Knitting a Bento Bag

This year, I thought I'd knit my sister a bag for her birthday.  In my stash, there were still a couple of hundred grams of Texere wool, aran weight, dyed two shades of greenish brown with larch bark a few winters ago.  This previously knitted up good and durable and I pondered on knitting it double with a colour change, dk weight single yarn in a silk/wool mix which I bought in an online sale.  Of course, the price was too good to

be true.  Heaven knows what was done to that silk before it got spun, but it has no shine and comes apart with the slightest tug. Fancied a slipped stitch pattern, which ought to spread the load of a bag between rows, allowing me to knit the weak yarn alone, but adapting a bag pattern to take account of slip stitch repeats 

would involve more knitting maths than I really fancied. Browsing about online, the Tolt Folded Bag looked a brilliant concept, based on the Japanese Bento Bag, which has a tied top.  Any piece of fabric or knitting which is three times as long as it is wide can be folded to make a curious and  

pleasingly shaped bag with the absolute minimum of seams. Hard to get my head around, so I made one with a piece of paper and when the origami worked, I made a hippy beach bag out of a big scarf which happened to be three times as long as it was wide.  The third fold is a diagonal down across the centre square left to right.  The big scarf made a huge bag, hanging off the shoulder to below the hip.

Three folds do interesting things to stripes.  I knitted Triple L Tweed slip stitch, casting on 49 stitches and knitting two shades of the aran and the colour change wool/silk blend in turn, til the length looked about right.  I left it live on the needle cord while I folded the bottom and crocheted the first seam, finding the

Triple L pattern made it easy to match the edges correctly and also, that I would need a few more rows than I thought to make the other side match.  Having cast off, I put a line of double crochet round the whole of the open top, to firm and even up the exposed selvedge to match the length of the cast on and cast off edges. 
I rather like the Bento shape.  My companion, Elinor Gotland, had her doubts.

"Funny looking bag, Beaut.  You won't tie handles in that thick knitting."
"What do you think I am, daft? The Tolt Folded Bag pattern has a knitted handle and I am going to crochet one for mine."
"Bit low in the middle though.  Your sister won't thank you when all her stuff falls out."
"Luckily, the 28cm starting row width made a 37 x 37cm bag that fits an A4 file rather neatly, which is just the sort of thing Pip needs to carry about.  See how well it hangs up on the back of the door."
Which I then shut, firmly and ran downstairs, whistling loudly.