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Friday, March 6, 2009

Rod-End Bearings

Well, I looked around and on the web I can find a few places that have the types I need for an average of about $8 each, but shipping is almost always twice that, except for Ebay "buy it now" and auctions (both of which I'd rather avoid).

Locally I've not had time to call around, but I expect that $8 would be the low end of the price range. $16 plus 8.3% tax is more than I have to spend, so I decided to go ahead and take a gander at the Ford LTD's steering to see what size and kind it actually uses for this.

Sorry, no pictures yet, but I'll try to replace this line with some tomorrow if I have time. Otherwise they'll be in whichever post has further progress on getting them out and using them.

They're not quite as large as I had feared, but large enough--the female shank is at least 6" or 7" long, and a housing of over 2" diameter. The ball itself has the bolt-pin built into it, which makes them even heavier--that is about 3" long. They are very heavy-duty, with a grease nipple built in on the bottom side of the housing (away from the ball/bolt side), and they have a hole in the bolt-pin for a cotter pin to lock the castellated nut down, to prevent it from unscrewing during use.

The really bad part is that they're so tightly mounted that I am having great difficulty unscrewing them, partly because the rods they're screwed onto only have a barely-hexagonal section to hold with a wrench, and that section does not match any wrench I have. I would have expected it to be (like everything else on the car so far) metric, but if so, it must be a 13.5mm, as the 14 is too large and the 13 is too small. None of the standard wrenches fit it well enough to hold it either. Oddly enough only the standard wrenches properly fit the jam nut on the end of the rod against the rod-end, but only the metrics fit the rod-end's flatted area. It's just wierd.

It is necessary to use *something* to grip this rod while trying to counterturn the rod-ends, because the other end of the rod is a ball-joint that freely rotates in any direction, part of the steering control mechanism itself.

I tried a couple of adjustable wrenches, including a small pipe-wrench, but they will not sit flat on the small hexed off area, and won't screw tight enough to hold without slipping while trying to turn.

I finally dug out the vise-grips, but for this job apparently it was too much, and the cheap knockoff no-name-brand ones given to me some time ago just broke, trying to grip it. Fortunately the break is at the rivet hole holding the top head to the grip body, where swivelling is not absolutely necessary to function, so I can weld this piece back onto the tool and still use it.

So at the moment I don't have a good idea to remove the rod-end bearings without damaging something else, which I don't want to do because I might want to use the rest of it for something else later (like the steering setup for the tadpole trike, once I get that far in design stage for it).

Even when I do get them off, I'll have to redo the whole way the steering tabs are setup on both ends, because neither one of them can accomodate this large of a housing, nor can they deal with the built-in bolt-pin the way it is made. Most likely I will still use an ex-handlebar stem on the front, but it will be a steel one that I can weld a flat tab to, and use 1/4" steel plate for the tab. Then I'll make a similar unit for use on the handlebar end of the steering rod, which will mount upside-down. Until I can get the rod-ends off to see exactly what the clearances required are, I won't know for sure what I have to build to accomodate them.

Another bad thing is that since these are so large, they also weigh a lot, probably at least a couple of pounds each, where my current solution doesn't even weigh that much in total.

Monday, March 2, 2009

Fairing Concepts; Second Steering Failure

Sorry, no pictures for the first section of this post; there really isn't anything to show. But there are pictures for the rest of it.

The day after the first ride (last post), I adjusted a few things, then rode it out to the store and then to work, about another 5 miles or so. Just as I was a small block from work, perhaps 1/4 mile at most, the steering tie rod at the handlebar end came off of it's bearing. Fortunately I was not on a street with traffic, as the failure was very sudden and caused instant and total steering loss, and the front wheel just slammed hard right and I ran into the curb and fell over. I just sort of jumped off the bike as it fell, keeping me out of harm's way, and the bike wasn't really hurt by it, but it was disheartening, as it had been going so well up to that point.

