I finally make something that isn’t 3D printed.
Call me old fashioned, but I don’t use my phone for everything (yet). I always like to keep some cash, credit cards, and ID on my person.
Ridge wallets intrigued me - two metal plates connected by an elastic band, holding your cards and cash in compression. I bought one, but something about it felt… cheap. Probably a combination of its light weight, elastic bands, exposed insides, and less-than-subtle branding.
So I decided to make my own. But classy.
“The customer is always right in matters of taste.”
I wanted to change three things:
-
Hide the cards and cash
-
No elastic band
-
Add some heft
Design:
My original concept was a slim box with a leaf spring inside. However, I found that by folding bills in a particular way, the cash itself could act like a spring. I call it a “cash-jam” mechanism.
Okay, I lied. There is some plastic prototyping in this project.
Two plates bolt onto a U-shaped fork in the middle. I kept the aspect ratio of a credit card. Capacity ranges from 1 to 6 cards depending on how much cash you carry.
The front plate has a large relief for your thumb, with a smaller one on the back for your index finger. It has a nautilus shell shape so that you can pivot with your thumb in a sweeping motion (right-hand operation only).
You pinch and slide the top card to remove it. To retrieve cash, pull all the cards halfway, which drags the bills up for access.
Cards can be inserted from the front or back to reorder them. After spending cash, you fold the bottom of remaining bills to provide more jamming force.
(Thunk-thunk) ONE-HANDED INCREASED TO 69
Materials:
The plates are made of carbon fiber (2x2 twill weave). Not only does it look nice, but the resin is also very scratch resistant. Two years later and they still look brand new (despite sharing a pocket with my keys).
The middle forks could have been made from a wide range of materials. I was taking a CNC machining class at the time, so I had brass on the brain.
Manufacturing:
I intended to machine this during class, but didn’t finalize the design in time. So I paid PCBway to make it. They did a great job and the price was reasonable for such an oddly shaped part.
The carbon fiber plates were waterjet cut by SendCutSend (10/10 service, would recommend).
The only features I didn’t contract out were the countersunk holes in the carbon fiber plates (not a service SendCutSend provides in this case, and for good reason). Cutting carbon fiber releases tiny needle-like particles that are dangerous to breathe and like to bury themselves in squishy tissue. No wallet is worth getting expensive asbestos in your lungs.
Using some linear rod and an old drill, I made a pecking tool loaded with an abrasive cone. The bottom gets submerged in a Tupperware filled with water to capture the dust. Problem solved!
“Carbon fiber smoke! Don’t breathe this!”
Finishing:
I polished the brass to a mirror shine. However, it collects fingerprints fast. I later took it down to a more matte finish.
Money shot. Pun intended.
This is definitely one of the nicest things I own, and I use it every day. The carbon fiber weave changes in character depending on how the light hits the surface, and it feels nice in the hand.
Using it was finnicky at first, but I like how this wallet turned out.
Now back to 3D printing!