Thread: 10" F4 build
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Old 07-01-2013, 03:50 PM
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alistairsam
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Join Date: Nov 2009
Location: Box Hill North, Vic
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Its been a few months, but I finally finished my 10" F4 serrurrier truss with CF tubes. I went with woven 1mm x 16mm CF tubes rather than pultruded as they were half the weight of the pultruded, 72g for a 1metre x 16mm OD tube.

I've tested collimation with a cats eye AC and its holding well at different orientations, there still is some flex but very minor.

The guitar string spider is working a treat, hardly any spikes and very rigid.
I need to get a proper shroud done though.

All up, the OTA weighs 11.5Kg with a QHY8 ccd and the guidescope/guidecamera and my dew heater box.
I plan to replace the wooden dowels in the UTA with CF as well, so should end up at 11kg.

The truss nodes are terminated on Aluminium elbow joints which is basically two U channels inserted into each other so they are free to swivel to the required angle.
The Octagonal shape causes the trusses to form a cone which is what I wanted as that has better rigidity than the cylindrical truss configuration.

I used a 1inch long 16mm wooden dowel as the CF tube insert to connect to the Aluminium elbow joint, but since the standard size is 16mm OD, and the CF tube ID is 14mm, I had to convert my drill press to a wood lathe to turn it down to 13.5mm. I then used the 6minute Epoxy glue available from hobby shops to glue it inside the CF tube. They're only 1 inch long so doesn't add up too much weight.

I also got a belkin 4 port powered hub which supports the qhy8, qhy5 and canon1000d. I finally have no more USB issues after changing about 3 different hubs.

My HEQ5 pro seems to handle it okay, but i'm guessing its borderline for this mount.

still, I'm happy with the way its turned out. comments, suggestions, welcome.
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