I didn't have time to work out a fix before I had to be at work, so I just zip-tied the tie rod eye to the steering tab and gently walked the bike the rest of the way to work. At meal break, I spent about 20 minutes munching and thinking and then deciding I could take the two washers off the large bolts that hold the two halves of the frame together, down at the old-white-fork-to-Magna-dropouts joint, and then put one washer at the bottom of the stack of steering tab - bearing - eye, followed by the small washer and bolt/nut that hold the stack together, so that the new larger washer (bigger in diameter than the inside of the eye) would prevent the tie rod from coming completely off the steering tab. That means that I would at least have a warning of loose steering before complete failure. Once home I could replace those washers with others out of the junk bin.

I still wasn't confident of it enough to ride it home on any streets with traffic, so I only took back roads, and walked it on the sidewalk thru areas where I could not avoid traffic. On one such detour, a fire truck was just clearing up after some (unknown to me) incident at a bar/restaurant and one of the firemen waved me over to him, apparently because he was interested in the bike's headlight first, then other aspects of it. He seemed particularly interested in the horn, and appeared to generally approve of my safety lighting using the turn signals, taillight/brakelight, headlight, and such. I gave him the blog address in case he was further interested in the project, so perhaps someday he'll see this entry and comment here on any specifics he thinks of that particular time.

The rest of the ride home was uneventful, but my arms hurt by the time I got home because I couldn't help but unconciously brace against unexpected failure (even though this would do me no good in such a case).

In order to fix the problem permanently, I'll need to either come up with a totally different steering solution, buy real rod-end bearings, or get a propane tank and brazing rods (maybe the silver solder I have would be strong enough, but I don't know, and I'm not sure I'd trust it enough to try), so I can use the six-holed heating head I have for the mini-propane tanks (like camping equipment often uses) to braze the bearings into the eyes, probably by brazing some strong metal plates across the outer faces of the eyes, over the bearings, with a hole drilled thru for the bolt.

I think that getting real rod-end bearings is the best solution, because the skate bearings have a tiny amount of play in the bearings themselves. As wheel bearings that doesn't really matter, as they're always being pushed on from the same direction. But as tie-rod bearings, they're being pushed alternately one way then the other, while pivoting, and that means any play they have results in wiggle of the whole steering mechanism--a looseness that is not conducive to easy (or safe) steering.

So I'll have to find out who carries them around here, and how much they are, so I can figure out what I can skimp on grocery-wise to buy the rod-end-bearings instead.

As I don't have a solution to the steering problem yet, I decided to work on the fairing concept, as I think I'd like to add that sooner rather than later. The weather is getting warmer a lot faster than I'd like, and one issue with this bike is I'm laying out to bake in the sun, with a whole lot more of my body surface directly in the sun during midday and afternoon, when it's hotter, compared to riding upright. Something I had not even thought of until riding this way. :-( Though I had thought about rain and such, I had not given the sun any consideration at all, which is pretty dumb, given that this is the middle of a desert. ;-)

First, a sketch made while at lunch before heading to work, on the day of the steering failure:

The basic concept is to take flexible rod, such as those strung-together fiberglass dome-tent poles (which I already have some of recently donated to me, that I hadn't thought of a use for yet), and make a frame for the fairing that can flex when brushed up against things, so it doesn't break (hopefully) and is light. Some people have used PVC, or aluminum strips, etc, but that would be relatively heavy. This would weigh little, and should be easy to work with.

I would remove the elastic cord holding the sections together, then glue (probably Gorilla glue) the rods into their metal tie-sections, to make one continuous rod out of a single string of rods. Doing this with two poles gives me the parts for the outer main frame.

Then tying the ends of each of these together, first using zip-ties and then probably wire or a custom-made bracket/clamp, I'd open up the parallel poles into a pointed-end ellipse, as shown in the pics. Straight cross braces will hold it apart near the ends, then curved X-braces, one near each end, would create the curved top shape and strengthen it as a whole.

