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All Seasons Glass  carries Acrylic (plexiglass) and Polycarbonate (Lexan) in stock.  We carry  acrylic and polycarbonate  in several different thickness' .  Window repairs using acrylic meet requirements of the federal safety  glazing code for use in hazardous locations such as doors, storm doors and windows next to a door.  Plastics are used in many home decorating projects and are easy to work with using standard woodworking tools. 

Acrylic Facts

Characteristics of the material

Acrylic Plastic

Half the weight of glass

Impact resistant

Unaffected by sun or salt spray

Temperature range of -30 to 160° F for continuous service

Cleaning

Wash with mild soap or detergent, with plenty of lukewarm water, dry with soft cloth or chamois.
Grease, oil or tar can be removed with hexane or kerosene. Solvent residue should be removed by washing immediately.
Do Not Use window cleaning sprays, scouring compounds, acetone, gasoline, benzene, carbon tetrachloride or lacquer thinner.

Masking

When working with the material, leave the paper masking film on the sheet as long as possible. Except for intricate detail work you should remove the masking only when your project is completed.

Working with acrylic plastic sheet

DO
Keep masking on as long as possible. Use metal cutting saw blades and drills which are ground for acrylic sheet.
Make sure all tools are sharp.
Use water or drilling oil as a coolant when cutting sheets over 1/8" thick or drilling sheets over 3/16" thick.
Wet the material before cleaning.

 

DON'T
Use saw blades with side-set teeth. Saw teeth ideally should be ground with 0° of rake and be of uniform height and shape.

Cutting Acrylic Plastic Sheet

Cutting with a knife or scriber
Acrylic sheet up to 3/16" thick may be cut by a method similar to that used to cut glass. Use a scribing knife, a metal scriber, an awl, or a utility knife to score the sheet. Draw the scriber several times (7 or 8 times for a 3/16" sheet) along a straight edge held firmly in place. Then clamp the sheet or hold it rigidly under a straight edge with the scribe mark hanging just over the edge of a table. Apply a sharp downward pressure to break the sheet along the scribe line. Scrape the edges to smooth any sharp corners. This method is not recommended for long breaks or thick material.
Cutting with power saws
Special blades are available to cut acrylic. Otherwise use blades designed to cut aluminum or copper. Teeth should be fine, of the same height, evenly spaced, with little or no set.
Table and circular saws
Use hollow ground high speed blades with no set and at least 5 teeth per inch. Carbide tipped blades with a triple chip tooth will give the smoothest cuts. Set the blade height about 1/8" above the height of the material. This will reduce edge chipping.

When using a hand held circular saw, clamp the sheet to the work surface and use a length of 1x3 wood to distribute the clamping pressure and act as a guide for the saw.

Feed the work slowly and smoothly. Lubricate the blade with soap or beeswax to minimize gumming from the masking adhesive. Be sure the saw is up to full speed before beginning the cut. Water cooling the blade is suggested for thicknesses over 1/4", especially if edge cementing will be performed.

Saber saws
Use metal or plastic cutting blades. The blades you use to cut acrylic should never be used for any other material. Cut at high speed and be sure the saw is at full speed before beginning the cut.
Hand saws
Good results are possible, but very difficult. Be sure the acrylic is clamped to prevent flexing. Flexing at the cut may cause cracking.
Routers and shapers
Use single fluted bits for inside circle routing and double fluted bits for edge routing. At the high speeds at which routers operate it is critical to avoid all vibration. Even small vibrations can cause crazing and fractures during routing.

Drilling

For best results, use drill bits designed specifically for acrylic.

Regular twist drills can be used, but need modification to keep the blade from grabbing and fracturing the plastic. Modify the bit by grinding small flats onto both cutting edges, so the bit cuts with a scraping action. If the drill is correctly sharpened and operated at the correct speed, two continuous spiral ribbons will emerge from the hole.

Finishing Acrylic Plastic

Scraping
The first step in getting a finished edge is scraping. The back of a hacksaw blade is perfect for scraping. Simply draw the corner of the square edge of the blade along the edge of the acrylic.
Filing
A 10 to 12 inch smooth cut file is recommended for filing edges and removing tool marks. File only in one direction. Keep the teeth flat on the surface, but let the file slide at an angle to avoid putting grooves in the work.
Sanding
If necessary, start with 120 grit sandpaper, used dry. Then switch to a 220 grit paper, dry. Finish with a 400 grit wet/dry paper, used wet. Grits as fine as 600 may be used. Always use a wooden or rubber sanding block.

When removing scratches be sure to sand an area larger than the scratch. Sand with a circular motion, and use a light touch and plenty of water with wet/dry papers.

Almost any commercial power sander can be used with acrylic. Use light pressure and slower speeds.

 
Polishing
Final polishing will give acrylic a high luster. Power-driven buffing tools are recommended without exception. Buffing wheels are available as attachments for electric drills.

A good buffing wheel for acrylic consists of layers of 3/16" carbonized felt, or layers of unbleached muslin laid together to form a wheel. Solidly stitched wheels should be avoided.

The wheel should reach a surface speed of at least 1200 feet per minute. Speeds of up to 4000 feet per minute are useful for acrylic.

Acrylic should be polished using a commercial buffing compound of the type used for silver or brass, or you can use a non- silicone car polish that has no cleaning solvents in it.

First, however, tallow should be applied to the wheel as a base for the buffing compound. Just touch the tallow stick to the spinning wheel, and then quickly apply the buffing compound.

