Default focuser on TOA130-nfb

[zzchaozz]

Silly question, anyone has a TOA130-NFB with the default focuser?

How do you get focus on this? The drawtube is too short and most of the time, I almost hit the limit to get precise focus.

With me using NINA to autofocus, because the precise focus point is too close to the limit, sometimes it keeps asking the motor focuser to move further out. As a result, it is very hard for me to get the actual focus. Especially in a hot day like today.

[The_bluester]

I don't know about the stock focuser or fitting another one, but can you fit an extension tube between the focuser and corrector (Or camera if you are not using a flattener/reducer) That way you will get to the focus point with focuser travel to spare.

[zzchaozz]

Hmmm, this is... a good idea I think. Not sure if it works though as I need to source an extension tube from somewhere.

Hopefully, someone has the same scope as mine or has the same idea tried it out before as it is too much headache trying to pull down my setup.

[zzchaozz]

Right, I have got the backfocus wrong. The backfocus for this scope is 106.2 from the extension tube of the flattener, not from the actual flattener itself.

That means, the true backfocus is 106.2 + 25mm (of the extension tube).

That should fix the issue. I think.

[Andy01]

Both Joshua Bunn & Stefan Buda here on iis can make high quality extension tubes.
Stefan has made many tubes & spacing rings etc for my TakTOA130. :thumbsup:

[zzchaozz]

Thanks Andy, i will shoot them an PM if I really need it. And i think I would soon

[tempestwizz]

I’ve been estranged from my TOA130n with standard focuser for 12 months now due to Covid, however from memory, mine came with a fitting with a 2.7” screw thread at one end, and a 2” eyepiece fitting at the other. The distance/length between 2.7” and eyepiece ends is about 90mm. In use, I connect to a 2” diagonal into this fitting and my lenses come to focus without issue. HTH

[UniPol]

I don't recall having any issues with focus when I owned my TOA-130NFB some years ago. I just followed the systems charts which were essential.

[tempestwizz]

On further inspection of my records, my TOA130 is not a “N” version, rather, it appears to be an “S” version. The ID plate indicates only TOA130, but the Serial number includes “S” in the numbering, in my case S06045.
Research indicates the S version has the 2.7” focusing tube, while the NFB version has the 4” focuser.