I had planned to make the cross braces and x-braces out of the tent poles, too, but they're not able to be bent that far safely. :-( I discovered in my experiments today that they will do fine for the gentle curve of the outer edges, but for the tight curves over the top to give the dome shape they are unsafe to use. I have to put them under such stress with that tight curve that even a *little* extra push will snap them suddenly and violently, in a spray of fibrous splinters.

So I'll have to use something else, probably thin metal tubing, to make the top curves, and I don't have a way to reliably bend that kind of thing evenly. I'll have to make the tool to make the part to make the fairing frame to make the fairing itself. ::rolls eyes::

The 2 and 3-liter soda bottles I've collected will be cut apart so I have all the flat middle sections laid out in squares/rectangles, then they'll be stapled together at their edges. I'll probably have to take a stapler apart so I can use the bottom half underneath to recurve the staple ends, as I won't be able to reach the length needed to get to the edges needing stapling any other way, with a normal stapler. I might also use a very thin line of Gorilla Glue or something between each edge and the next, to help spread tension from the single point-holes where staples pass thru to the entire surface area of the connecting plastic, just so the staples don't tear thru from any pulling/pushing on the surface by wind, crashes, handling, etc.

The way they'll overlap will probably need to be determined by airflow direction, rather than rainfall, as the airflow will be there anytime I'm riding, but rain will only be occasional. I'd rather live with some water getting thru than having airflow catch on edges and lift them up, causing drag. It'll be bad enough just because it will not be a full fairing, only a front and top.

Then I would lay out the sections of plastic over the X-frames to create the first sections of curve, and most likely simply staple them to themselves, folded over the outer left and right edges of the frame. Then all other sections would be stapled to those sections, until I have the shape I want.

At that point, the assembly will be ready to bolt to the bike itself. It will mount to the front headstock, or rather the frame just behind that, so the front wheel/fork will pivot within it but not touching it. This means my lighting will at this point be shining *thru* the plastic, and I'll get glare back at my side of it, but since the plastic slants downward at this point, it should not be too bad. Eventually I will mount the lights on the outside of the frame, or *just* inside it so that they are on the frame against the inside of the plastic, and thus reflections or glare won't be an issue. Same thing is true of my headlights, both the front fork unit and my helmet light. The helmet light will simply be that way always, but usually it's only really needed to the sides, before and during a turn especially, and when it's pointed straight forward it'll be shining on a very downward-reflecting section of the plastic anyway.

At the rear, it will mount behind the headrest, so that the top of it is not far above my helmeted head when I'm sitting up in the seat, feet on the ground. That's the tallest it needs to be. There'll be plenty of clearance when I'm sitting back riding. The part directly above my head will likely be made from the green plastic bottles, to provide a little shade, and I might end up foiling that section over using the inside foiled sides of various food packages, simply stapling them to the plastic as needed, and replacing them when they degrade from sunlight/etc.

Tiny mini-rant:
I started this blog in hopes it would generate communication between those interested in these types of projects, including those doing them themselves, as anyone can leave comments on any post, and I'll reply to them if needed or wanted.

However, hardly any comments have been left--most that have were thoughtful and helpful, though not all, and there have been a handful of spam comments that were moderated out, but those were not even related to anything on this blog. I appreciate those that have left comments, but wish more readers would, even if it is not much. Especially anyone with questions, please ask away. If nothing else, just knowing *someone* is actually reading this blog and finding it useful or helpful in some way (or even just entertaining, watching my continuing stupidity in stubbornly doing all this from recycled materials and whatnot) would be encouraging.

I'll continue blogging even if no one replies, as I do know there are people out there using this information, being helped in their own projects by it, even if it's only the one I already know about for sure. :-)

One problem with this type of project is that I have no one at all to turn to for help if I can't fix or make something, or don't have a tool I need for some part of it. I often can make do, or find a workaround or another way of doing something, or just make my own tool in certain cases, but often it would be helpful if there were others interested in doing this kind of thing not as a group project, but more "Do It Together" instead of "Do It Yourself", because the former can be far more fun than the latter.

About all the latter really does is give me the right to say "I made this!".