i was told that you mite know how to make a fuel tank from a film can
Yup, there's several methods: One of the most reliable and simple is to use a floppy balloon 0common party balloon) as a fuel bladder (non-pressurized) and the film canister as a receptacle for it, just cut a hole in the lid for the fuel line.
Or, you can make a "hard tank" with a canister that has a tight-fitting lid (they vary, check several for the tightest). I use alum. tubing through snug-fitting holes in the lid, "goop"ed into place. Let the Goop cure for a few days before exposing to fuel. I've also made a "clunk-tank" type, using small surgical tubing inside the tank, with a wheel collar on a short piece of alum. tubing for a clunk.
Let me know if you need more detail.