For quick repairs i have used coloured duck tape, you can even get clear for windows etc.. and sticks great. I have also used canvas patches as suggested above and all is fine - dont worry too much about the waterproofing as this should be fine once you have done any of the above - if still doubtful then you could always spray it with fabisil
Put a small "Wales" badge ove a hole in my previous TT. It looked like it was supposed to be there as it was near the door. Stuck it on with copydex and hand sewed around it.
------------- Steve
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I like the odd drink. Five is odd, seven is odd, nine is odd...........
dont ever sew your canvas as you just put more tiny holes into the canvas than the large one your trying to fix!!! copydex and a bit of your peg bag, which is usually the same colour as your main canvas is all you need to repair