Compression ring part.

[Doley68]

hello all,

I am fed up with my horrible set screws on my refractor and want to go all compression ring. The part I need is hopefully easily available but what is it called? And where is the best place to get one?

It has internal threads to fit external threads on the focuser tube.

Any help would be great!

[John]

Actually they are not easily available, not in the 2" size anyway. The only ones that I know of were made by a USA company called Mercury Systems and the model was the SFA2. Unfortunately the company has now folded and I've not found anywhere else that makes something similar

They come up very rarely used so you could watch out for one on e.bay of the UK Astro Buy & Sell website.

If you come across anyone else who makes them, please let me know - I've been looking for one for ages !.

The other option is to replace the whole focuser unit with a Skywatcher 2-speed crayford or similar - that costs around £120 I think.

There's a niche for a small engineering company here, possibly.

[Doley68]

Thanks for your reply. There was me thinking that it would be easy! Quite surprising that this little improvment would be tricky.

Have you any idea what thread it is? Is it a male T thread perhaps.

I'll have a look on the web soon & let you know how I get on.

[yeti monster]

This is how I got around the same problem:

http://stargazerslounge.com/diy-astronomer/109823-brass-compression-ring-ep-holder.html

Whilst it's a tad Heath Robinson, it certainly does the trick.

[Doley68]

Hi,

For anyone interested I have found a company who make this adaptor.

They are called scopestuff in Texas USA.

Mine is on its way. About £28 delivered.

[Moonshane]

another option is a 50mm extension tube assuming this would still allow you to focus? moonlite do a 35mm one I thin too.

[Doley68]

Funny you should say that. Tried it last week. Couldn't focus!

[AndyH]

Is it this piece here ?

ScopeStuff

Cheers,

Andy

[Doley68]

Is it this piece here ?

ScopeStuff

Cheers,

Andy

Thats it.

[spaceboy]

Hi Doley

Do you have an update? Did the item get throught customs OK or did you get stung with VAT etc?

SPACEBOY

[Doley68]

Hasn't arrived yet. Can take a couple of weeks I think.

I will let you know as soon as I have any info.

[spaceboy]

Thanks

[Doley68]

Hello all,

Well it finally arrived (over four weeks!). I was stung another £12 in total so nearly £40 all in for the part .

It is a very well made part, much better than the original. Worth £40? Not really but it is a good upgrade to the standard focusser which on my Bresser branded 6'' f8 is quite good with no noticable image shift.

In short, if your stock focusser is a good one then it is a good investment.

[spaceboy]

£40 I think I will stick with my 50p nylon thumbscrews.

I did find this Antares SCT rear cell thread to 2 inch push fitting eyepiece adaptor probably a long shot but my thinking is that this will slide in to the existing 2" focuser tube tighten down the thumb screws and hey presto a compression ring adapter???? There should only be a slight protruding of the adapter from the focuser but whether it would fit in the first place is another matter.

[Doley68]

£40 I think I will stick with my 50p nylon thumbscrews.

I did find this Antares SCT rear cell thread to 2 inch push fitting eyepiece adaptor probably a long shot but my thinking is that this will slide in to the existing 2" focuser tube tighten down the thumb screws and hey presto a compression ring adapter???? There should only be a slight protruding of the adapter from the focuser but whether it would fit in the first place is another matter.

Worth a try I would say!

[Andrew*]

If you want the ultimate system, try this: Baader 2' KlickLock Klemme M56 für Skywatcher und Celestron

Clicklock is the best locking system I've tried by a long shot, but whether it's worth €73.....

[Guest]

Hello All,

I'm also looking to replace the original draw tube adapter on my Celestron 102ED because of worries about marring my accessories. I too thought this would be easy to solve. Can anyone tell me if this adapter would do the job please,

TS Adapter vom T2 Aussen Gewinde auf 2' Steckdurchmesser

It's cheaper than the one from the States and so for that reason grabbed my attention.

I hope this thread isn't too old to revive.

Thanks

Badger

[Moonshane]

it may be possible but you'd presumably also need this first http://www.teleskop-express.de/shop/product_info.php/info/p200_Adaptor-2--to-T2---low-profile.html

the one you point to screws onto T2 threads like on an SCT.

[Moonshane]

ps, with delivery I bet it's no cheaper and you could get a used dual speed crayford with patience for <£100,

[Guest]

Thank you Moonshane,

I think that may be woth thinking about.