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View Full Version here: : 3" R&P focuser modification to 2" GSO 10:1..Thoughts?


EzyStyles
11-01-2007, 04:22 AM
Hi Guys,

As i don't have anything 3" , the new Celestron NGT-10" scope came with a 3" R&P focuser. I don't want to drill holes in the new scope as yet but wanted to still use the GSO 10:1 focuser. The screw holes were not aligned so a direct swap didn't work. After fiddling around how to mount the GSO 10:1 to the tube, I decided to use some wire tie cables. The heaviest object i will be using is the 350D which i think the wire tie cables will be strong enough.

ThoughtS?

iceman
11-01-2007, 05:37 AM
3"!? Wow I didn't know there was such a thing.

That's huge!

rmcpb
11-01-2007, 10:31 AM
You would nearly need a crane to mount your eyepieces in a 3"!!

janoskiss
11-01-2007, 10:57 AM
Cable ties! Love it. :D Now that's more up my alley than Daniel's properly machined and threaded adapters. :lol:

ving
11-01-2007, 11:04 AM
wont the cable ties leave a gap around teh edges that light can get in?

3" EPs? who has those!

Starkler
11-01-2007, 12:26 PM
Some Takahashi scope come with 4" focusers.

If the holes line up enough to get cable ties through then maybe there is enough room to get some thin bolts through the holes of both and make some largish washers to clamp it all together.

JohnG
11-01-2007, 12:45 PM
I don't see what the problem is.

Why don't you just use the 2" adapter that came with the scope and a 2" Camera Adapter, that is the maximum width opening that you can buy as standard, my Tak has 2.7" but the 2" adapter is fine for the 350D, I get no vignetting with the wide Tak T-Ring. :shrug: or a standard 2" TeleVue for that matter.

Cheers

JohnG

EzyStyles
11-01-2007, 02:42 PM
great idea geoff. hmmm i see if i have some thin bolts. hi John. The standard 2" adapter is too high to reach focus with the 350d not enough in focus plus a 10:1 focuser will be more smooth than a R&P.

EzyStyles
11-01-2007, 02:44 PM
i sealed the small gaps with black electric tap.

ving
11-01-2007, 02:49 PM
oic!

RB
11-01-2007, 03:03 PM
You're gonna love a 10:1 focuser, they're awesome.

AstroJunk
11-01-2007, 11:58 PM
That focusser is supplied with a couple of adapters to work with eyepieces.

Anyway, get drilling Eric - What's the point of collimating your scope if your focusser isn't even aligned properly! - I can hardly believe you can still by scopes with those junk r&p focussers when GSO sell crayfords so cheaply. Mine, like yours was binned for a 10:1, and I could not believe the difference!

EzyStyles
12-01-2007, 02:17 PM
i tested the focuser last night seems fine and secured without any wobbles. The 350d justttt came into focus even without the MPCC but only had about 1mm left for infocus. with the MPCC, i'll say a good 1.5cm-2cm left. i was afraid that the tube might need to be cut or move the primary mirror forward like my previous 8" f/4 scope... luckyy!