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Friday, April 18, 2008

You'd Think I Made The Trailer To Carry Bikes

Here's a few different bikes in the trailer, just to show how a happy accident of design worked out very well for carrying them, especially with the rear wheels taken off.

First up is a the pair of bikes I picked up on the windy day; I don't have the wheels on them at all, since I took them all inside to clean and inspect them (bearings, etc) the night I brought them home, and was so tired and sick I didn't get that done yet.

This is an old 700c 10speed I got in the original pile of bikes I'd gotten as scrap back in an early blog entry. I've done nothing with this one yet, because it could be used as-is, once the rotted out rubber tires and tubes are replaced, and all the bearings cleaned and lubed. The chain is so rusty it will probably have to be replaced; I doubt I'll ever get it freed up. But even it, the largest bike I have, fits on the trailer, with the rearwheel popped off so the rear triangle will hook into the space between the flat bottom of the trailer and it's rear support frame bar.

This is the test bike, just set onto the trailer, with both wheels still attached; just to see if it would fit that way. I'd have to be extra careful about tying it down if I did leave the wheel on that way, so it doesn't roll off the back end. With rearwheels off, bikes stay in the trailer fine with just normal tie-down.

Why the DayGlo Avenger look?

Here's a little bigger/closer pic of the trailer itself. You can see I didn't do a very good job on the paint; unfortunately it was already windy when I started that, so it's not very consistent, and then I ran out of primer halfway thru when the can's valve stuck shut. I still needed the dayglo paintjob for the trip, so I went ahead and did that over the primer as much as I needed to to help the visibility, since I think I'll have to redo it all anyway later on. Interestingly enough, if you look at the full pic above, you'll see I somehow managed to park it almost on top of the marks in the grass where I had done the painting before I left that day. Very strange.

As you can see, it's a LOT more visible than in it's original colors. The nighttime pic with flash, at about the same distance (just cropped differently):

And the new paintjob *at night* is still more visible than the original colors even in the daytime pic without flash

So you can see why I prefer the dayglo paintjobs on my bikes and gear. Speaking of which, I've never posted a pic of my gear, so:

All of the gear except for the vest were bought at various times at Deseret Industries thrift store; I think I paid at most $1 for any item. Some, like the elbow pads, were half that a pair. The vest I picked up for another buck at somebody's moving-all-must-go sale on the way home from work one day. The reflective strips are cracked and peeling a little, but as you can see in the camera flash, they still work fine. Keep in mind that the only light in the pic is some indirect light from another room with a 15w fluorescent tube in it, plus the camera flash. So that gear is pretty dang visible. In daylight it practically glows.

The elbow and shin/knee pads were black when I got them, and black might look spiffy but it's damned hard to see at night, and not good in the daytime since it absorbs heat/light much better and makes me hotter. The helmet was white with a bunch of black markings and decals on it, so I peeled and sanded them off for more white surface area (and because I'm not advertising a bunch of rollerblade manufacturers for free). The gloves were snowboarding gloves, I think, and came in the colors you see. They also have liners to keep hands warm, but I sure don't need those in the weather we have now. :-)

The helmet I also attached a clip-on taillight too; it has 5 flashing patterns built in, but I only use the one that flashes all 5 LEDs at about 2Hz. That uses 2 1000mAh NIMH AAA batteries for around 120 hours of service per charge. The headlight is a miners-type bike light, minus the straps, originally epoxied in place but apparently the epoxy won't stick properly to even a very-roughed-up surface on the plastic it's mount is made of (HDPE, I think). So I ended up using doublesided foam tape, and it's held on very well since then, surprisingly enough. It's got 6 white LEDs that can be turned on in 1, 3, or all 6, with a battery-munching krypton bulb in the middle that can be switched on in place of the LEDs. I never use that, because I only get about 12 *minutes* life out of the three 1000mAh NIMH AAA batteries I use in it, as opposed to over 60 hours with even all 6 LEDs on. It claims a 200 hour life for battery using the LEDs, but that only works out if you use just *one* LED, or you don't care that you can barely see the LEDs at the end of the 200 hours in an otherwise pitch-black room. :-)

Since I didn't like the black pads, I primered and painted them when I did the bike. I had actually done the elbow pads before, using some old RC aircraft paint I'd had laying around for at least a decade and a half, and it worked pretty well for such old paint under such rough conditions. But it eventually was too torn up from impacts and scrapes to cover even half of the black anymore, so I repainted them, too. Kinda wishing I hadn't, now.

