I can has shenanigans?

So I fell back into a phase of “Oops, didn’t bring the camera” syndrome, but here’s some of the goings-on for the past two days. I’m pretty sure that my left arm is going to fall off on its own and beat me to death just by itself soon. There’s been alot more threading and tapping. It builds character….and muscle, since it allows me to try to equalize the arms a bit. Being right handed, my right arm has historically been a bit stronger than my left.

Anyways, onto pictures.

More progress on the steering arm, now with 99% more gears! They are all some ungodly large pitch (10? 8? Module 3?) and 3/8″ in thickness, and all waterjet-cut.

I have watched the pile of 50-pound bags of abrasive sitting outside the waterjet room slowly get smaller over the past week. I wonder how much the machine weighs with a full tank of water and sand?

A closeup of the geartrain. Yes, I know, two of the gears don’t touch and two more have very little contact. This was a design error that was corrected by recutting those gears.

The total ratio is around 40:1.

Random closeup through the Lexan mount. I suggested running the gear teeth in with polishing compound to smooth out the sandblast-like finish of the waterjet, which probably pitched the efficiency out the window. They haven’t taken me up on it….yet.

Switching gears a little bit, I did some more cutting and subsequent assembly work on this parking stand for the scooter. It does two things – allow the front wheel to lock against something for leverage while folding, and also allows the vehicle to rest vertically, leaning on the Wolverine-claw-like things (Which will actually have a plate mounted on top). It’s missing a few parts, but that will be addressed soon.
The big difference between this piece and the steering arm is that this has right angles and hence was easier to slam on the drill press and drill quickly and accurately.

Hmm, so all this fabbing has distracted me a bit from wheelmotor work. My magnets and bearings both arrived today.

Interesting thing about these bearings is that they’re tiny. 15mm bore, same as the previous, but only 24mm diameter and 5mm width. I’m slightly concerned about loading and bearing life. Whatever, I suppose. I should be able to get some work on the side plates done tomorow (today? what week is it!?.

28 magnets test loaded and…. HEY! What’s that giant gap?! It’s supposed to be a perfect fit!

Oh well. Nothing some index cards can’t solve. Did you know that a full circle of magnets like this can actually be detrimental to efficiency becuase of increased hysteresis losses in the core?

Stay tuned for the next episode. Meanwhile, bot on.

More shenanigans… and a Snuffles Reloaded update.

Starting from now, I’m going to post mini-pics in 512 pixel-wide preview mode and then the linked pictures will be at 75% camera resolution. I realized that thumbnails suck, and a 512px preview didn’t do much for a 1024 pixel picture.

Anyways, the box of aluminum puzzle pieces turned into…

One of the steering arms for the 4-wheeler. The wheelmotor pod will sit on the end, and will be able to swing about 200 degrees or so. The steering motor mounts in the circular cutout, and there will be a reduction geartrain running through the arm itself (the Lexan plate is a placeholder, but may actually be used). The whole thing mounts to the chassis through the flat plates on the left.

Mating holes drilled and tapped. I took this one, and both regret it and am glad I did it. Some of the holes didn’t quite line up, and there were enough awkward angles that a drill press couldn’t be used. So it was hand drill, clamps, and alot of patience. The screws are temporary and will be replaced with hardcøre cap screws later on.

So now that I’m twice as buff because of all the hand-tapping, I should do the rest… hey, it’s Spring Break, after all. Gotta look good for the ladies.

Here’s a closeup of the steering gear. This is the waterjet on a good day (and on slow, ultra-fine finish mode). Even without a tilting head, it does great on 1/2″ aluminum.

Update: In fact, I like it SO much that I made part of it into another rotating site banner image. Hit refresh enough and you might get to see it.

And now for an intermission. After the great threading ordeal was over, I decided to head over to MITERS with my 4″ steel pipe and try to turn it into a 3.25″ steel pipe. I was a bit iffy about shoving such a large piece of stock onto the lathe, and tried a few ways. It ended up turning (teehee) out rather well.

First pass. Lots of chatter and earsplitting noise, due to two factors. One, I’m using the wrong bit for the job and the tip is far too angled. This problem was overcome by rotating the bit such that the left face was flush against the end of the pipe, which closer approximates how you’re supposed to do it. This solved the chatter issues.

However, the lathe has only 3 speeds: slow, medium, and fast. And slow is not slow enough to turn a 4″ steel pipe (surface speed-wise), so I was actually cutting almost twice as fast as I was supposed to. But it’s a carbide bit, which is supposed to allow a ~100% increase in machining speed…. so maybe it balances out.

Almost there. There’s still a bit of chatter, but most of it was overcome by a slow power feed, light cuts, and plenty of cutting fluid automatic transmission fluid mixed with differential gear oil. It took around 20 passes in all to reduce the diameter from 4″ to 3.245″. I probably could have done it in less, but wanted to tempt neither fate nor the robot gods.

During this time, I generated so much smoke from the cutting that when I finally turned around to look, the room was hazy. Naturally, not wanting to set off any alarms, I opened all the doors and windows as quickly as possible, and waited for the cloud to dissipate.

So, now that 10 years have been taken off my lifespan, the One Ring is done. Dimensionally, everything is within .003, which is freakin’ good enough. The ID, however, is a bit too large by about a quarter millimetre 0.01″. Which is actually beneficial, since that 0.2mm air gap was a really, really tight goal to hold anyway. I’d rather have some more space.

Now, onto the artifacts. For some reason, I find lathe-curl dynamics rather amusing, and have been in a contest with myself to generate the longest continuous lathe curl. My record with a 3″ aluminum round has so far been 25 feet, enough to stretch across the MITERS room and back a bit. The steel didn’t want to draw out as much, but was still cool to look at.

These were from boring out the ID of the pipe with my not-boring-bar. They would clump together inside the pipe, bob around, then when I pulled the tool back out, would roll out and fall onto the ground. They were nicknamed lathe hairballs by the other MITERers.

Here’s one of the ginorm-o-curls I’ve been looking for. Somehow, they find an island of stability in the clump that gathers by the bit, and then extend straight out and form very wide curves, which then proceed to get tangled in everything. I had to stop this cut because I couldn’t reach the levers any more. Without pushing aside razor-sharp, oil-covered smoking steel slivers, anyway, which doesn’t turn me on at all.

And now I present… the Mass.

This is the conglomeration of all the curls from all the OD-reducing passes from the night. Each pass resulted in a big clump of curls, so I just kept piling them on…. and on…. and on some more. Average 12oz WD-40 can for scale.

It has an enthralling iridescence that the camera flash drowns out. There’s all shades of colors, from purple to blue to blue-silver to plain silver and dull gray, but blue is predominant. Part of the reason, I think, is the sudden cooling of extremely hot steel slivers by the oil I dunked the whole thing in. I effectively heat-treated the curls. A process like this is used industrially (and more carefully…) to make hardened steels.

The only fitting fate for such a clump is, of course, as decoration. It now sits on the tool shelf, monitoring all in the room.

So, tomorrow (today!) is Sunday. Will I rest on Easter Sunday? Nah, not even that’s enough to get me to stop building things. The ML guys will probably be off, but I’ll be working on the side plates, hopefully. Magnets are due to arrive by Monday or Tuesday along with my bearings.

Something better move by the end of the week, or I’m going to be pissed