Sat Jan 24 2009

Wheel nut modifications

Today I broke out the instructions for modifying the wheel nuts for the new Avery jack. Here are the wheel nuts from Van's along with the new brackets, screws, washers, and instructions from Avery.

First thing to do was to drill out the platenuts. Interestingly, one of these platenuts is crimped in two places while the other one is crimped in three places. Odd.

At this time I decided to work on the "washers" that are used as backing for the plastic glides which the seat belt shoulder harness cables run through. I hacked some .040 into (roughly) squares per the plans. However I didn't like the idea of using squares here. I thought it would be hard to keep them aligned so I decided to make round washers instead.

First step in this process was to stack up all the little squares and then bolt them together using a 1/8 inch screw, nut, and a couple washers. How did I happen to have such a screw / nut combo available?

...over the years I've followed my dad's practice of collecting hardware odds-n-ends in a jar. I just sorted through some of this junk and found what I needed.

Once it the screw and nut were tight I chucked the free end of the screw in the drill.

After some time holding the rotating stack against the disc sander, then the scotchbrite wheel, I had a nice round stack.

Unscrew the stack and presto! Eight nicely uniform aluminum washers.

After doing that, I went into work to use one of the milling machines to modify the wheel nuts per the instructions. I milled a notch 3/4 inch wide and .050 deep in the end of each nut. I also bored a 1 inch diameter hole through the end. Since I already had the mill setup, I used a center finder to locate the hole in the center of the brackets and drilled a #40 hole 9/32 to each side of the center hole.

I clamped the bracket to the nut and used my hinge bit to drill a pilot hole for the #10 screw.

The hinge bit did a good job of getting the pilot hole perfectly centered on the bracket clearance hole.

Last thing for the evening was to drill these holes to #21. I don't have a 10-32 tap, so I'll have to run out to the hardware store tomorrow before I can tap these holes.