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Re: Newtonian Tweaks And Tips

PostPosted: Sat Feb 18, 2012 12:11 pm
by PARTY MARTY
Thanks Dion for the info! ;)

I'll give you the dimensions of my 8" Quattro, once I'm back from OP Tour within 2 months time, so I'll give you a buzz mate?

Re: Newtonian Tweaks And Tips

PostPosted: Sat Feb 18, 2012 12:50 pm
by Dion
No worries ;)

Re: Newtonian Tweaks And Tips

PostPosted: Sun Feb 19, 2012 3:16 pm
by Malamuteboy
A good Video as usual. The collimation for the focuser is a pain with the obscured screws underneath the focus wheel assembly. It's the same on the 300 PDS. I ended up grinding a couple of Allen keys down.

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It's good to see that Skywatcher a making improvements. My 300 only has the usual 3 clips holding the mirror.

Re: Newtonian Tweaks And Tips

PostPosted: Sun Feb 19, 2012 9:35 pm
by SteveG4iwr
Great video Dion and I hope you don't have to wait too long for the new secondary. I would have been chewing lumps out of the kitchen table after all of the care you had taken.

Newtonian Tweaks And Tips

PostPosted: Sun Apr 01, 2012 9:42 am
by teslar
Quick question on flocking Dion. Did you just flock up to the ridges from either end. Or did you go all the way through.

I felt your pain there with the secondary. Very good of you to show that it's a salutary lesson to us all. I hope they come through with a replacement soon


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Re: Newtonian Tweaks And Tips

PostPosted: Sun Apr 01, 2012 10:08 am
by Dion
Hi Tom, I just flocked up to the baffles on each end, but depending on your tube allowing, sometimes you can flock right up to the edge and the ends still fit ok, albeit a bit snugly, sometimes you need just draw a line round the inside of the tube where the ends blt on and flock up to it. On the CF model i recommend going up to a line as the mirror cell and front cap end up too tight a fit and you could split the carbon tube, on a steel tube you obviously have a bit more 'give'. On my 200P I did right up to the edges of the tube. If you have one of these they're really handy for cutting flocking nice and straight/accurate :-

http://www.ebay.co.uk/itm/Cathedral-A3- ... 926wt_1396

Re: Newtonian Tweaks And Tips

PostPosted: Sat Apr 14, 2012 3:54 am
by Barfbagger
Dion, I'm interested to know why you had to cut the bracket for the Skywatcher electric focuser. Following your recommendation I bought one for my 300PDS and managed to install it with 4 screws holding it in place. I must admit the instructions were useless and I was looking at a botched job trying to install the flexible drive shaft adapter which I later discovered that I didn't need.

First of all I removed the bottom plate and turned the focuser round so that the motor could be fitted on the other side. The problem was how to tighten the grub screws that clamped the motor to the focuser shaft as the holes didn't align with the screw heads. I eventually realised that if I removed both of the dual speed focussing knobs, then the shaft could be slid into a position where the grub screws were accessible. Once that was done the unit could be reassembled and bracket lined up perfectly. My only gripes are that the four long replacement screws are cross-head instead of hex-socket and the washers holding the motor to the bracket need spring washers to prevent them loosening.

Re: Newtonian Tweaks And Tips

PostPosted: Sat Apr 14, 2012 10:10 am
by Dion
That's because there are several different focuser models used in skywatcher scopes, generally they fit the standard skywatcher crayfords fine, but from the DS models upwards, the screws are in different positions, the quattro focuser is a completely different design again and even has two focuser locks.

Re: Newtonian Tweaks And Tips

PostPosted: Sat Apr 14, 2012 11:09 am
by Barfbagger
How do you find the Quattro focuser compared to your previous one? Do you find a big difference when using the motor?

Re: Newtonian Tweaks And Tips

PostPosted: Sat Apr 14, 2012 1:11 pm
by Dion
the quattro focuser is a very different beast than the standard Skywatcher DS types, it has twice the number of ball races in it and the actual focuser plate, the 'pinion' if you like even though it's flat, actually has grooves in it's edges because that also runs within a set of sprung ball bearings. The two focus locks also allow if you like a 'balanced' lock, as you can imagine, a single locking screw will actually push the focuser tube out of square in effect which will adjust the focuser collimation.

As an aside i have a video planned which may make some people realise how much play there is even in a DS focuser and how you can use it to your advantage.