Monday, November 19, 2018

Shredder Tensioner, Chute & Flywheel Musings



The previous chute wasn't working for me. I decided to disassemble it for the license plates and start anew. I started with a big sheet of reused foam core and ended up with a two-section chute meant to take the plastic flakes away from my left foot as I pedal, then deposit them into a 5-gallon bucket.

Time to try it out for real. The original chute was held on by a magnet and a bungee. While it seemed secure enough at first, I kept running into issues with it falling off. I decided to make a slightly more secure solution, shoving the far side into a piece of C-channel aluminum and integrating the near side with the shredder's removable pins. Full explanation in the video below:


You can see that the chute clears the pedal quite well, and dumps the flakes almost vertically into the bucket. It could probably stick out further, but then I'd run into storage issues. It's probably going to be alright.




Of course, to get that C-channel in I opted to remove the shredder for easy access. While it was off I gave the raw steel pieces a quick spray of black paint.


You may notice the new chain tensioner up top. I'm converting over to derailleur idlers instead of the plastic bushings. Photo from last night. It may need additional adjustment in the future, but for now I'll see what happens.


 Back to the chute...


I deemed it worthy. Then I bent up a couple license plates for sides and cut down some polypropylene Sterilite lids for bottoms.


I found that these PP sheets are easiest to cut by scoring a straight line then bending the sheet until it snaps. Less trouble than cutting all the way through or using the table saw.

I had to buy a new pop rivet tool because my 'vintage' one clogs itself on just about every other rivet. The new one works great and things started to go together quickly.

The grey plastic there was bent in a vice. I lightly heated the bend area with a torch and pushed it over with a wide board, just like a rudimentary sheet brake. With the right amount of heating, the plastic sheets hold their shape well. It didn't smell but I would NOT do that without outdoor ventilation.


After lots of hours of work, I devised a secure mounting system out of metal scraps and had over half a chute finished. I'll be sure to update with a video when I get it done (hopefully tomorrow). As it is, though, the new chute appears promising, and is made from 100% trash materials (aside from the rivets)!

Last, I did lose a little sleep over the flywheel problem and came up with a potential solution. When I got this Schwinn exercise bike for free I was told to also take another one- the owner wanted to get rid of it. I scavenged a few parts and recycled most of it. One part I kept was its flywheel, which happens to weigh in at about 20 pounds (9 kg). That's almost twice the weight of the Schwinn wheel!


The bike shop is closed starting tomorrow for Thanksgiving, but I'll be taking this wheel in next week to see if we can make the 5 speed freewheel fit. If so, this will give me an instant doubling of flywheel weight, if not energy storage. I plan to have a fab shop add some weights inside the thinner area to get the thing up to 30 or 40 pounds. That's the simplest flywheel solution I can come up with.

No comments:

Post a Comment