Ole South

Why not cut brass tubing (you can get really small diameter stuff at the Hobby Lobby type shops) and use your snap setter to flare the ends. I know this is really old school but... Btw, brass holds tighter than aluminum for me in this type of situation,

Re: Edge Guide/Seaming Guide for the straight stitch machines. I use a hardwood block (closed grain, unvarnished) of maple or such and a rare earth magnet or two salvaged from an old hard drive set flush into the bottom. A thin piece of soft tacky self-stick vinyl (a friend is a sign maker) keeps the diy guide from drifting. It's not really necessary with the approx 1 1/4 x 1/2 inch magnets from the average 3.5" computer hard drive (you'll find 2 in there) but the vinyl also protects the machine's finish if you're worried about things like that. There are also threaded holes in most old Singers for a slotted "T" guide you can secure with a thumb screw like an inverted router guide. I've not used one yet but you can find them amongst the misc. accessories on Ebay or in your local Singer repair guy's junkbox. I stole the magnetic block idea from a Sailrite video. Cost = about 20 min cutting the magnet's inset (ie.$0.00 vs the $25.00 5 1/2" Sailrite Mag Guide). Make sure you use one or more ceramic or rare earth magnets to get the holding power you'll need. It's a cheap and effective way to guide those long straps and edges on a fixed presser foot machine. (Round or taper the end of the guide for any inside curves you may have to sew)

Skive the gusset overlap and corners. Check out Nigel Armitage's " Make your own messenger bag" on youtube. About minute 7:49