The paint is unfortunately pretty crappy; I could not find Krylon (fluorescent versions) at a reasonable price at a place near enough to me to go get, in the last few months; everyone seems to only carry Rust-Oleum instead, which does not work very well on any material I've tried, regardless of how carefully I clean and prep the surfaces, and regardless of temperatures outside. Humidity is virtually nil at the moment, as regards problems it could cause with the paint (this *is* Phoenix, Arizona, after all). The primer doesn't stick all that well even before I apply the topcoat of fluorescent, but after I do that it seems to delaminate quite easily; I can scrape it off with a fingernail! Even on the freshly-sanded bare steel of the tubing used on the trailer it did not stick. It actually stuck better to certain painted surfaces than it did on the bare steel. Also, regardless of how it is applied, via layers or misting or any amount of time between coats, the topcoat will *always* crack over the primer. So that's why the gear and the bike and trailer look so worn and scratched up even after only a week or two since painting (the trailer only a few hours!).

Rust-Oleum will never again be used on anything I own; I'll go ahead and bike the extra distance (about 4 times as far, over 25 miles round trip) to get Krylon fluorescent paint, and the primer to go with it. I've used Krylon paints for more than 25 years on various things, and haven't ever had any problems like these, unless I quite simply didn't bother cleaning the surfaces at all first, and they had oils or something on them. Even dirty plastic with grime and fingerprints on it works better with Krylon than the cleanest, most prepared surface did with Rust-Oleum. :-(

So there was about 60 bucks I didn't really have to spend in the first place down the drain, and I have to spend at least that much again to buy the Krylon. It's gonna be a few months, maybe a year, before I can afford to do that. Next time I get a tax refund, perhaps. If I'm lucky, I'll be able to get Home Depot to take back the unused cans of RO, and I can put that money towards the Krylon, for a paint job that will actually stay on.

Thursday, April 17, 2008

Trailer nearly makes full trip till winds tip over

Yesterday, I went to pick up a couple of small bikes from a member of the Freecycle list, and decided to use the trailer on the roadbike (Columbia), since the test bike is really not in good enough shape to go that far (in this case, at least 11 miles each way), and certainly not as comfy a ride (it has NO shocks at all).

The pic above shows the combo as they were that night a short while after I got home; earlier that day I had just repainted the trailer itself from the various colors of the items it's made of to match the style of the roadbike for visibility. Not many bikes have trailers on them, so I wanted to be as sure as possible that drivers would know it was there. :-)

I "knew" I would be back long before dark, so I didn't put any lighting on it, just the rear reflectors, and a pair of spoke reflectors. Unfortunately, somewhere during the ride, the spoke reflectors seem to have vibrated off without me noticing, since they didn't really fit very well in those small wheels. I'll have to epoxy or silicone the next set in, and not trust the screwmounts. The righthand rear reflector is also missing; more about that in a minute. I didn't actually make it back until over an hour *after* dark, because the winds changed direction during the ride, when I was nearly at my destination. They started out as headwinds against me by maybe 15MPH steady, and 30MPH gusts (enough to tip the trailer up on one wheel when empty several times, though not enough to turn it over until I was almost there--but enough to blow me on the bike into the road and nearly into various vehicles a few times during my southbound trip). When they changed direction at first they died down a lot, then began gusting very very strongly, and that's when the trailer tipped over (taking me and the bike down with it, though I got off without falling). Fortunately, this was in a completely deserted industrial area, with no traffic.

It would not have tipped except that it seems to have a resonance problem: When it starts to bounce, one side bounces first, probably because the wheels' axles are not perfectly aligned with each other and thus one hits a bump just a bit before the other. With the tires fully inflated to 50PSI (where I usually keep my bike's tires at, or higher), then once I reach a certain speed on a road with semi-regular bumps in it (common along the sides where bike paths are, usually from cracks in the road that have been tarred over or repaved but with "ripples" in the surface that can be easily felt at speeds over 7-10MPH), the tires begin bouncing alternately, first left then right, and each bounce gets a bit higher, until it would tip too far if I didn't stop or slow down. I had this problem all the way there, but only randomly, and I didn't figure out why until it actually tipped. In this case, I felt it tipping, but then just as I would have stopped, a gust of wind simply picked up the already-lifting side and tossed it (and me and the bike) over.

