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The drawing below indicates the canopy trim line. Attachment 1 (2 pages) is quite a few words from our canopy subcontractor, Crowley, Inc. on cutting and caring for your canopy. This information is a supplement to the Quickie Plans, Chapt. 15. 7/july/1978
CARE AND FEEDING OF YOUR QUICKIE CANOPY - COWLEY IND.
Now that you have your canopy what are you going to do with it? You can place it between two chairs and sit under it making engine noises and logging time, but it is really why you bought it?. Sooner or later you are going to trim the
monster and that can be a very harrowing experience the first time.
There are two tools you can use without going to a lot of expense and time building a cutting fixture. They are both very useful on the rest of the aircraft. The fastest is a rotary grinder - 1/4 hp, single speed is adequate and available at Sears and other stores. With the rotary use a cut-off wheel, preferably 2 inch diameter, 1/4 inch shank and 1/16 thick. This thin a cut-off wheel is hard to find, try the industrial supply shops. The other good tool is any Dremel tool with a saw blade. Always use a fast speed and don't push,
let the tool do the work. When you cut plastic the chips really fly so use a face shield. A bit of plastic in the eye is very hard to find, even if it feels like a boulder. Don't even consider a saber saw for plastic. If you do manage to trim a canopy with one, without a disaster you are very lucky.
Coat the canopy with SprayLat or mask well. Use masking tape to mark your cutting line well per plans. It doesn't disappear in a cloud of plastic chips as easily as marking pen or grease pencil lines. If you are using SprayLat put it on the canopy thick about a day or two before you plan to trim so it can cure. DO NOT try to cut a cold canopy. It is almost certain
you will have cracks in the wrong places as they fracture very easily. Bring your canopy into a warm room, about 75-80 degrees and give it a few hours to warm up to room temperature before you start trimming. Plastic is slow changing temperature so don't rush it.
Place the canopy on a large flat table, bubble up, with three or four 2 x 4's crossways under it so the whole thing is supported level a bit off the table. Keep it this way the entire time you are working and trimming on it so you don't accidentally twist or stress it in some way. The cut should be made with the cut-off wheel or saw blade just barely deep enough to completely cut through the plastic.
The point at which the side turns toward the nose is the most delicate part and subject to fracture because of flexing outward. This can be prevented by taping gently across the bottom with duct tape. Don't pull the tape real tight, but do have the tape tight enough across the bottom so it doesn't
spring out when pressure is eased at that point. This is the place to start your trimming on the flange just a bit toward the rear of the turning point work parallel to the bubble on up toward the nose of the canopy and straight on out to the edge of the flange. You have actually cut off a triangle. Do the same thing to the other side. Be sure the canopy is steady
and does not vibrate as you cut. Next trim off the entire side flange, one side then the other. The last part is to trim off the back bubble. Have your masking tape around it and at the correct angle as per Plans. Use duct tape across the bottom, just before and just after where you are planning to cut so the canopy can't spring out. The center top is a good place to start. Cut two or three inches down one side and put a strip of tape across the cut. Work from the center down a few inches at a time on one side and then the other side and tape the two pieces together as you go so the two halves can't spring apart and split. Hopefully you now have a trimmed canopy.
A file and sandpaper on the edges will smooth them up nicely. Work your way from coarse to fine sandpaper so all your cutting marks and rough places are gone and the edges have a slight radius. Be sure the canopy is well supported while you are working on it, and do not allow it to flex or chatter or
vibrate. Sand the area where the glass cloth and epoxy will be and you are ready to do the framing lay up. Anytime you are working on the canopy especially if you are going to be flexing it have it in a warm room.
If a crack does start stop drill it immediately. Be sure you drill at the end of the crack or it will keep on running. A new canopy does not deserve a nice new drill. Use an old dull drill or make it dull by filing off the cutting lip vertically. Don't push the drill, use a high speed and let the drill scrape it way through. A small piece of wood held lightly on the back side will help.
Masking tape and plastic left together for several weeks become one, so remove your masking tape. If it is stuck good, lighter fluid will help part the two and get the gooey off. SprayLat does not need to be removed as long as it is not stored in the sun over a prolonged period of time.
There are many good plastic cleaners and polishes on the market at auto supply stores. Use a soft cloth like flannel and do not wipe dust off of the canopy. It will scratch. If the canopy is very dirty rinse it off with water first and then polish it.
Have a happy time building and flying.
Cowley Ind.
Mojave Airport, Bldg. 170
Mojave CA. 93501
Phone (805) 824 2368
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