Shoulder Nut 1/4 - 20

thingiverse

The fastener in question is a 1/4 - 20 Shoulder Nut and Spacer, used on our "Skate Wheel Conveyor". We redeployed this equipment from storage, only to find it missing one crucial odd fastener. Despite searching at local hardware stores, none were found. Grainger has been trying to source the part for weeks, but so far no luck. One supplier is willing to sell 50 of them, but that's not a viable option. The original spacer was made from Nylon or Delrin material. A shoulder nut functions like a barrel connector with inner threads, capped at one end with a wide shoulder washer and a hex head. The Skate Wheel Conveyor uses an "all-thread" threaded rod as its axle, supporting an array of wheels and spacers. One shoulder nut is used on each end to hold everything together. The problem arises when the threaded rod is flush with the hole in the support legs, preventing the use of a lock nut. The ABS material may not hold up for long, but we don't have the temperature control needed to produce Nylon successfully. We're considering trying carbon fiber PLA as an alternative.