22.11.2021 New skate wheels and dewing.

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Monday 22nd 31-41F. White frost. Early cloud clearing to bright sunshine. I have my Kamik winter boots and winter clothes on.

I have ordered a new set of bigger wheels for the shutter slides. 84mm Ø in the cheapest inline skate wheels I could find. In a set of eight including bearings. These should provide plenty of axle clearance over the aluminium, channel walls.

I also ordered more 60mm Ø skateboard wheels to match the steering rollers on the plywood dome. The number of rollers on the bigger dome rises to 14 from the previous 8. Hopefully the increased number of steering rollers will help to maintain concentricity of the larger dome on the bigger building. See the image of the rotation and steering roller combination. Including aluminium security disk against lifting.

As usual, after a cool night, the optics were dewed. I put both heat bands on full without effect. I have now wrapped the forward section of the main tube, behind the objective, with layers of closed cell foam for insulation. Leaving the last few cm bare to hold the heat band.  

After heating from 10.00-13.00 and using the hairdrier frequently, there was still a 3" diameter dew spot on the objective! Which causes appalling images! The dew scatters light and ruins the sharpness. A wasted three hours of idiocy and optimism!

I have left the telescope at right angles to the sun to warm up over lunch.

14.20 Image of large southern filament shows the dew has cleared. The the bare sections of the main tube felt luke warm to the touch after an hour. 

Now the sun is dragging itself along the ridge of the house. Mushy and wobbling image on the monitor. I am unlikely to get a better image than the first after lunch. I didn't. Another hour wasted.

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