There's a design issue with these prewar bikes that I've been thinking about how to address. The "wire" stays that hold the mudguards were stamped in a press that formed them into the U shape and formed a hole for the mounting hardware. This stamped hole has extremely small amounts of metal at the apex of the hole. The hole itself concentrates the stresses from the long wire arms right to this thin metal area. Needless to say, I can imagine I'm not the only one with some of the wire stays broken in half. I broke one myself while cleaning the red paint off this stay.
From what I see in the pics of bikes from the later 40's, the Schwinn designers addressed this by moving to a bent piece of flat metal instead of forming them from a round "wire". I'm sure they are still not super robust in this new form but it's better than what you see above.
Gramps had mummified one set of stays with stainless steel wire to hold them together with a washer and nut arrangement. Pretty whacko but it worked for decades. One of the stays is still in one piece, but when I look carefully at it. I can see that it was brazed right at the hole at some point. So it was broken too, years ago.
I wanted to make something a little more slick using the 3D printer. I took some measurements with calipers and put together a drawing of what I was thinking about.
Worked on it in CAD for a spell and got it to look like I was hoping. I iterated a couple of times to get a nice fitting part with a pocket for a captive nylock nut.
Converted it to a file for the 3D printer and printed them out.
Here's a look at some of the iterating I did to get it dialed in.
I'm pretty psyched with how well they fit and hold all the loose parts together.
Bought enough stainless hardware at ACE today to equip all 3 stays. Spray painted the stainless Nylock nuts flat black to hide the mount a little more. Tried to keep the paint out of the threads when I was spraying them.
Installed they look pretty low key and work great.