Monday March 3, 2003 11:35 PM
Dino Surgeon

Tonight was the guys' night out around here.

Ruth had bunko so Isaiah and I were on our own. I had mentioned something about perhaps the two of us going somehwere for supper to Ruth yesterday, but hadn't formally consulted with Isaiah before I left for work today. Ruth asked him where he might like to go and I wasn't surprised when I got home from work and she told me he wanted to go to El Mezcal. That's just about his favorite restaraunt. It's usually his first choice, anyway.

So after we dropped Ruth off at bunko, we went to a "surprise place" which was actually just Target to pick up something Ruth needed us to get, but a pleasant surprise to Isaiah since the toy aisles there are fairly decent. Of course, we were just in that very same place yesterday afternoon slowly meandering up and down those very same aisles for far longer than I wanted to be, but it made him happy and we had to go there anyway.

After Target I was getting hungry and Isaiah was getting "somewhat hungry". I tell you, I am amazed at the way he just seems to pick up and use adult words. I'm fairly certain his conception of the meaning of many of them is kind of fuzzy, but you sure couldn't tell by his use of them.

We had a good time at the El Mezcal. I can't remember exactly what all we talked about, but I know we discussed the operation of the neon sign in the window above our heads and that we talked about having another "in the van picnic" like we did at a rest stop on our drive to Dallas to visit Uncle John last year.

The best part of the evening was yet to come, though. I told Isaiah that when we got home we'd assemble the motorized wooden tyrannosaurus Rex that Grandma Joanne had gotten him for x-mas. At least twice a week for the past two months he's been asking me if we could put it together and I finally decided that our evening together would be a perfect opportunity.

So when we got home, we got out "Motorized" as Isaiah has been calling it and we got together some needle-nosed pliers and #1 and #2 Phillips screwdrivers and we commenced to bring life to Motorized like a couple of mad scientists. Of course, we had rock out music playing as we worked at the dining room table. Isaiah was about as helpful as a kid his age can be with something as complicated as the dinosaur was.

"Please put that down, Son, we don't want to loose the small parts."

"OK. Can I hold the arm, then?"

"I suppose, but be careful with it."

"The instructions are all folded up for you now, Daddo- right over here."

"Eh, thanks, Isaiah, but I kind of need to look at them..."

"Oh, sorry. Here you go. Can I hold one of the screwdrivers?"

I am quite familiar and comfortable with his help, though. I'm not sure how I'd even complete such projects without his particular brand of assistance anymore and we got Motorized all built with only one mishap. One of his cheap Chinese plywood legs broke right in two when I dropped it from a height of about 5 inches onto the dining room table. After I completed the assembly process, though, his broken leg was made good as new by the judicious application of a dose of cyanoacrylate adhesive treatment (that's super glue for you non-dino doctors out there) and he stood before us in all his ferocious glory.

Then I got the last two AA batteries out of the junk drawer in the kitchen and HUZZAH! Motorized was walking, growling, and swinging his head back and forth as he scanned the pre-historic terrain in front of him for prey to devour. And then he wasn't walking, or swinging his head and the pitch of his growling had gone up to a whine as the worm gear that powered his main flywheel fell out of alignment under the stress of motion.

I was dissapointed, but undaunted. I was also glad Isaiah was upstairs at this point being assisted by his now-home Mommy in the process of getting ready for a bath. Come on, I thought, it's two gears and a worm gear attached to some linkages. It's ingenious in it's simplicity. I can fix it with no problem.

I let it run unloaded for a few moments as I held it in the air to determine the source of the malfunction. Aha- the main flywheel has too much endplay in its shaft. I considered some kind of spacer, like a washer or something on the proper end of the shaft, but then I came up with a simpler solution and just bent the side of the gearbox housing slightly and everything was back in action! Yahoo! I thought, I am so cool!

But then, being overconfident after watching it run flawlessly on the table for a few minutes, I put it down on the carpet and- of course, the worm gear went out of alignment again and I was back in head-scratching mode. The flywheel was lined up with the worm gear- they were straight on. It must be- yes, that's it. The worm gear was now lined up horizontally with the flywheel, but it did not mesh far enough into the teeth of the flywheel to reliably keep it turning under heavy loads.

I considered possible solutions for the second time. I decided the only thing that would work would be to shim the bottom of the motor towards the flywheel thereby creating a closer mesh between the worm gear and the flywheel. It was a trial and error process with at least three dis and subsequent re-assemblies and eventually required a slight adjustment of the motor alignment hole with my trusty Dremel tool, but I fit four thicknesses of 60lb cardstock under the lower part of the motor.

Once again I tightened all the screws and flipped the switch and- HUZZAH! Motorized was back in action. He growls a little more loudly now, and he'll probly eat up batteries more quickly due to the reduced efficiency of the tighter gear mesh, but he's now got a bulletproof power train. He can even walk on the carpet now though not for long, cause he falls over. Of course, carpet is probably outside his nominal operational envelope anyway.

For curious among you (or, I suppose, the simply bored) I have provided a short movie of Motorized enforcing the borders of his domain in the form of a 208Kbyte mpg.

Medicine is such a rewarding career, even if your patients run on double-A batteries.