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Tuesday, December 11, 2007

New Pics of two versions

Well, I keep saying I'll post pics, so here are a few. First up is the Plan A 1/2 (version 1.3.1 now), using my Columbia aluminum frame bike as the base, with the portion of the wrecked steel Schwinn Ranger attached to the back end, in reverse, at the rearwheel axle points.

This is the "overview" of the motor drivetrain, with the wheel chainring cassette at the left, the derailer (currently only being used as a tensioner--it can't work the way it's designed on the left side yet as a derailer, I must first rebuild it, or build one from scratch, in mirror image) in the middle, and the motor's chainrings on the right. Currently no motor is attached, but it would be on the other side, out of view.

Here we have a couple of shots of the wheel's new leftside chainring, which because I have no machine shop available to me, I had to just build from the raw chainrings JBWelded together in a stack (which was very hard to keep aligned, even with a vise, both before applying the JBWeld and during cure). I also had to JBWeld it to the spokes and hub for the testing stage, as there is no way to mount it on here with any tools or hardware I have available, until I can build a freewheeler that ratchets in reverse so it will work on the left side. Again, need a machine shop.

View from the front (forgot to rotate the image) and outside:

View from the rear and inside (again forgot to rotate the image):

This is the rear assembly from the motor's side; you can see the 7/8" drive socket bolted onto the former pedal crank mount--I simply ran the bolt thru the socket's drive hole and into the pedal crank mount as I would have to put the crank itself on. There's a washer I milled out with the Dremel inside the socket that forces the bolt to fit exactly in the center of the hole, as it was a bit smaller than the actual square drive hole in the socket, of course.

At the top of the image is the kitty litter pail I used for a cargo container, which has proven watertight during two trips in heavy rain this last week. The angled post sticking out the back isn't an exhaust, it's simply the support I'll use to put the cargo container on (vertically) when I move it off my cargo rack at some point, to help lower the bike's center of gravity and make it easier to balance and ride when loaded. It's possible I might end up with a pair of them on either side of that post instead of a single one on top of it, too, depending on how wide the rest of the bike ends up with battery trays and such. I don't want to put too much of a cargo load behind the rear axle, though, because it will take so much weight off the front of the bike I might lose traction turning, and skid out; at the very least it is going to put more strain on the rear tire (which is already hard to take off to repair/replace; another point I need to consider and fix, so it's just as easy as it started out to be).

Just below it is my taillight/brakelight, made from a Microtek scanner attachment light--I simply cut it's cord off and wired it into my controls at the handlebar, via diodes to the headlight switch and a switch on the rear brake handle. It will be on both brakes later, but just this for now, since I always use the rear brake, but cannot always use the front brake due to sometimes having to have my left hand off the bars for turn and stop signals.

Later on, I will have LED turn signals to replace the hand signals, once I have enough super-bright yellow and/or amber LED's for the purpose. I need them visible in daylight, so there need to be more than a few of them at each position. There will be rear- and front-facing ones, as well as some on each corner for visibility to the side and from angles. I already tried just wiring up some auto lamps, and they drained the battery in only a few minutes of use, thus are impractical. LED's are the only low-current high-brightness option I really have.

The same will be true of the brake lights and regular taillights, though I already have enough red LED's to build those.

All of the turn signals will also be steady marker lamps that will activate automatically at a much lower level when it's dark enough, including when I go into shadier areas and tunnels and whatnot, just to make me more visible. The taillight and headlight will generally be on all the time anyway, even in daylight, because they are already bright enough to be visible enough to catch the eye (as daytime running lights or headlights on cars do, which I like when I see them, as they help *me* see oncoming traffic I might not otherwise see as soon due to road conditions).

This is the switchbox I'm using right now to control the lights. It's from an old Hampton Bay electronic ceiling fan control that mounted in the wall in place of the lightswitch. Two of the switches were momentary-on's, and one is a standard on-off switch, with both normally-on and normally-off sides available inside it. I'm currently only using the righthand standard switch to control headlight/taillight, but had planned on using the momentaries for the turn signals, on a 15-second timer (or thereabouts). Now I have an actual 3-position switch in it's own ring-mount off a scooter for the signals, plus a horn button (and a dinky horn), so will probably ditch this whole switchbox later, once I build a mount for the keyed switch for headlights/power/etc from the same scooter. A bit of silicone around all it's edges and the holes in the back, and around the switches and their rockers made it watertight as well, again proven by the recent rain-soaked trips.

Now here is the Plan B (version 1.2.1) bike, based on my Kensington frame. First pic is the handlebars showing my radiator-hose-clamp mount for the "headlight", which is actually just 1 of a $10 set of water-resistant LED flashlights from Walgreens I'd bought a long time ago, and rarely use this one (it's 3 AA batteries, so it's a bit long for a pocket light). The metal casing makes it durable enough, and the switch is a rubber dome, which I left pointing downward to minimize the chances of water pooling on the membrane and leaking around it.

