My DIY plastic frame bag.

The Great Pacific Garbage Patch will probably fill the whole stinking ocean on of these days, so why not use the plastic instead of dumping it? (To be truthful, I bought new plastic bags to this specific project as I did not have enough them at home so this is not so ecologic as it could be, but you get the idea).

So, I needed a frame bag to my fat bike, and as waterproof/resistant fabric is quite expensive thought of making one from laminated plastic. I had previously done some DIY ass savers and fenders from laminate, so I figured it could be possible. Now, the first attempt was an utter failure, but I tried a new method, made a small handlebar bag and proceeded to make a full-sized frame bag.

Now, the instructions of making plastic laminate can be found by googling, so I do not write them here, except that laminated pieces are easy to sew, and one can actually weld the seam with hot iron so it does not leak. Also, the laminate tends to deform when it is heated, so I laminated the pieces between 2 baking papers and when the laminate was still hot, I quicky put a glass shelf and some pressure over it and let it cool.

Oh, and OPEN THE WINDOWS. The fumes of melting plastic cannot be good for health.

The ingredients of my hideous creation were: laminated plastic, some spare plastic bags, baking paper, cardboard, iron, straps, d-links, some velcro, a zipper and alcohol (the last in order to make my thougths flow more freely).

After I had laminated enough plastic, I made a cast from cardboard. The measurements are quite close to Revelate Design's frame bag [bows to that direction] although mine is a little narrower at the front and wider from the rear. I could have made it a little wider as laminate bag does not bulge very much.

A picture of the cast. Note that one should not use gorilla tape/jesus tape/roadie tape as it melts into plastic, and that's not good (I noticed that when it was almost too late):

Next I cut laminate to appropriate-sized pieces and started plating the cast. I had an old iron which is heated on a hotplate, so there were no wires into which trip myself, but keeping the iron in right heat was a problem. Below is the bag without a zipper panel:

I sewed the zipper (and some velcro for a zipper-protecting flap) to right panel and welded it to bag. Now, I had almost frame bag ready, but the cast was inside. Thus the first durability test was to rip the cast in pieces and remove it from the zipper hole. All went well:

At this point I noted that all seams were not thick enough, so I laminated some more plastic to critical places. After this I made some slits for straps and small holes to bottom, as I chose to use the bottle cage bolt holes as attachment points. Then I put the parts together and attached the bag to my bike:

The bag looked like it was made from a hide of a cancerous, Unclean beast. When I mentioned it in a social media, a friend misread "tein sen pedon nahasta" (I made it from a hide of a beast) as "tein sen pedon mahasta (I made it from a belly of a beast) so I promptly christened my creation to Pedon maha (which means belly of a/the beast in english). The bag worked well even when fully loaded (its volume is approximately 8,5 liters) but I felt it still lack something, so I made a small compartment to right side:

And as I had some gray and phlegm colored plastic, a P (cross) M decal (also laminated) in a mock death metal cd cover style. The cross should have been upside down, but it seems that the fumes from melting plastic have affected my brain:

The total cost of this frame bag came to be <10 euros (not counting the time used which was probably almost as many hours).

Bottom line: think of the dolphins (or your children, or yourself)! Don't throw plastic bags away, laminate them.