22.01.2021 Spiling an observatory pad and RA drive progress.

 ~~

Friday 22nd. More gales.

My wife came up with a brilliant idea: Spiling. The gentle art of weaving willows into a bank retaining structure. Just like coarse basketwork. I was struggling to retain the edge of the observatory pad. The entire area had been raised by 3' with nearly 30 tons tons of self-compacting gravel. All shovelled into, then trundled manually to the spot using wheelbarrows. Then dumped, distributed and compacted by stamping. 

The expanded footprint of the intended, larger building places the foundation blocks much nearer the edge of the "pad." Without the safety margin of a surrounding path. 

I had been collecting more trailer loads of gravel but it doesn't go far on a 3' high, 45° slope. A row of posts with willow stems wrapped around them, works even for eroding river banks. So it will be fine as a retaining "wall" for much more limited quantities of gravel.

The gently, reverse tapered foundation blocks work best by remaining safely buried. Rather than lifting or even bursting right out of the ground when the supported building is subjected to fierce gales. So a decent mass of solidly compacted gravel is needed around them.

I spent the morning working on the RA drive. The motor sounds much quieter now. Though what that means in terms of the drive performance is still an unknown. 

Several 180°s on the RA and Dec produced no stalls or unusual noises. It takes nearly four minutes per 180° RA slew on the AWR Simple Handset.[Paddle.]

There is still a sense of slight knocking when I move the telescope quickly up and down by holding the draw tube. That's using about 3.5' of leverage. This is with my finger tips resting on the free end of the worm shaft. It is certainly a vast improvement on the visible rocking I had before the latest mods. 

A new angle profile bracket, bracing the motor end, is next. The upstand will be covering the free end of the worm housing. The four, bearing clamping screws can lock up the angular contact bearings if overtightened. Though they still don't provide the necessary immovable resistance of a solid plate.

I opened one dome shutter to have better light. Then had to quickly shut it again because of the nasty gusts of wind. I had already turned the dome slit well out of the wind direction. The trees are all rocking and there is none of the promised sunshine.

 

*