Wednesday, August 30, 2017

Yet another modification to the slider

One of the aspects of my airplane that I have always been unhappy with was how poorly the canopy slid fore and aft.  The canopy itself fits very nicely but has enough flex and play that it moves side to side and the wheels tend to rub on the sides making a scraping sound.  The wheels don't turn easily and they tend to "rattle" as the wheels jiggle on the bolts that hold them in place when the engine is at idle.

So, I decided to do another little modification to the canopy.  I put new wheels on....but this time the wheels have real bearings in them!  I also used wheels with tapered edges on them.  The idea here is that at some point I can put a track in that holds the wheels fixed in the middle of the track so they don't rub at all.

After doing the bearing mod I found that the canopy slides much more easily.  Once I get the whole machining process down I may actually work on a new slide that has the grooves necessary to track the wheels.

Just as a reference if anybody wants to duplicate this mod here are the parts I used.

1. Wheels - I used the wheels from my CNC kit manufacturer.  (  I did have to put them on my lathe and turn the diameter down to the correct size and I didn't use any of the bearings included in the kit.  I did get the idea for using bearings from this kit though.

2. Bearings - I ordered these bearings with the idea I would put two per wheel in similar to the way my CNC machine works.  However I found that if I put in two bearings the bolts would stick out too far and rub on the inside of the track.  So I mixed up a bit of epoxy and glued a single bearing at just the right depth to hide the head of the 1/4" bolt holding the wheel on.

3. Spacers.  I used a lathe to turn the spacers you see in the picture below but I could just as easily have purchased a piece of aluminum tubing with 1/4" ID and 1/2" OD to do the same thing.

Anyway that's it and I am really happy with how the whole thing turned out.

Here you can see the new wheels with the bearings.  I have the SuperTracks slider mod on the airplane which is why I have two sets of wheels on each side.  This is looking from the outside of the cockpit back at the canopy slid all the way back.

A little better veiw of the mount. You can see the taper in the wheels with this picture.

While I had this all apart I decided to modify the inlet to the SuperTracks rails to be a little less "sharp".  I found that I jabbed my shoulder with the original design and this just seems to work much better...and it looks better.

Outside view of the SuperTrack rail mod.