That was a problem I didn't have on the test bike, because on the test bike the mount for the trailer is a tube almost the same diameter as the clamp, while on the roadbike I didn't really have time to work one out or move the other one over, so I just clamped it to the much thinner cargo basket rear-handle. That left a lot of play, which solved one test bike problem but introduced this tipping/bouncing problem. The solved problem was that I could not corner well at all, and had to make very very wide turns (as wide as a car or even moreso), because the test bike could not tilt at all during turns due to the trailer holding it level by the mounting bar/clamp. That turning problem was potentially dangerous, because I could never have made some of the turns to get out of the way of unobservant drivers with the large turn radius it forced on me. I have another potential solution for it, but have to see what I've got that will fit the BOM for it.

The solution to the bouncing was to let a lot of air out of the tires, bringing them down to maybe 20PSI instead of my preferred 50PSI. I tried it at various levels before getting that low, but didn't really stop it until they were pretty squishy, that way, and lots of drag because of it. But no worries about bouncing, at least, so I could ride at normal speeds (as much as the wind would let me).

I had, up to this point, been able to stay in 2nd gear on the pedals, and 3rd to 5th gear on the rearwheel. I had to stay in 1st to 3rd on the rear wheel after that, losing quite a bit of speed because I couldn't pull the trailer as easily due to the extra friction from low tires, plus the wind (which at least wasnt' a direct headwind at the time but was still obnoxiously strong and gusting, pulling me and the trailer all over the place). Once the trailer was loaded, and I was against the even stronger winds on my way back, I was down to 1st gear on the pedals, and started out at 3rd or 4th on the rearwheel, but was down to 1st on that as well less than 1/3 of the way home, and wishing I had even lower gears. :( I *really* need to get this motor thing going.

Now, the real problem was that when it tipped, somehow the righthand upper side bracket (orange and white in these pics) must have hit the ground just right because it snapped the weld at the front end of it, away from the front vertical bars on the trailer. The rear weld on it is very solid, and didn't budge, but the front one wasnt' a full-around weld, only 4 points, and it snapped them all in one go. I probably didn't weld them right in the first place; I'm still not practiced enough. Fortunately I didn't need that bracket to hold my cargo in this trip, as I had already planned for the front bar and the rear bottom bar to be the main supports for the bikes (taking their rear wheels off and sticking the triangles into the gap in the bottom bar/mesh area, then hanging the handlebars off the front bar and tying it all down). So it could have been a lot worse, as a warning to me that my trailer needs some more reinforcement "just in case" and my welding leaves a lot to be desired before I use it on an actual bike. :-) The tipping over is also where the righthand rear reflector disappeared, I think, since it had been mounted on the bar with the broken weld (though nowhere near the weld, it probably *was* close to the actual impact point of the bar on the ground, up at the corner, like the left reflector that did stay on).

I tried to take pics of the broken weld, but couldn't get a usable pic at night, and forgot to do so today while it was still light enough. I've not felt well even yesterday (the day before I was sick as a dog most of the day and all night), but had to go get those bikes before I lost the chance to do so; today I both still didn't feel well plus was hurting and exhausted from fighting the wind all the way there *and* back, especially back, where the winds were more directly against my direction of travel for all the last part of my trip, plus traffic was awful even on back streets for some reason, with vehicles roaring past me very close (within inches, instead of the legally-required 3 feet). That made for a very stressful time, because I could not control the bike very well with the wind directly in my face, especially since the gusts would be so strong they would push the bike to one side or the other, and I had to fight to keep it straight and upright while I was at almost zero speed. The loaded trailer actually helped a little, because it's mass kept me from being shoved backwards during strong gusts, even though they often stopped me completely from my very slow progress home. Without the trailer, I would have been pushed backwards, potentially even just tipped over as I tried to stop that (it's happened before in really gusty high winds).

One more thing I need to add to the trailer is a front balance point or stand of some sort, so that when I'm parked I can lower it to keep the trailer (especially when loaded) from pulling the bike off it's kickstand on uneven surfaces. Got some ideas on that, including modifying the kickstand mountpoints that are still on the bikeframe parts of the trailer on each side.

