DIY Home Engineer

My wife’s nice Targus roll bag that she uses walking into work had cheap roller wheels.  These wheels were sort of a vinyl covered foam that wore out quickly.  She does walk on downtown sidewalks a couple of blocks from her parking garage to her office so it isn’t light usage, but still those wheels wore out quickly.

I’ve had good luck using inline skate wheels on my home office desk chair and felt that type of wheel would be much sturdier.  I measured the wheels that were on there.  Digital calipers were nice but it wasn’t exactly a precision measurement.  I got 62 x 28 mm for the wheels.

Searching on Amazon I found a number of different sets in that size, both for skates and for luggage.   I didn’t order any axle sets because I wasn’t sure how long it would need to be.  I felt my local Menards would have those.

The first try for taking the wheel off was to grind a slot into the end and see if a screwdriver could unwind the axle.  While I felt this was a low probability of working it wasn’t going to cost me anything to try. This is where I got my first really good look at the construction.  It looks like the wheel-axle combination was swaged onto the plastic corner of the case and THEN the corner was riveted onto the case.  That meant that I didn’t have very good access to the inside part of the axle.  I was worried that the fix would require cutting off the rivets, removing the hard plastic corner and then re-riveting.

Fortunately, I was able to dig down on the interior of the case and see the edge of the wheel-well from the inside.  This made me comfortable that a nylon-insert nut could be threaded on from that perspective and I wouldn’t need to remove the shell.

The documentation on the wheel mentioned a 6mm shaft and if the bushing was removed an 8 mm interior bearing surface.  I found that a 1/4 thread fit it easily with no slop.  I measured 1-1/2 inch from where the test bolt emerged from the wheel-well to the outside surface of the case. That meant I needed another 1/4 inch for the nut.  Of course they didn’t have any 1-3/4 length at the store so I ended up with 2-inch bolts which probably worked just as well.

At first I tried seeing if I could cut the shaft with my oscillating tool.  I didn’t really have a clear access to the shaft. I could tell I wasn’t getting anywhere near the shaft because of bushings in the way.  The bushings rotated with my tool so the hacksaw approach just wasn’t there. I ended up using the oscillating tool on the wheel itself and once I got the plastic of the tire removed I saw that the entire span between the supports was bushing.  All I ended up doing while trying to cut was generating heat.

Plan B was to cut the end off of the wheel axle.  I ended up doing this fairly slowly since I was trying not to cut into the plastic supporting the axle and I wanted to give things some time to cool.  Melting the support plastic was not in the plans.  Once the end was cut off it was fairly simple to use a #1 Phillips screwdriver to drive the axle out the other side.  Scorecard:  1 axle fell out externally, one internally to the case.

Now it was simply a matter of putting the bolt through the supports and wheel and threading a nylon-insert lock nut on the inside.  I’m not sure what value that is for simple.  It was pretty much the hardest thing I did.  Working in a confined space with light that didn’t want to cooperate and a nut that had to be pressed really hard into the corner to have clearance to line up the threads.  Once I got the nut threaded I ran into issues getting enough torque to thread the nut instead of just spinning it.  There wasn’t room for any adjustable tools so I got out an actual 9/16 inch open-end wrench and hand tightened the set.  Easy but hard.

Scorecard

Materials were easily available, most of the tools required were pretty common except a Dremel type rotary tool with a cutoff wheel.  The repair required a surprising amount of patience and perseverance but that was largely dependent on this case.  The concept was certainly simple enough.