Do not remove the protective plastic. Mark the window for trimming using masking tape or a permanent marker pen. Trimming is best done using an angle grinder (masonry blade). Do not use a toothed saw. The off-cut must be supported in its original position during cutting. After cutting the edge should be smoothed to lessen the tendency of edge cracking. This can be done using a belt or drum sander, or by hand with a fine sandpaper block (220 grid)
Drills are sharpened to cut metal. Using this type of bit, it is nearly impossible to drill a hole in acrylic without it cracking. When sharpening a drill for acrylic the object is to shape the drill so that it scrapes its way through the material. Best point angle is 120º then, grind off the cutting edges. Practice on off-cuts, with drill running at high speed and a slow feed (light pressure)
Acrylic expands and contracts at the rate of ±3 mm per meter per 24ºC-temperature change. Hole diameters along the edge of a window, should therefore be accordingly bigger than the bolts holding it, and preferable have rubber grommets
Remove the protective plastic from the portion of the window that goes under a fairing or moulding. Leave the rest of the protective plastic on the window to prevent scratches and abrasions. Removing the protective plastic may cause a static electrical charge that will attract dust. Wipe the exposed window with a clean damp cloth to remove the electrical charge. Follow the installation procedure prescribed in the aircraft maintenance manual.
Do not subject aircraft windows to fumes or vapor of paint thinners, or other organic solvents. When painting, windows must be covered and sealed from the fumes. Thinner used for paint or dope, is often the cause of crazing in windows. An open can of thinner sitting in the closed cabin of an aircraft for a few hours is enough to cause severe crazing in all the windows. The damage is not immediately apparent but will show up as crazing in a few days to a couple of months depending on the concentration of the exposure. Paint stripper will destroy a window within minutes.
If there is a little dust, leave it, clean windows only when there is time to do it right. Flush dust from windows with water before wiping or washing, otherwise it turns into a scouring job. These small scratches add up over time and windows become dull and opaque. Wash with a mild dilute soap & water solution and chamois, followed by a clean water rinse (flush all soap away) Flush - wash - flush - chamois wipe Do not use a dry cloth, as it loads the acrylic with static that will attract dust.
When the aircraft is parked outside, do not use a waterproof cover. Moisture condensing between the cover and the window, combined with heat from the sun, will in time turn windows slightly milky, followed by crazing. When the aircraft is parked in the sun keep the cabin ventilated. Closed cabin temperature can easily reach 70 to 90ºC. Thermal cycling has very little effect, but repeated exposures do add up, shortening the service life of windows. Use of reflective sun shields on the inside will significantly reduce cabin temperature. In the hanger, cover windows with a soft blanket through which air can circulate to prevent hanger rash.
The above information has been gathered in earnest and given in good faith.
We cannot be held liable for losses.
Welcome to Aces Plastics, we are a repair and manufacture facility of acrylic windows and fiberglass components for both Aerospace and Commercial applications.
We are a South African Civil Aviation Authority approved facility, our aerospace capabilities include the manufacture of fixed wing aircraft and helicopter windows as well as the manufacture of composite aircraft components. SA CAA MP39.
Commercial applications include the repair and manufacture of racing car windows, golf cart windscreens and boat windows.
All products are manufactured to your specifications with a choice of colours available for windows.
Should you have any queries or require any further information about our products or services, please feel free to contact us.
Look forward to hearing from you!
Cross-section of drill used for steel.
This will dig in, causing cracks
Cross-section of drill sharpened for acrylic.
The drill does not dig in, but scrapes its way through the material.
© 2008 Aces Plastics. All right reserved