The duct-taped item hanging by wires is the window-motor switch off the Ford. I just did a quick wrap of the tape around it to keep some water out and to hold it all together during the tests; it's left hanging so I can use it with either hand, since I have to hold the switch on against a reasonably strong spring (it's a power window switch; they're made to not come on accidentally) so my hand gets tired in less than a mile. A better switch will be forthcoming once I build the throttle grip, and build a controller instead of just either on or off for the motor.

That throttle grip will be another "key" for the bike as well: Instead of putting the magnet in a rotating cuff, and a Hall-effect sensor in the throttle mounting ring as many systems do, this will have the Hall-effect sensor mounted in the handlebar grip rubber (a silicone-filled patch in a cutout area of the regular grip will keep it watertight), and a magnetic strip along the palm of my glove will activate it. No one will be able to engage the motor at all without it, and unless they're reading this blog, won't know it's designed this way to even try a separate magnet on that sensor area. As I rotate my hand around the grip, it will go faster or slower. Just moving my hand a bit off the grip, or up or down the grip lengthwise, will stop the motor power entirely, so when I reach for the brake lever , it would take my hand far enough off the grip to deactivate the motor, for instance. I've tested the theory with a sensor, a small harddisk magnet in the glove, and a multimeter reading the sensor output, and it should work fine. The harddisk magnet has a very closely-held field, unlike the average magnet whose field can still be fairly strong some distance from it; this is the basis of how I came up with the idea to cut off the throttle just by moving my hand away.

With this, there are no "stuck throttles", which I've had happen several times testing the scooter's throttle grip. No "scratchy pots" either, which can happen with some of the potentiometer-based throttles. No moving parts, just my hand, a magnet in a glove, and a sensor glued in place in the grip. Like magic. :-)

This is an overview shot of the motor, mounting, and drivetrain of the Plan B bike. The motor is mounted on two thin blocks of wood (leftover from when I did a conversion of my waterbed's "box spring" section to a frame to hold it higher off the ground so more drawers could go underneath it), which are mounted to a piece of aluminum cut from a scrapped out patio door frame someone threw out. That frame has been very useful on the bikes, as it has an open section where the glass was held in that fits over all the thin tubing of the rear frames tightly, and can then be clamped to the tubing easily.

In this case, I used two more radiator hose clamps, and tightened them enough to partially crush the aluminum against the bike frame (which is steel), so the motor can't jerk the mounting loose or change it's angle, since I have nothing else stopping it from rotating around the tube besides the friction of the aluminum against the bike frame--it's only a test bed, so permanent mountings would be a waste, especially since I'll have to change the distance and angles sometimes for different motors, mounts, chains, etc.

The blocks of wood make mounting motors with bolt-on points easy, as I can just screw them to it with drywall screws for test runs. The scooter motor was made with such a mounting option, and that's what I used first on this bike, to a reasonable degree of success despite the condition of the motor.

A better-lit shot of the mount, from slightly above.

Here I also had to use JBWeld to hold the scooter's former wheel chainring onto the hub and spokes, though at least on this chainring I had space and mounting holes for bolts to run thru the entire wheel. Those bolts are themselves also JBWelded at each end, to add a bit more strength. Definitely need a machine shop for this kind of thing.

What would have been perfect would have been being able to use the scooter's freewheeler, but again it's made in the wrong direction to use here, and worse was that I couldn't even get it off the scooter's wheel. It's *very* tightly threaded down onto it, and the dissimilar metals may even have oxidized together--I can't see in the threads to tell until I can get the thing off the scooter wheel.

Also, because of the way the freewheeler is made for the scooter wheel, I *might* be able to mount it on the bike's left side without mirroring it first, by putting it on backwards (relative to the side of the bike it's on), keeping the freewheeling direction correct. I don't have that option with the bike-type freewheeler, because it has multiple chainrings on it, not just one, so mounting it backwards like that would mean the larger chainrings would interfere with the bike's frame, not to mention the space needed for the chain itself, and clearance for shifting the chain from ring to ring. The scooter's freewheel mounted this way would just barely allow the very large single chainring, plus the smaller-than-bike-version chain to clear the bike's frame.

Lots of ideas, not enough tools or materials so far. But I've still gotten things to work for testing, at least, even though I wouldn't expect them to last all that long in actual road use. We'll see how long they do last, though, since I really can't proceed any further with new designs without a different motor and a fair number of tools I don't have yet (and won't be able to afford for some time to come--useful machining tools are one thing it's very hard to find scrapped out).

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