R100GS: Custom Polycarbonate Screen

The stocker just threw turbulence at my head when it was 'up', and hit the raised bars when it was 'down'. With a bit of judicious filing, I modified it so it could go 'up' slightly further, but that made the turbulence worse. So, rather than cut down the stocker, i decided to make a new one from scratch.


          |---200--|                  |     All dimensions very
        |----290-----|                |     approximate and in mm.
         ____________        ____     |
        /            \                |     Bend along the | lines so
       /|            |\      155      |     that the . holes line up 
      /.| __________ |.\     ____     |     with the screen mounting
     / .|/          \|. \     45      |     posts with the front of 
     ~~~~            ~~~~    ~~~~     |     the screen slightly bent.
       |------370-----|               |    
     |-------450--------|             |     
Sorry about the ASCII art. Mounting holes are 13mm, with grommets to fit over the 10mm posts on the fairing, and flat bits of aluminium to hold it all in place. I'll get around to painting those so they look a bit less lame.

UPDATE: I rotated the bars forward a bit, which feels much nicer on the wrists, but I had to file in a notch for the brake light switch. The screen now has a nice coating of bug guts, too, so my lousy bending is a lot less obvious ... but, also, the the polycarb has cracked at the edge of one of the upper holes, where I drilled it too close to the edge. It's small enough that you never really look through it anyway.

The stocker is about 295mm high in the middle, so this screen is very almost only half the height ... I'll get around to making a 'real' one if I decide to keep the fairing.


(it's about 185mm high in the middle in these photos, I trimmed it down a bit after the Trout Rally)

Working with Polycarbonate

I cut it with a coarse hacksaw blade in one of those hobby hacksaw things, where the blade sticks out past the end. Kind of a hand-powered jigsaw. Worked okay. I cleaned up the edges, rounded off the corners and cut out the internal angles with a strange tool which looks a lot like a cylindrical wood rasp, in the drill press raising the drill presses platform until the bit went down through the center hole, and sliding the work into it. Worked very well. Covered the shed in plastic snow.

Drilled the holes with a 13mm spade bit rather than grinding down a twist drill ... that worked well too.

Bent with a hot air gun, clamping the middle part of the screen down to a workbench and bending the sides with a sheet-metal working tool. Very hard to get the whole bend to soften at the same time. Also, I didn't dry the polycarb out, which caused it to bubble up in a couple of small patches. Need a small oven for the shed!

There's lots of stuff on the Web about polycarbonate.

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