To polish, move the piece back and forth across the buffing wheel. Be careful not to apply too much pressure. Keep the work constantly moving to prevent heat buildup.

Never begin polishing at the edge of the sheet. The wheel could easily catch the top edge and throw the piece across the room or at you.

Forming Acrylic Plastic

Acrylic can be heated to make it pliable. It will become rigid again when it cools. Never heat acrylic in a kitchen oven. Explosive fumes can accumulate inside the oven, and ignite.

A strip heater is the best tool to form acrylic. This tool will only form straight line bends. Buy one from your acrylic dealer. The strip heater will heat just the area to be formed.

Heat the sheet until it begins to sag at the bend line. The bend should be made away from the side exposed to the heating element. Sheet thicker than 3/16" should be heated on both sides for a proper bend. Use forming jigs or clamps for best results, and wear heavy cotton gloves when handling heated acrylic.

Forming other than straight line bends will generally require specialized equipment and jigs.

Joining Acrylic Plastic

Solvent cement is recommended for joining acrylic. There are two techniques for solvent cementing, capillary and dip or soak methods.

 

Capillary cementing
This is the most popular method for joining acrylic. However, this method will not work at all unless the parts to be joined fit together PERFECTLY.

Make sure the parts fit properly. Then join them with masking tape or clamp them in a form to hold them firmly in place. It is important that the joint be in a horizontal plane, or the cement will run out of the joint.

Apply the cement carefully along the entire joint. Apply from the inside of a box-corner joint, and on both sides of a flat joint. A needle-nosed applicator bottle is recommended. The thin cement will flow into the joint through capillary action and form a strong bond. Maximum bond strength will not be reached for 24 to 48 hours.

POLYCARBONATE (MakrolonŽ, LexanŽ)

Polycarbonate is a tough, dimensionally stable, transparent thermoplastic that has many applications which demand high performance properties. This versatile thermoplastic maintains its properties over a wide range of temperatures, from -40"F to 280"F. It is available in three types: machine grade; window and glass-filled. It is the highest impact of any Thermoplastic, transparent up to 2" in special grades, outstanding dimensional and thermal stability, exceptional machinability, stain resistant and non-toxic with low water absorption.

Machine Grade is relatively stress free to permit the most demanding machining. It is also available in glass-filled. This polycarbonate is perfect for high performance uses in tough applications over a broad temperature range.

Window Grade is optically clear, providing total luminous transmittance and very low haze factor. The high impact strength makes it resistant to repeated blows, shattering and spalling.

Glass Filled
Glass-reinforced polycarbonate is finding principal applications in designs where metals, particularly die-cast aluminum and zinc, are commonly used. The coefficient of thermal expansion is reduced by nearly 75%, thus equaling that of some metals. While glass-reinforced has less impact strength than standard grades, it is still tougher and more impact resistant than most other plastics and die cast aluminum.

ADVANTAGES TO POLYCARBONATE

Impact strength
Unnotched polycarbonate is virtually unbreakable, making it extremely safe in areas where parts may be exposed to impact. When exposed to repeated heavy blow, the material tends to cold form rather than shatter.

Electrical
Polycarbonate is excellent for electrical applications, because of its high dielectric strength and high volume resistivity which decreases only slightly as temperature or humidity is increased.

Machinability
Parts can be easily machined from standard metal working tools. No special tools are needed, and finished parts can be polished to a high gloss. Water or water-soluble cutting oils should be used when machining polycarbonate, since some standard cutting oils will attack the material. Polycarbonate can be machined on standard metalworking or woodworking equipment. Its unique properties permit it to be machined without chipping, splitting, or breaking.

Bonding
Polycarbonate can be mechanically bonded by standard methods. It can also be cemented by using a solvent such as methylene chloride or adhesives such as epoxy, urethane and silicone. Polycarbonate and also be ultrasonically or vibrationally welded.

Removing paint or other materials
Fresh paint may be removed by rubbing lightly with a cleaning material such as isopropyl alcohol, or VM-P grade naptha. Then the sheet should be washed immediately with a mild soap or detergent in warm water, and rinsed thoroughly with clean water. Grease and glazing compound may similarly be removed from the surface with the above mentioned cleaning materials. Weathered paint may be lifted off the sheet with masking tape. Razor blades or other sharp scraping tools should never be used.

MORE ADVANTAGES TO POLYCARBONATE

Formability
Standard polycarbonate sheet is not heat formable; however, formable sheet is available on a custom basis. Standard Lexan polycarbonate sheet can be heat formed with proper pre-drying. Lexan sheets up to 114" may also be cold formed under special conditions.

Cleaning
Kleenmaster Brillianize may be used. (Also see Novus) Products such as abrasive or highly akaline cleaners, acetone, carbon tetrachloride, benzene or leaded gasoline should not be used, and the sheet should not be cleaned in hot sun or at high temperatures.

Scratch Removal
Craftics 20/20 Plasti-Polish Scratch Remover is often all that is required to subdue hairline scratches and minor abrasions. Any polish, however, should be tested first on a sample area of the polycarbonate sheet.

Decorating
Polycarbonate products will accept painting, printing, or vacuum metalizing as decorating methods.

UV Stabilization
Natural and Black Machine grade and Window grade are UV stabilized. Polycarbonate rod, machine grade, is not UV stabilized, but is available on custom quotation.

 

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6760 North Ridge Rd. West

Geneva, Ohio 44041

440-466-5775

ŠAll Seasons Glass 2012