217
edits
Projects/Scooter Roof: Difference between revisions
From London Hackspace Wiki
→Windscreen
| Line 79: | Line 79: | ||
* Material | * Material | ||
The main choice here is either to use glass, persepex or polycarbonate. While glass provides excellent scratch resistance it is very difficult to form in a one-off situation, it would be very heavy, and a laminated screen would be essential for safety reasons. The choice then comes down either to Perspex or Polycarbonate. | The main choice here is either to use glass, persepex or polycarbonate. While glass provides excellent scratch resistance it is very difficult to form in a one-off situation, it would be very heavy, and a laminated screen would be essential for safety reasons. The choice then comes down either to Perspex or Polycarbonate. Polycarbonate have many advantages over glass and perspex alternatives. | ||
Polycarbonate is much lighter than glass | |||
Polycarbonate is shatter resistant, unlike perspex, glass and other acrylic derivatives. | |||
Polycarbonate is 250x stronger than glass and considerably stronger than Perspex | |||
However, Polycarbonate has very low scratch resistance unless it is coated with a scratch resistant covering | |||
I again had | Scratch resistance is a big consideration given that I wanted to use a windscreen wiper on my screen. My Benelli Adiva has a plastic windscreen | ||
I again had my decision made for me in that I was able to acquire a second-hand comfort windscreen in good condition at a very low cost. I based my design on the use of that windscreen, although the scratch resistance of this windscreen has yet to be determined. | |||
===Windscreen wiper=== | |||
The decision here was fairly easy as I already have experienced parallelogram windscreen wipers, so I was happy to obtain a second-hand wiper motor and arms from a scrapped bike. A custom set of mounting brackets were needed to mount the wiper. | |||
==The Build== | |||
===Manufacturing the frame=== | |||
I had chosen relatively thick walled aluminium tubing to make it easier to weld the joints without blowing through the tube ends. The downside to thick walled tubing was that I found it cracked if I bent it at two tight an angle on our pneumatic pipe bender. I tried to anneal the pipe before bending to see if I could reduce the cracking issue but found that it didn't make much difference, since I've never tried this process before it may have been that I needed to experiment further with heating and cooling, but I found that I could just about get away with bending the tubing as much as I needed to form the frame without cracking the tubing. | |||
All the coping joints were made by hand with an angle grinder which produced acceptable results and then TIG welded. | |||
The frame is designed to be easily removable from the bike if it is not required for use in the summer. Two 8mm stainless steel bolts hold the frame to the subframe, which is held to the front by four 6mm stainless steel studs, and at the back to an aluminium subframe made of l-shaped extrusion bolted with more 6mm stainless steel studs and nyloc stainless steel bolts. | |||
The windsreen is held onto the frame with 6mm stainless steel bolts, which fasten into threaded holes. | |||
===The windscreen wiper motor=== | |||
The windscreen wiper motor proved | |||
Mounts for the windscreen and windscreen wiper were then welded on. | |||
