Ad Astra Observatory

Some nights I just go a little crazy.

My new RA worm showed up today. It is seriously bright and shiny. I can only hope this fixes all my PE problems.

I decided that I wanted to get the bearing blocks as correct as possible before installing the new worm. Now that I know what I’m looking for, by the way, I can tell that the Dec axis is going to need shimming, too, if I get around to it.

Back to RA. After shimming the outer bearing block with stamps (only 4 this time — hmm), I checked the ammeter. Not much improvement, if any, over last night. But I feel better knowing that the worm is more or less inline with the gearbox now, and that it’s parallel to the worm mounting plate.

So I decided, being impatient and still having energy left, to install the brass worm. No problem; took 2 minutes. Uninstalled the steel worm, it’s still got grease on it (need to clean that someday), installed the brass worm, greased it up, and decided to run it in a little.

Everything was going fine until I found The Spot on the RA axis (note that the axis isn’t carrying any weight at the moment — the Dec axis is removed) where the worm made a Bad Sound.

I decided at this point (and this is where the crazy comes in) that I would swap the RA main gear (aka the worm wheel) for the Dec main gear, to see if it was a little smoother.

I don’t know if I mentioned it, but about 2 months ago, I tore down and re-lubed the RA axis. Removed all the perfectly fine but strangely metallic-looking grease that Scott Losmandy put in there, replaced it with my ever-so smooth white lithium grease. yum. It was a nice weekend project involving paint thinner and an old toothbrush, and I enjoyed myself.

…

but it was enough work that I decided to do the Dec axis “at a later date”.

So. Here I am. 10:30 at night. I’ve decided to do “brain surgery” on my mount. And the Dec gear is covered in metallic-looking grease. Oh, no.

OH, YES. Drag out the rubbing alcohol and the old toothbrush, and bada boom bada bing, I have a clean Dec gear. Now I’m decently covered in grease and the gear is clean, so I lube it up, uninstall the RA gear (with white lithium on it), put that temporarily onto the Dec axis, and lube up the (former) Dec gear teeth with white lithium. I also decided to remove the brass worm from the RA axis at this point; it had been pulled out of the way to uninstall the old gear, but I retained enough sanity not to push my luck too far. So, mount ready to receive, gear ready to go.

…

I found out 10 seconds too late that I should have re-greased the inside of the (new) RA gear, too. It jammed about halfway onto the RA axis and would not budge until I pulled out a breaker bar in the form of a Vixen-style rail for the C9.25, still wrapped in bubble wrap (so as not to damage mount, gear, or bar), and whanged it off of there. No damage to gear, bearings inside the gear, or RA axis. I checked, carefully. (Did I mention I went a little crazy?)

OK, lesson learned. Lube the inside of the RA gear, install it carefully. Rebuild the RA axis (really easy on the G-11, barely need tools to do it. This is a Good Thing). Carefully re-install the brass worm (I’m getting pretty good at the little spot checks – U-joint straight, teeth meshed almost until they bind, bearing blocks pushed together).

Boot up the mount, drive the RA axis around to get the grease all integrated (by the way, for some reason my white lithium grease is turning grey — might be some residue from the old grease, or some reaction between brass worm and steel gear… dunno). There turns out to be one ugly spot on the new gear, too, but it’s small and I think I’ve tucked it away in a place that can’t be reached (it’s currently tucked under the saddle plate, but I think the gear can rotate independent of the axis if the clutches are disengaged…).

Other than that one spot, things are pretty nice. ammeter stays pretty steady while slewing, still jitters across a ~20mA range when idling.

So I had to decide how far I wanted to take this tonight — I want some guiding data from the brass worm, just to get a baseline. But at this point, the Dec axis is in pieces on the floor, I’m covered in grease, and it’s slightly after midnight.

So I decided to get the mount ready to receive a scope, but not to install the scope. I put the Dec axis back together (note: Dec gear now has white lithium, but rest of Dec has metallic, including the worm itself — I suppose I could swap in the lithium-covered worm — didn’t think of that until just now; apparently I’m a little tired). I bolted the Dec axis back onto the RA axis, got it to CWD position, and shut down the mount.

Cleaned up the observatory as much as possible and headed back inside for the night. Tomorrow is another day, and tomorrow I should be able to catch some photons in the form of a guidestar. Tonight was a 4-day moon.

Here’s hoping that the new worm makes all the difference. Oh, and the stamps. Can’t forget the stamps.