Swapping out standard focuser for DS

[Hitman77]

Hi folks. This may be a daft question so I'm hoping some of you have had a similar issue and can help me resolve it. 

I recently swapped out my standard Skywatcher focuser on my 12" Truss Dob to a duel speed Skywatcher focuser. First opportunity to use it came last night where I noticed the 2" adapter does not fit into the focus tube. It worked great with the single speed but is unusable at the moment. I popoed the 2" straight into the focuser sans adapter but obviousley could not resolve stars due to too little back focus.

Is there a standard bit of kit I need to buy? Had a look online but wasn't really sure what I was looking for? 

Any and all suggestions gratefully received

Andy

[Moonshane]

Sometimes the 2" adapter has a different diameter to the focuser drawtune - to check this, confirm whether or not your 2" eyepieces will fit into the old focuser without the adapter. Not focus, just fit - do this in the hand.

I presume it won't. Also assuming it's 50mm in length you want a 50mm extension tube maybe like this one (there are lots available). http://www.ebay.co.uk/itm/Revelation-50mm-Extension-Tube-2-/272335726370?_trksid=p2141725.m3641.l6368

you may also find that you need a 2-1.25" adapter although your new focuser may well have one.

[Hitman77]

Thanks for that Moonshane - and the link

[bomberbaz]

Iused a 35mm ext tube in my 12" flextube but cant remember who made it. It was self cetreing too.  

[Hitman77]

What does "self centering" mean BomberBaz

[bomberbaz]

On 6 September 2016 at 18:38, Hitman77 said:

What does "self centering" mean BomberBaz

During tightening onto the eyepiece its mechanism ensures the light path goes through the centre of tge eyepiece.