Thursday, April 3, 2008

Better Pics of Cargo Trailer, Smaller Wheels

My previous attempts to add these new sunlight-taken pics of the trailer timed out over the last day or so, so I gave up and created this new post to host them instead. One change I made is that I replaced the 24" wheels with 20" wheels, which gives the trailer a lower center-of-gravity, and also puts it a bit more level when using the current hitch attachment I have on the test bike. I still haven't made a mount point for the Columbia, so no pics of it on the regular road bike yet.

The first is from above and to the right, nothing really new besides the smaller 20" wheels.

Interestingly enough, they actually weigh a couple ounces *more* than the 24" wheels off the Huffys I had been using. I don't like that part, but they're they only 20" wheels I have. I think I'm going to try to snatch up some of the kid's bikes that show up on Freeycycle sometimes, if I can find any that are not in good condition, to use for parts like the very small wheels.

This is from the left side, showing the whole test bike and trailer setup.

From the rear.

This makes it easier to see the hitch connection, made out of the front headstock of a former Huffy, and a stem from another wrecked bike (I think it was a 24").

This pic is from a bit underneath and to the front of the hitch, so you can see the stem mount on the bike's cargo rack tubing (and also my horrible welding to fill in metal that was really too thin for this purpose).

The stem is not one of the typical ones you have to slide the handlebars thru, rather it has a 4-bolt separate plate on the front to allow it to be mounted on any kind of handlebar (or other tubing) design, even those that can't be slipped thru a standard stem clamp. This let me attach it to the cargo rack tubing without any trouble, just under the rear edge of the KLP cargo pod.

I tested it in this configuration on a ride to Safeway today, and it worked out well enough. Since I didn't have baskets or siding on it yet, I just hung the bags from bungee cords across the two side rails on top, and tied some more down to the floor plate with more bungee cords. Even like that, it successfully hauled about 90 pounds of stuff.

Unfortunately for me, there was a variable-direction wind with gusts up to 15 or maybe 20MPH, and at least 5MPH at minimum, so I had a really tough time pedalling home with it, since the test bike has no front shifter right now, and is manually set to the center pedal sprocket. The rear shifter doesn't go down to the lowest 3 gears due to a manual block set on it for a motor test I had planned but haven't finished the motor for, so I couldn't shift low enough to easily move all this mass, especially getting started from a stop. :-( But that's no fault of the cargo trailer. :-)

It did however make me re-consider adding a motor and batteries to the trailer itself, so it could at least help compensate for it's own drag. I had decided against trying that before even building it because I need a way to have it autothrottle itself as I start to pedal, and keep up with the bike but never go faster than the bike, and always slow down exactly as I do, etc. Turns are also problematic, in that I would need one wheel to go faster than the other during turns, and have to have it automatically change power on each wheel to do that, too. I know I don't *need* it to be that complicated, but I would want it to work that way if I did it at all.

Tuesday, April 1, 2008

Bike Trailer for Cargo

I've been working on a number of things, but the only thing worth posting at this time is a nearly-finished cargo trailer I can use on my bikes. I had to wait until I got a welder; now I've got a really cheap flux-core wirefeed welder. It works, but I'm still relearning how to weld at all, after more than 20 years of any amount of practice, and that was with a stick welder.

I figured after a couple weeks I had enough practice to make useful and reasonably safe welds, so I needed a practical project to test the theory, and picked the cargo trailer as one that can be road tested with lots of strain on it if needed, but safe since it's only cargo and not me depending on the welds yet.

I gathered up some pieces of an old computer desk, a couple of 24" Huffy bikes that had seen way better days, some washing machine internal braces, and an old lawnchair/pool recliner that had long since ceased being a chair. Unfortunately, like an idiot, I didn't take pics of everything as I took it apart and started modifying; didnt' occur to me to do so until I was nearly done. :( I'll have more pics attached to this post of various parts that look *similar* to what I used in it, as soon as I can get them in daylight. As you'll see in a moment, my nighttime camera skills leave a lot to be desired.

The first pic shows the trailer attached to my test bike (the Kensington):

The trailer is not very long, it's only about 34" wide from bolthead to bolthead on the outside of the rear wheels. I wanted to be able to get it thru doors wherever possible, but I ended up having to make it a bit wider just because of the parts I had, and not wanting to cut them if I could avoid it (for strength, and to keep from doing more work than necessary).

