There are quite a few pattern pieces to this: the front/back, sides and bottom, top, zipper pull, tabs, plastic pockets on the inside with bias bindings, plus the bias binding around the outer edges. The layers include the fabric, backing, batting, and plastic.
The original size is 2 1/2" x 12 1/4" x 9 1/2", a good sized one. However, I found that items fall to the bottom and give it a fat look, so I decided to make it smaller but deeper. The dimensions to this one are 4 1/4" x 10 1/2" x 7. Because the height is less I also picked a 14" zipper instead of the original 16".
I have a few more items which need replacing, although none is as bad as the original large bag was.
It seems as if I want pieces to be like I want them to be, not like offered in the pattern. This involves some planning and sometimes a bit of math. The binding is stitched together at the ends so it is one long piece; therefore, it must be the correct size before stitching it onto the bag.
Instead of doing a lot of math, here is an easier way to determine how long to cut it:
--take the original perimeter of the bag as given in the pattern, in this case 2 x 12 1/4"= 24 1/2" added to 2 x 9 1/2" = 19" and add together for 43 1/2".
--take the desired perimeter of the new bag, in this case 2 x 10 1/2" = 21" added to 2 x 7" = 14", and add together for 35".
--subtract the new amount (35") from the original pattern (43 1/2") for 8 1/2". Fold out the pattern for the binding this amount.
This is a lot easier than measuring the perimeter of the new size. In this case, probably either way would work, but for other types of patterns, they may have added an ease amount which could throw off the calculations.
So, that's another item I have completed. In some of your e-mails you have asked where my knitting and crocheting is (other than the doll clothes). Yeah, um, well......
Adding: I meant to make the math less confusing not more so! OK, to put it more simply, instead of having to measure the altered perimeter to determine what length to make the outside binding, measure the original and the new one, and substract the difference (or add it, if making larger) and substract (or add) that difference in the binding pattern piece. Hope this is easier!
Another way to look at it is if I make a skirt waist 2" larger, I would just make the waistband 2" larger also. This would be easier than measuring the new skirt waist, then deciding how much to make the band (because I might not include the amount to be eased into the waistband.)
I did paragraph in the second half of my original post, so why it didn't come out that way I don't know. Maybe I should do more reading in the Help area here! OK, I've edited again--hope it has worked this time.