Bicycle Power!February 12, 2009 at 11:40 am | Posted in Uncategorized | Leave a comment
Anna here….exiled from the farm, adrift in the big city, wide-eyed at UWS fashion and driven to exaperation in the canned tomato aisle — organic? no preservatives from italy? what am I supposed to eat????
But….the nice thing about having the winter off is that I have time to do projects. I learned how to knit lace patters (this scarf is pretty easy, and lots of fun). And my latest project has been converting our Country Living Grain Mill to be powered by an old exercise bicycle. It’s been a frustrating, humbling, and ultimately hella-exciting project! Check it out:
(x-posed from jcarrot.org)
I did it! And it only took two weeks, four trips to the hardware store, five different configurations, one temper tantrum, two phone calls to my carpenter-savvy father, three trips to my local bike shop (LBS) and looking at the photos of other exercise bike grain mills online about three hundred times.
Things that excited me about the process:
1. Everyone’s excitement, including the posts from the bike folks in Portland. Just generally feeling good and supported at the knowledge that there are folks out there who find this stuff cool, and, even more so, important.
2. Getting a little more comfortable with power tools, and learning about some new hardware. Locking washers have a little cut in them, and they will prevent your bolts from rattling off because they are in tension when tightened. Plywood is harder than regular boards, and a hole drilled in plywood will be perfectly smooth, but it will smell bad while drilling (chemicals?). Home Depot has a scrap wood cart that provided most of the wood for very cheap.
3. The fact that I can now get some exercise (it’s still takes a fair bit of force to get the thing going, it’s no weekend pedal in the park) and mill grain into fresh flour at the same time!
Some of the challenges I had to deal with:
1. Resistance. I ended up changing the rear sprocket to a smaller one, so that the ratio of front to back would be smaller (easier to pedal). Good thing too, because the inside of the crank shaft was all rusty and probably couldn’t have taken the kind of exertion it’s going to get in this set up. Now it’s all freshly greased and ready to go. If you’re considering a similar project and using an old bike, this is definitely something to pay attention to.
2. How to get the multi-cog onto the flywheel. Originally I bolted it to a piece of wood, and then bolted that piece of wood to another one on the other side of the flywheel, sandwiching the flywheel in the middle. This worked, but it put the actual cogs about 2″ out from the actual shaft on the mill. With so much pressure being exerted, it was twisting the whole mill from its base. I corrected this by fastening the multi-cog directly on the flywheel, and using the biggest cog (closest to the flywheel as possible). so now the chain is pulling maybe 1/4″ further out than the main shaft. Still not perfect — the best thing to do would be to get the cogs right on the shaft as Maureen Ash did — but I don’t know how to do that (Her full story is here). Hopefully this way will work for now.
3. How to secure the mill in exactly the right spot. I ended up bolting two 2x4s to the bottom of the frame. I attached the grain mill to a 3/4″ piece of plywood (from the scrap bin!). That way I can position the board with the mill exactly where it needs to be to have the chain line up, and then fasten it down with C-bolts (3″x4 1/2″). The way I positioned it, the mill is bolted to the board off-center, so that the bolts on the bottom can hang free, and the board can be bolted flush to the 2x4s.
4. Breaking a chain. Don’t push the pins all the way out — they don’t go back in!
If you’re interested in doing this, please feel free to contact me for more info on how I did it. I am by no means an expert — the list below explains some of the challenges I ran into as I was going along…and didn’t know about before I started. Hopefully this information will be helpful!