The last time I got new cheques, they where attached along the top rather than the left side like all the other cheques I ever had. Needless to say, the fancy leather chequebook cover I made no longer worked. So I made this one.
This is the second simplest duct tape project of all time (see the bookmark for the simplest). It is also good practice for making duct tape sheets. My chequebook required about 3 1/2 yards of duct tape and took about 20 minutes to make. YMMV.
My new chequebook is about 6 1/8" by 3". The cover is one sheet with two 3" pockets with a 1 1/2" gap between them. So my final sheet is 6 1/2" wide by 3" + 3" + 1 1/2" + 3" + 3" = 13 1/2". Adjust the size to fit your cheques.
Now take the sheet, fold over the pockets and tape the sides. Fold in half and you are done! Now you can write out a cheque for more duct tape.
If you have the old style cheques that are bound on the left, I would try making the same size sheet. I would then put some reinforcing tape along the left side of the bottom pocket. A piece on each side of the pocket would probably be enough. Then cut a slit through the tape about an 1/8" or more from the left edge. Then tape up the sides and the top of the bottom pocket.
Disclaimer: I have not tried this. If you make one and it causes your cheques to burst into flames, it is your problem.
It seems that the good folks from south of the border in the U.S.A. call cheques checks.