Observatory build: Lights and drives:

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Friday: I have ordered a long string of 100, low voltage, red LEDs and a couple of red E27 LED bulbs with low Wattages. The band type LEDs are cosmetically neater [and brighter] but I want to hide the LEDs out of direct line of sight under the octagon's surrounding woodwork. Unless the LEDs are particularly dim and then it won't matter.

The "Xmas tree" style wiring provides much greater flexibility in siting. The small 230V LED bulbs can be stealthily deployed 'downstairs' to light the way to the observatory stepladder without blinding me.

I built a temporary 'Xmas tree' of AWR[Technology]UK Goto drive boxes on the southern side of the pier. The cooling fans of the AWR resistance box are so noisy and irritating I wanted to put some some distance between us. I have clipped the cables onto the temporary, plywood, pier cladding to avoid tripwires.

The 18mm plywood was supposed to be BWP flooring grade but immediately became wavy in damp weather. One day I shall get around to replacing it. Though it is strictly a cosmetic issue rather than structural. So I could slit the raised waves and glue them back down before painting the pier for a smarter look.

Having the drive electronics working allowed me to check the telescope balance and stepper motor drives. The motors are sounding rather rough after being under cover for many months. These motors stall [very noisily] if they meet any resistance. Though usually, only in Slew mode. Of course Gotos are also carried out at Slew speeds so stalls are to be avoided.

I have turned some shorter, tubular brass, counterweight spacers to re-balance the telescopes on the mounting. The three 5kg weights are a smidgen too heavy. So that sometimes the drives have to work "uphill."

I added a second tube balance rail. This time on the 7" OTA. Slacking off the clutches on the wormwheels proved that my earlier imitation of balance was rather far fetched. Once completely free of friction I was easily able to balance the telescopes and Polar Axis properly.

Once close to balance I find it most beneficial to give the telescope a larger push than strictly needed. Just to see if it continues to travel further in one direction than the other. Following careful balancing the occasional noisy stalling on Slew then ceased.

Stripped of the outside ladders the observatory can finally be seen in all its glory nakedness for the first time. A day of rapidly changing weather. Showers one second and just as brief sunshine the next. The 7" refractor's dewshield cap can be seen peering out of the temporarily open, observation slit. The more modest 6" is snuggled just above.

Thanks to IKEA for their all stainless steel clothes rails. Though the latest model is a flimsy thing compared with the sturdy original. The later examples being smaller in diameter, with tiny support bracket and tiny screws in each end. This makes them sit far too close to most surfaces to function as a towel rail, or whatever.

I deliberately placed the new balance rail on the opposite side of the OTA to the 6" refractor to reduce torsional imbalances. Thought the 6" is much heavier than my paltry, tube balance weights, of course, it may still help the dynamic balance.

Click on any image for an enlargement.

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