18.12.2021 And then there were two. [Shutter slides]

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 Saturday 18th 46F, leaden overcast.

I finished off the second shutter slide. Shown inverted.[Image right.] I am presently using 10mm nuts as axle spacers. To keep the skate wheels central.

Then I carried both slides out to the dome. To check alignment on the base ring [steering] track. I still have to see how to attach the new slides to the shutters.  Being solid metal the support channels can be hung from simpler brackets. Without the loss of stiffness and lack of "meat" suffered by the former softwood battens. I'd still like to include fine, height adjustment of the slides via screw threads. This may be easier with jack screws lifting the steering channel. Provided they clear the rotation roller track under the base ring.

Here is an available light image of the shutter slides resting in the steering channel. I wanted to bring out the laser level lines. These are being projected on the upper edge of the base ring all the way around the dome. 

The vertical line follows the gap between the shutters. To confirm they are vertical where they meet.

The base ring [steering] channel cannot go any further away because of the inner, shutter ribs. The channel needs to be about 20mm further out. This will allow narrow, angle brackets to be bolted directly to the shutter slide from the outer ribs. 

I rather like the clean look of the new skate wheel slides. I have more M8x60mm, A4 stainless steel bolts on order. To form the skate wheel axles. I have ordered both screws and plain shank bolts to see which is best. The M8 thread size is slightly undersized in the 8mm wheel bearings. I'm hoping that the plain shanks will be a closer fit. 

I have also ordered plain and Nyloc M8 nuts in A4 stainless steel. I can use these nuts to preload the skate wheel bearings. Both to resist tipping and to fix the centering of the wheels in their support channels. There is absolutely no point in wasting money on flashed zinc hardware. Which rusts before it is placed in the [daylight robbery] retail bubble packs. Trying to dismantle assemblies, once rusted, is a further waste of valuable time. I grew sick of rusted fixings when I was a keen cyclist.

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