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Thursday, December 4, 2008

Cargo Pods, Modular Connectors, and Some Disasters

The new cargo pods, which will replace the baskets, will be made from these aluminum test equipment boxes. I don't know what was originally in them, equipment-wise, except that it required calibration, as the sticker-seals for that partially remain around the edges.

I don't have the original front panels for them, but I do have the sides/top/back, and have a lot of small panels that can be used in place of the front panels (which will now be the top). Those silver-grey panels sitting on top of them will be attached to the outer edge of the case by piano-hinge, and the inner edge will have two IBM AT-case locks (or similar), one at each corner, to hold them shut. They're not theft-*proof*, but certainly *resistant*, as the casual thief can't just reach in and take stuff out, like they can with my baskets. (And did, by stealing my very last two bungee cords, just wrapped around the baskets not even holding anything on, while I was in Jack-in-the-Box a few days ago. I was watching the bike thru the window, seated next to the bike rack, the whole time *except* for the one minute or less that I walked away for a refill. At least they didn't try to steal something more important, or damage anything.

But it motivated me to finally make good lockable cargo pods, which I've had several posts on before, but never made anything beyond the couple of kitty-litter-pail pods that worked ok for a while. I stopped using them mostly because they were such a pain to open and close, especially after the sun had begun to dry out the plastic enough to make them harder to flex around the seals they have. They're also not very roomy--each of the new pods above should be around three to four times the volume of a kitty litter pail. They also won't get destroyed if I lay down the bike--the pails can crack, or get gouged by rocks so badly that they later crack along the gouges.

The vacuum-cleaner-body pods would have looked nicer, but had far less room. I might still eventually finish making those, if only for an instructable on how to do it for those that don't need much room, but do need a tough pod that looks streamlined.

These two pics just show about how the panels might mount. They actually have to go significantly farther back, to allow my heels to clear them, but you get the general idea.

They are so wide and vertically deep that they'll be a bit in the way for really steep-angle turns, if I have to do one, but since I rarely ride fast enough to need to tilt very far during a turn, I don't think I'll worry about that.

They'll be mounted to flat plates that used to be rack-mount ears for some very heavy 10BT LAN routing rack boxes.

Those rack boxes were steel, but the ears were aluminum. I'm trying to use aluminum where possible to save weight and make things easier for me to work on. For the most part, the slightly thicker aluminum I'm using weighs significantly less than the steel plate I'd need to do the same job, and is much easier for me to work with. For instance, I can hand-drill aluminum for field repairs or modifications when necessary, but would have a tough time with steel, using only hand-tools or at best a small 4AA-battery-operated cordless screwdriver/drill.

Here are the mounting panels being marked, drilled, and riveted into place:

You'll see some cutouts in each plate, necessary to clear the axle bolts on both sides, and to clear the rightside's rear shifter cable stop. The rightside cargo pod will have a similar cutout for the derailer, which will waste a small amount of space in that pod. If I could get a NuVinci CVT rear hub, I could ditch the whole rear derailer and cassette, and not have to worry about that. :-) They're a bit on the expensive side for me, though, and highly unlikely to show up used anytime soon.

I first clamped the plates in place to level them out, make sure they all came out straight and level. :-) I just set a flat plate across the top to check that evenness. Then I marked the left side unit with lines, drilled it's holes (using the existing holes from the motor mount brackets first), then used that plate as a template to drill the right side plate, with them clamped together, to ensure symmetry. Then I clamped the right side plate on the frame, lined back up to the left side plate, and drilled thru it's holes into the frame, and riveted both of them in place.

The actual cargo pods will be bolted to these panels, allowing me to remove them if necessary, or to change them to others reasonably quickly. With the heavy loads I have to carry, these will also help prevent side-sway and wobble, which happens to all the common rack and basket solutions I've tried, which only have connections at the seatpost and the two dropout accessory hardpoints. That wobble can cause me to overcorrect when steering, and while no crash happened because of it yet, I'd like to keep it from ever happening by stopping it entirely.