This is a better-lit shot of the other side and a bit above it, showing it's almost wheelchair-esque layout. It's been tested as a chariot riding around the yard, too, with one of my sisters standing in it, and it survived that ok. :-)

The black parts are computer-desk pieces, while the white ones are lawnchair. The blue and purple were the Huffy bikes. I only used the rear triangle part of the frames, from the seatpost/bottom bracket back. I did use a section of the front of one of the less-damaged Huffy's as my "hitch", along with a neck/stem from another wrecked bike that had a nice bolt-on facing to it, enabling me to easily put it onto my computer-desk pipe frame under the kitty-litter-pail cargo pod (moved to the Kensington test bike from the Columbia road bike in favor of my old baskets, until I get the vacuum-cleaner-bag-section cargo pods mounted on the Columbia, which should be soon).

This is a rear-view of the trailer, unfortunately you can see just how hard it is to see it; I only had one reflector I could bolt right onto it (the others in the pic are on the bike); I have to add another red on the right side, plus some amber ones in front, just to make a bit better visibility until I get the LED's for all my marker lights and turn signals for all the bikes. It also needs the fluorescent paintjob, as does the test bike, but I haven't had the money to buy enough paint yet (I got some, but it had to go to repaint the Columbia and my safety gear after nearly being run over, and picking a gravelly crash to being crushed under the vehicle that deliberately tried to run me down Easter morning just at dawn).

Not much to see in this pic, really, except the general layout and shape. There will be a wire front and sides, like baskets, so I can tie things down and keep them from sliding out, but not give me too much wind resistance (because it is tall, about waist-high). I decided on tall instead of long because I also intend to be able to have my disabled sister ride chariot style in it; she can stand or sit in it for trips to the store, restaurants, etc, since she can't ride a bike herself anymore. Taxis are too expensive for us to take to be able to go places together, but this will let us still do that. My other sister living here will be riding her own bike as soon as I get it put together from the other scrap ones I have. Might have to modify it to fit her, since most are too small or too tall for her. But that's for another post, sometime later.

This is a good side-shot of the "hitch", which works like a U-joint, in that the stem piece is clamped loosely around the rear bar of my cargo rack tubing, just tight enough not to wiggle but loose enough to rotate vertically around it. The horizontal pivot is the former-front-fork headstock bearing, left mounted in the front tubing off one of the Huffys, which is welded to the front of the trailer.

All I have to do to take the trailer off is use my tire-bolt wrench and loosen the nut on the stem, and it'll drop right off the stem, letting me ride off without the trailer when i need to, or quickly hook it up for runs to the store or to pickup stuff found on the lists.

It's a bit easier to see the bolt on the stem in this pic, and you can also see the two brackets on the sides of the hitch stem that keep any side-to-side stress off the welds there; I was afraid otherwise I might end up with them breaking or bending the tubing there (it's a bit thin, as it was only a lawn chair foot that it is welded to right now). Those brackets used to be the front-foot brackets on a washing machine, and are almost 1/8" thick steel. Kinda heavy, but they were right there when I was digging for parts. :-)

I'd like to put a bearing between the stem clamp and the cargo rack tubing, but that would preclude easy transfer of the hitch's bike-end to a different bike, which I could do in about 5 or 10 minutes right now. I decided on this particular hitch method after considering a few that would reach around the rear wheel to clamp or bolt to one of the side accessory holes, or frame, because this hitch can't hit the wheel no matter how tight the turn, and doesn't pull the bike in funny ways down low. It does make for a possible problem if wieght shifts too much to the rear of the trailer, behind the axles of the trailer wheels, because that could lift the stem up and the rear wheel of the bike could lose traction. So I have to watch the load on anything *really* heavy, like a couple hundred pounds or more.

To make this trailer the way I really want to, I'd need thicker tubing more like bike frame tubing, but i simply don't have enough of that available. Thus, the scrap computer desk tubing and the lawn chair tubing, which are probably only 1/16" thick at best. I burned thru them both in several places when I started welding it up, which wasn't encouraging, but I got better at it and fillet welded the holes afterward. Hopefully it'll still be as strong as I need it to be. :-) (I'd practiced mostly on bike frame pieces from bent-up frames, since most things I intend to weld will *be* bike frames).

Better pics will be added above and below as soon as daylight is good tomorrow.