of the base chemicals needed in the plastics industry are in SHORT SUPPLY.

The economies of China and India are fueling this DEMAND for PLASTICS and associated chemicals. The largest auto markets in the world are there. And of course, manufacturing plants that use the chemicals that produce the sheet, rod, tube and film... that are consumed in those countries!

The world economies continue to change.

Our suppliers tell us to brace for more increases throughout 2011. "Substantial increases".

Probably a good time to purchase that plastic you were budgeting since next month it's more expensive.