Quote:
Originally Posted by strongmanmike
Sounds like you have it covered and I saw the raised section on your Dream tube too, nice idea, I think the thicker core of the Dream tubes means this should be adequate to stop tube flex with a heavy camera and filterwheel..?
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Yes, I believe the Dream tubes are excellent quality and rock solid. They are made with thick cores, the resin/CF weight ratio is about 35% (critical for stiffness) and they use high temp epoxy resins baked in curing ovens. The focuser platform is then bonded on and it too is then post-baked on the tube. Dream has testimonials from a customer using their f/3.5 16" astrograph stating that focus did not change over an entire night even with temperature dropping a reasonable amount.
My current home made 200mm scope tube that I personally made is a hand layup / room temp epoxy / standard eglass (ie. not CF) with a 6mm honeycomb core, but even it is very strong. I can stand on the end of the tube (80kg) with little flexure (may be a pic on my website). It has reasonable thermal properties judging by the fact that I have very little focus shift ovr the course of a night.
Quote:
Originally Posted by strongmanmike
Delivery is still waiting on the Atlas focuser to be built and sent to the UK
My AG12 will have the complete tube ring brace option fitted as per the attached photo, this is a similar solution to Wolfgang Prompers ASA 12 . I am also having a custom CF light/dew shield made that rigidly attaches (to hold a light box if required) but is removable, integrated secondary and tube heaters controlled via a rear mounted controller and Ultra grade optics upgrade (just cause  ). |
Looks very good Mike - that should give you a stable base for your focuser. I plan on making a light/dew shield as well for my scope. I'm not sure what you mean about it holding a light box? Do you mean a light trap? I built one into my current 200mm scope tube - but they go opposite the focuser to prevent reflections from the opposite wall.
Anyway, I'm going to IISAC this Thursday - if you're there we can have a chat about our scopes
