Mk II Dobsonian 16" f5 truss tube

Truss tube

The 25mm tubes are all the same length. There are four left-handed and four fight-handed ones. The top fitting is straight out of K&B and seems to be used on 12.5" Obsessions:

The bottom fitting is also from K&B, with the clamp and stop screw fixed to the channel, and the whole thing bolted to the mirror box with just one M6 bolt:

The whole tube is extremely rigid when assembled. Just as rigid as Mk I.

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