Ersatz 5.5 mm Nut Driver

A tiny 1/4 inch hex driver handle appeared from the far reaches of a drawer, sporting a handle better suited for tweaking the 3 mm adjusting nuts on the bottom of the M2’s platform than applying actual torque to real fasteners. Rather than breaking a set of nut drivers, I made a simple brass shim to soak up the difference between the handle’s 6.5 mm ID hex and the 5.5 mm OD of the nuts:

Hex driver shim - installed

Hex driver shim – installed

That’s 15 mil = 0.40 mm shimstock to leave enough clearance for my crude forming technique.

Which technique consisted of making a “mandrel” by lining up a trio of Nyloc nuts on a screw, snipping off a suitable shimstock rectangle, and squashing it into shape with parallel-jaw pliers:

Hex driver shim - forming

Hex driver shim – forming

As you’d expect, the shimstock hex came out larger & uglier than the mandrel:

Hex driver shim - formed

Hex driver shim – formed

But that doesn’t matter after it’s tucked inside the driver; it works perfectly.

Took less time to do than to write up …



  1. #1 by steve on 2016-06-30 - 09:18

    I did something similar when I needed a 36 mm socket and all I had was a 1.5″ one…

    • #2 by Ed on 2016-06-30 - 11:04

      It’s one of the very very few times you can (easily) make a hole smaller …