Fifteen Years After...

Believe it or not, this 'scope has been transported overland for over 20,000 miles...(that's when I stopped counting) to star parties, benefits, public educational forays, "Into-The-Bush-Expeditions", camp-outs, festivals, you name it; and all in the back of a Mazda!. And, yes, it finally did the unthinkable...it broke down.

One afternoon, I lifted the OTA by the rocker box...and the tube slid down inside it, hitting the base with a THUD! My heart stopped beating, I'm sure, for a few seconds, as I thought, "OK, that's it for the primary mirror."

I was wrong. Believe it or not, after a two-foot drop, the mirror was undamaged! Now, the task was to tighten the fit: it seems that the plywood rocker box had shrunk a bit after years of outdoor all-night use in all sorts of climate, and the tube had probably compressed a bit as well, as the tube rests inside the box by virtue of a slight, very slight compression fit. What to do?

When the box/tube assembly was fabricated, I, in my wisdom (cough-cough), had made it so that the top side with the carrying handle could be easily removed; all one had to do was remove the putty from the countersunk screw holes, unscrew the top, shave about 1.5mm off each side of the bearing sides of the rocker box, replace the top, and repaint.

It worked like a charm.

There are some virtues with Simplicity, Thoreau's old friend...or, as the Olde Scots Plumber used to say, "The more kinks and twists you put in the plumbing, the easier it is to stop up the pipes!"

And re-collimated and re-aligned, it's fit for another 15 years, I hope!

Below is a visual record.



The Great Rocker Box/OTA Repair

The top screws cleared of putty, the hold-down screws came off
fairly easily. Unfortunately, though wrapped in plastic, the tube stuck to the
rocker box inside top a bit where the plastic had creeped down the side of the tube over the years.



The countersunk screws



Off she comes!



A little damage


Plane down the sides, putty up, and sand!


Look, Ma, no holes!


Complete!



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