The top of the panels have the rack-mount tabs on them, which I can bolt a top flat panel to for cargo that won't fit in the pods, and can strap down to it. The panel itself I will try to make so it can be carried *in* one of the pods instead of having to be mounted, when I'm not using it. I might not do that, though, as it may simply be more convenient to have always available.

An add-on I'd put on a few days back is a connector so I can detach the taillight assembly from the bike and put it on the trailer.

It's just a pair of old AT-style keyboard extension cables. One (non-coily) I cut the male end off of, leaving about 8" of cable, and that was used on the taillight assembly itself. The female end of that with it's about 5.5' of wire went to the bike itself, wired up to the headlight module and the battery. The female end was used for that so the pins can't be accidentally shorted out against something if it is dangling loose for any reason.

The other is just a coily cable ziptied to the trailer. For the nonce I just zip tied the taillight to the styrofoam fish-transport-coolers I use for carrying the groceries, during that trip. It worked very well; the only bad part was when the chain link broke (unrelated, told below). :( I didn't bother with a mount for it yet, because I will not be using this trailer much more, as I'm building a new one out of the same kinds of materials as the cargo pods.

The grocery-trip ride right before I decided to take the motor off completely, a link in my chain actually popped apart. It's probably one I'd disconnected before with the "chain-breaker" tool, and was looser just because of that.

I found it because it suddenly got squirrely during shifts even when not under load, and sometimes clattered as I pedalled (but not otherwise). When I stopped, I saw what you see in the images above. Had the camera with me, so I took pics. Not something you see every day. Fortunately. :-(

I didn't have my chain tool with me, but did have a small pair of vise-grips and a pair of tiny Craftsman two-setting pliers, so by clamping the link itself into place with the vise-grips, I was then able to use the offset-jaws off the pliers in the expanded mode to squish the pin back into place. The link was tight and didn't flex well but it let me get home without a disaster. :-)

I think that if the motor were working better (well, actually, if the *batteries* were better), it would not have happened, as there would be little stress on the chain. Since I was pulling my trailer full of groceries, perhaps 150 pounds of stuff on it, and had little battery power left at that point, virtually all the pulling power was going thru that chain.

Another disaster that is both worse (in that I can't just patch it together) and yet better (in that it isn't a critical part) is that today, one of my dogs (Fred, the demon-posessed one) somehow got my helmet out of my bike baskets while I was busy elsewhere, and chewed the headlamp off of it. It is pretty thoroughly destroyed. :-( She didn't damage the helmet itself, though. So now I only have the wide-angle CCFL headlight, until I can build a new helmet lamp for distance and spot use.


  1. Regarding the NuVinci, remember if you are going to sell these bikes with cargo pods (which I think is a great idea - see BakFiets at Clever Cycles in Portland) then please know the NuVinci has a 6 yr limited warranty and the hub itself does not need adjustment or maintenance.
    John at NuVinci

  2. Unfortunately that warranty is useless for my purposes, since all my bikes are (and will be) electric-assist, as your warranty is specifically invalidated by use of electric motors to power it.

    I still want to use them for my own bikes, and if I ever could manufacture bikes for sale (which I'd like to do once I have a proven design), I'd like to use NuVinci hubs in them, too, especially for my computer-control-assisted safety bikes, but I'd have to specifically ensure any customer understood that the hub itself had no warranty, as I couldn't get it serviced due to it's use.

    As I've looked more into it, the bars' shifter itself concerns me a bit, in that it appears to be the entire grip, and would prevent a grip throttle from being used. Some customers would want the grip throttle (as opposed to my future safety throttle operated only by pedalling pressure), and if the NuVinci shifter does indeed use the whole grip to shift with, it's going to prevent the use of the grip-style throttle.

    That won't matter as much on my computer-controlled systems that also control the hub's gearing for optimal power use, since they won't have the manual shifter anyway, but it does matter on any bike someone wants to have both.


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