Picture of Recycled Plastic in Plane Design
Using plastic shrinkable (PET) bottles to craft an aerodynamic and pleasing to the eye, engine cowl on a model aircraft.
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Step 1: Design Thoughts

Picture of Design Thoughts
Once you have the basic fuselage its time to figure what motor you're going to be using and how its going to be mounted. Once thats taken care of, then you can begin with the cowl.

Points to consider:
Streamlined for aerodynamic considerations

Blend in with the fuselage

Have some vent holes for oncoming air to cool the motor.

In my case Im using an electric speed 400 which can get hot if totally enclosed, so I need some air flow past the prop and an escape outlet in the fuselage to prevent pressure buildup, which might cause the covering to balloon.

Step 2: The Shrink Process

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This is basically how to shrink a plastic bottle over a mold with a heat gun.

Start by cutting off the bottom and inserting the wood plug.

I'm using a 2L milk bottle for a demo, so its way too big for the plug, but its just to show the procedure.

Next shrink the bottom of the bottle first to trap the plug inside. Then do the neck area, here I've cut off the threaded part to make the shrinking neater and easier.

One you're happy with the entire look its time to let it cool and the trim the waste so as to pop the mold off the plug.

Step 3: Time for the Test Plastic

Picture of Time for the Test Plastic
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Give a general description of the Step
The bottle of choice is a 500ml PET type. First I made a wooden plug to shrink the bottle around and then I did a test shrink with clear coke bottle.

Also, I made the plug slightly larger than the fuselage so that it could be slipped on and taped in place.

Some practice is needed with the heat gun to stop bubbling and white-out.

I also gave the wood plug a few wax coats to make it easier to pull the mold off.

Step 4: Final Choice and Shrink

Picture of Final Choice and Shrink
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I chose a transparent blue bottle to match the rest of the plane's color scheme, preferably something without dimples in it.

Fixing the cowl on with sellotape is easy to remove if needed but otherwise sticks well.

There was lots of standing back and checking the appearance and of course admiring the handy work. :)

When it looks right and feels right then its time to stop.

Incidentally the plane is a 440 gram park flyer.
Speed 400 aerobatic plans at Flymodels UK

edballjones5 years ago
this is a proper plane i will eat it later
buenos apetitos
*cough. what?
DemeGeek6 years ago
Would it be possible to make the rudders use via remote control or would that be too heavy?
petercd (author)  DemeGeek6 years ago
sure, with another micro servo, but a waste of time and money. Its not necessary because the plane can be flown well enough on elevator and ailerons alone.
mtm1010976 years ago
nice plane!!! what technique did u use to cove the fuselage? yours looks so much better than mine X(
petercd (author)  mtm1010976 years ago
Thanks, its the ultra lite version of the shrink film, after 6 planes you tend to get the hang of it. :)
emdarcher6 years ago
where did you get the airplane plan or layout? what model?
Hello I'm also in to rc flying, Is this the plane from www.flymodels.co.uk?
petercd (author)  Rick make sit6 years ago
Yep, I posted the link to the plans in Step 4.... .... Incidentally the plane is a 440 gram park flyer. Speed 400 aerobatic plans at Flymodels UK near the bottom of the page.
zwild1 petercd6 years ago
Great looking plane! I noticed the electronics on the website were a bit outdated- what kin of geartrain did you choose?
petercd (author)  zwild16 years ago
Also a geared 400. :) A brushless is about 6X the price of the 400
Dave476 years ago
Very cool, I think this could work for ballistic nose cones for model rockets as well as dovetails. Thanks for the inspiration!
Ohm6 years ago
Good old school trick, have you tried making canopies this way, just have to have it go alone one of the sides and have a filler block to take up space.
Great idea! And I'm sure the technique is of much more general use than just in model planes. But sweet plane too.
Didrtan6 years ago
I wonder if you could mold the plastic over the wooden frame of the body the same way you did the nose for the wings you would need a larger bottle
petercd (author)  Didrtan6 years ago
It would most likely add too much weight to the plane, that is if it didnt crush it when shrinking, also assuming you manage to find a 1metre long plastic bottle. On the other hand, if you just wanted an ornament, you could shrink bottles over a wooden form and then cut them neatly in half and glue the shells together again.
cool!6 years ago
Nice instuctable. P.s. brushless outrunners are cheap, durable, lite, and no gearbox. You should get one.
thats awesome. ill ad it to the group
omnibot6 years ago
That PET-nose should add some well needed crash-resistance. Good on you.
dkfa6 years ago
Yea...this is only a 1/4 of a plastic bottle in the front. Nothing else is made of plastic, just wood. Not really a great entry for the contest.
noelle_tan dkfa6 years ago
true that, there are great plastic bottle instructables I've seen that aren't even in the contest
wenpherd6 years ago
omnibot6 years ago
At first I thought the whole plane was done in PET .. silly me. Still really cool though.
yeah your not the only one
me too
that's a great plane! how does it fly?
canida6 years ago