"Ahhh 'Grasshopper - bag makahhh' there are many weapons at our disposal in our eternal fight against the evil 'bag floppinesssss...'" Anyone who isn't a child of the 70's and didn't watch Kung Fu starring David Carradine et al. will think I'm bonkers, then again even if you are a child of the 70's you could still think...ah well, never mind...
To figure out how we are going to strengthen our bags, we first have to decide what function/s we want the bag to perform (i.e. is the bag going to hold fragile stuff like a lap top, or are you making a stiff clutch purse?), or what features we the want the bag to posses (i.e. do we want the bag to stand up on it's own, or do we want a padded bag, or do we want a sort rigid-ish sort of bag).
What happens if we don't reinforce our bags?
- You'll get a flimsy bag.
- Your bag weakens prematurely with normal wear and tear.
- Things won't stand up like they should (for some bags this won't matter, but for other bags, well, if you don't lay down foundations before building your house...you'll end up with a house on your head!
Figuring out and describing how to strengthen each and every bag would have me sat writing this post until I'm a little old bag maker! So, to make things a little easier in explaining how bag strengthening product can make our bag making lives easier, I'll recommend strengthening techniques and products for made bags and purses I've made. Does that make sense? Gibber Gibber!
Firstly, a look at some bag reinforcing products...
Interfacing & Interlining (also known as stabilizer). I've already written a pretty heavy duty (and useful, I hope!) post on this stuff because it's one of the BEST things to for strengthening bags and purses.
Polyester Boning is super useful in bag making... Sew this stuff into the seam allowance of your bag sides, or bag openings to prevent them from falling in on themselves. I use this stuff when I made this messenger style bag for my sister's Xmas Pressie. She said that it drives her insane when the main compartment of her bag flops in on itself. So I sewed this stuff into the sides and top seams to form a sort of flexi - skeleton within the bag to give the bag a boxy structure...
**UPDATE** Here is a pic (as requested) of me sewing some Poly boning through both layers of the top edge seam allowance of a wristlet. I usually sew with a 1cm allowance, so for me there's not much room for messin' about! If you are going to use poly boning in your bags, you can make life easier for yourself by sewing with a 1.5cm (1/2") seam allowance. You can either sew the boning into one seam allowance layer, or right through both layers, or even one piece of boning on each layer of your seam allowance.
Bag Bottoms are essential for flat bottomed bags. It honestly isn't worth saving money by using cardboard because NO MATTER how thick the cardboard is at the beginning of it's life as a bag bottom, it will end bending, breaking, or perhaps getting wet through normal wear and tear - and there goes your hard work down the toilet! Ideally, your bag bottom will be a little flexible (because that makes it so much easier to work with when making the bag), water proof, and break resistant (for obvious reasons).
Types of bags, and the ways in which I reinforced them:
- Embroidered silk tote made from heavy-ish silk with dupion silk lining: Silk needs to be reinforced if it's going to stand up the rigors to being used as a bag. I used med weight fusible interfacing on the exterior silk, then I used double-sided fleece on the interfaced silk on one side and muslin (or a fine weight cotton would also work) on the other side. I left the dupion silk lining as it was.
- Messenger bag made from furnishing weight velvet and quilt weight cotton and quilt weight cotton lining. I inserted a Bag Bottom on the (err) bottom of the bag in between the lining and the exterior. I also stitched poly boning into the four side seams and the front and back top edge of the bag. I used firm fusible interfacing on the exterior flap and gusset, then I used heavy sew-in in between the exterior and the lining on the flap. I left the lining as it was.
- Pleated largish bag made from furnishing weight fabric and quilt weight cotton lining: I used heavy sew-in in between the exterior and the lining to make the bag feel soft and slightly padded. I used firm fusible interfacing on the quilt weight cotton inserts. I left the lining as it was.
- Semi rigid clutch with shoulder straps made from quilt weight cotton exterior and cotton lining: I wanted this bag to have a firm boxy finish (that you could almost make a 'tapping' sound on). I used firm fusible interfacing on the exterior cotton, then I combined the interfaced cotton with heavy sew-in, and on top of that I also used craft weight sew-in. Craft weight sew-in is great for giving bag structure and making bags stand up on their own. I left the lining as it was.