Outer Hub Step Removal Tool

by Stan Pope, Morton, IL
a Volunteer Scouter for W. D. Boyce Council, BSA, Peoria, IL

Introduction

Some of us are allowed to work the hub faces, such as removing the step on the outer hub of 2009 BSA wheels.



I selected a well worn 15/64" 2-flute drill bit from my bin. I'd have selected a 1/4" bit, but it did not fit the recess in some of my wheels. (Wouldn't want to get someone DQ'ed because they worked too much of the face.



On the grinder, I ground down the tip until the drill face was flat ... rather like an end mill. Then working each of the flutes separately, I ground a slight angle so that only the leading edge could contact the workpiece.



Next job was to prepare a stop. On my lathe, I cut a cylinder about 3/4" long and between 1/2 and 5/8" in diameter. Next, I drilled a 15/64" hole down the axis and polished the surfaces with 320 grit emery paper to minimize defacing the wheel.

Lastly, I drilled a small radial hole (#25 drill bit) near one end and tapped it (#10-24 tpi) for a set screw.



Finally, I set the caliper to 0.040" and used it to guide the stop as the set screw was tightened to lock the stop to the drill bit. This took too many hands, so grandson Andrew held the caliper in place and tightened the set screw with an allen wrench while I held the bit and stop against the caliper.



Drill Press Setup

Workpiece locator: In a small piece of wood, drill to depth 0.1" with size matching the wheel's inner hub diameter.

Chuck the Step Mill in the drill press and attach a clamp to the drill press table so that it can clamp about 1" from the Step Mill.

Place a wheel in the Workpiece Locator, align the hub face of the wheel against the end of the Step Mill, and lower the assembly to the drill press table, sliding the locator under the clamp and holding it in place as the clamp is tightened.

Launch video: Drill Press Setup

Step Mill Usage

  1. Place a wheel in the Workpiece Locator. Hold the wheel in place through the next steps.
  2. Turn on the drill press.
  3. Feed the Step Mill into the wheel's hub face, reversing quickly when the stop touches the spoke face of the wheel.
  4. Visually check that the step was removed.
  5. Turn off the drill press.
  6. Extract the finished wheel from the Locator.

Launch video: Operation

Launch video: Measure Result

Safety Note. The corners of the Step Mill are sharper than for a normal bit. (Not as sharp as on a brad point drill bit, though.) Use care when moving around near the Step Mill even when the drill press is off! To help avoid snagging one's fingers on the sharp edge, I suggest that the retracted drill press spindle lift the Step Mill about 2 inches above the wheel.


Original: 1/6/2012
Update: 1/7/2012 - Add Videos

Copyright © 2012 by Stan Pope. All rights reserved.