I have heard them refered to as clevis pins, I used them on my yak cart that I built from the CLC plans. This looks like a more compact design. Did you get the pins with multiple holes down the length? I got those and two of the clips per pin. That way I can clip the clevis pin into the cart and then put the wheel on the pin and put the 2nd clip through the pin to hold the wheel on. (there is a clip on either side of the wheel going through the pin) This allows me to take the wheels off for storage of the cart in a hatch without the pins falling out and getting lost. You may not need this feature if your cart with wheels on will fit in your hatch

Look forward to seeing the finished project.
Mike

I went into this side project because of some annoying (but unavoidable)
: delays in deck stripping. Anyway I've got the wheels/pins and form ready
: to go. 3/16" strips of WRC (core) and Black Walnut (shell) are
: soaking in this makeshift PVC trough. I'll let them soak 24hrs and then
: fire up the (PVC) steamer if I have to.

: So the cart chassis will be two "U" shaped laminations that nest
: together when folded and open out into a "V" when it's time to
: roll. I copied this design from numerous posts, commercial models... looks
: like it's one of the more popular designs. I picked up the axle hardware
: at Lowes. I can't remember the name of those pins (bottom foreground of
: picture). It seems like Lowes has the best selection for loose hardware
: like this.