What only options are fixing the door in position by homebrew not tested! Here is another, perhaps the most accessible of the simplest. You will need only a small piece of sponge rubber (e.g., bath sponges). Attached to the bottom of the door close to the floor, he will hold it in the place where you need.
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The AIRBOAT
RC model aerolaser (Fig. 1) easy to manufacture, and it does not require scarce materials. Do this even for a Modeler with a little experience, and so the airboat could become a learning...
GEAR -SAW…
Somehow I had the need to cut a thin sheet of plastic. Due to its large size, use the hacksaw was impossible, but to cut just the canvas for a long time, and breaks it in his hands....