Which T ring adapter? 😩

[CaptainShiznit]

So I have this T ring: https://www.firstlightoptics.com/adapters/t-rings.html

Someone on one of my earlier posts said that I didn't require an adapter for this. At first I thought he was right and it fit into one of the eyepiece tubes that came with my 130PDS but it doesn't.

So I bought this 2" adapter: https://www.firstlightoptics.com/adapters/flo_2-inch_T_adapter.html

While this fits into my 2" eyepiece, the T ring is too large. What have I missed?

 

T-ring and adapter:

 

1.25" and 2" eyepiece tubes:

 

1.25" eyepiece tube separates into 2 parts (at first I thought this was how I was meant to connect it but the thread isn't right)

[Waldemar]

Two types of thread are used with these adapters: T-2 which is M42 x 0,75 and used for 1,25" nosepieces and M48 also called 2" which is M48 x 0,75 and used for 2" nosepieces. Some Chinese  producers cut them M48 x 1 and those will not fit. Maybe you got one of those, I encountered that too some years ago, very frustrating... That may also have happened with the EOS adapter, though I've never seen that.

Best way to solve this is to contact a fellow astronomer or club, or a local astronomy store.

edit:  B.t.w. M-36 x 0,75 is used as well sometimes. Maybe you have a caliper to do some measuring? 

Edited January 17, 2020 by Waldemar

[CaptainShiznit]

17 minutes ago, Waldemar said:

Two types of thread are used with these adapters: T-2 which is M42 x 0,75 and used for 1,25" nosepieces and M48 also called 2" which is M48 x 0,75 and used for 2" nosepieces. Some Chinese  producers cut them M48 x 1 and those will not fit. Maybe you got one of those, I encountered that too some years ago, very frustrating... That may also have happened with the EOS adapter, though I've never seen that.

Best way to solve this is to contact a fellow astronomer or club, or a local astronomy store.

edit:  B.t.w. M-36 x 0,75 is used as well sometimes. Maybe you have a caliper to do some measuring? 

Thanks for the help. I've been in touch with FLO who were very helpful as usual.

When I first got my scope, I fixed my camera to the 1.25" eyepiece tube that comes apart in my picture above. When I went to actually use the scope, I found the camera didn't fit and thought I was going mad.

The inner ring of the T ring had detached and stayed inside the eyepiece tube (which was the first thing FLO advised I check).

I now need to find a tiny allan key to tighten the inner ring back into place!

[Louis D]

The reason the two rings are separate is to allow for camera angle adjustment.  It was more important with T2 camera lenses back in the day.  Now, you just loosen the focuser tube lock screw(s) and rotate the 1.25" or 2" adapter and tighten it back up.

[CaptainShiznit]

1 hour ago, Louis D said:

The reason the two rings are separate is to allow for camera angle adjustment.  It was more important with T2 camera lenses back in the day.  Now, you just loosen the focuser tube lock screw(s) and rotate the 1.25" or 2" adapter and tighten it back up.

I see, I was wondering why they were separate. The problem I have now is the grub screws that hold the inner ring inside the main T ring are loose and the tightest I can get them with my smallest screwdriver still allows the internal ring to move. They look like Allan key types so I'll have to find a small key to tighten them up.

[Waldemar]

In the future you might need other sizes Allan keys… maybe wise to buy a set, they are not too expensive.
be aware two types are available... imperial and metric: https://www.amazon.com/imperial-hex-key-set/s?k=imperial+hex+key+set
Most of the time these rings use metric sizes.

[Geoff Lister]

I managed to get a set of small Allen keys for a quid at my local "Pound Shop".

Geoff

[CaptainShiznit]

Thanks guys. I've already picked up a big set on Amazon on their way today. Great minds

[CaptainShiznit]

Just in case anyone has the same question and finds this thread, the grub screws in the astro essentials T ring are size M1.5

[Louis D]

On 18/01/2020 at 02:57, Geoff Lister said:

I managed to get a set of small Allen keys for a quid at my local "Pound Shop".

Geoff

Off topic, but I put it here because I had to think for an extra second what a quid and a pound shop were.

I literally couldn't find a single online translator that could handle this UK to US conversion.  My best would be:

I managed to get a set of small hex keys for a buck at my local dollar store.

OR

I managed to get a set of small Allen wrenches for a buck at my local dollar store.

At first, I was like, why is he using squid for money and second, why did he go to an animal rescue to find hardware?

Two countries separated by a common language.

[CaptainShiznit]

45 minutes ago, Louis D said:

At first, I was like, why is he using squid for money and second, why did he go to an animal rescue to find hardware?.

I have no idea if it's national, regional or some quirky thing I've only heard a handful of times but you've stumbled close to what is slang for £6. An ill octopus (sick squid).

[Waldemar]

sick squid for 6 ponds?  so six quid… 🤣