94 replies to this topic

[Chuck Hards]

The Vixen 36.4mm adapter has been a life-saver for many of us, easily converting many older refractors to 1.25", from the .965" size they were sold with.   

 

Let's look at it, as well as some alternatives.

 

Here is the Vixen adapter, threaded-on two different APL focusers, a Monolux and a Manon.  It fits perfectly.  Typically under $30 from North American dealers, about $15 directly from Japan but you have to wait longer.

 

 

 

 

 

 

 

 

 

 

[Chuck Hards]

The Baader 1.25" adapter works well also.  It has a fine helical focuser built-in that we don't use on refractors with star diagonals.  It has three standard setscrews with a compression band to prevent barrel marring.  About $50-$80 retail.

 

 

 

 

 

 

[Chuck Hards]

ScopeStuff sells a 1.25" adapter listed with a 36.25mm thread.  Because the older imported scopes were machined by hand, there is often enough slop in the focuser thread to accommodate the slightly different adapter thread.

 

It does NOT fit on all scopes.  

 

I like it for it's low profile.  Adds the least amount of additional drawtube length.  Too bad it's not a true 36.4mm thread.

 

  

 

[Chuck Hards]

Meridian Telescopes used to import the FOCR focuser, that used an eyepiece holder much like the ScopeStuff version, but with a longer internal 1.25" ID tube.  This makes heavier payloads less prone to tipping out-of-alignment.  I really like this one, wish I had more.

 

Same thread issues as the ScopeStuff adapter.  It fits some old ones, not all.  

 

 

 

 

[Chuck Hards]

Some older 2" focusers sold by UO used a thread-on 1.25" adapter.  On some, (not all), it was removable and can be threaded onto some older focusers.

 

 

Here installed on the Monolux:

 

 

And the Manon:

 

 

 

 

 

 

 

[Chuck Hards]

I also have used the eyepiece holder from older Chinese Meade focusers.  This one is very loose in many focusers, be very careful using it.  You need more than one thread catching to be secure.  

 

 

 

 

[Chuck Hards]

My absolute favorite, the Takahashi 1.25" eyepiece holder for 36.4mm focusers.  True compression-band tightening, unlike the Baader version, this one stays concentric as it's tightened.  Usually out of stock and the most expensive of all.

 

 

 

 

 

 

 

 

 

[Couder]

nice job of testing/listing the adapters. Also your signature is so true. At star parties, when someone asks me to look through their scope, I say "Nice view!"

[Chuck Hards]

The Vixen adapter on a Swift 831.

 

 

 

These are just a few commercial, thread-on adapters that are either in current production or banging-around in my spares box.  I've just presented the 36.4mm options that popped into my head, there must be others.

 

What have you found that works on the old imported Japanese refractors?

 

 

[Terra Nova]

See my observing report on using a 1.25” diagonal and modern eyepieces on my Mayflower 814.

 

https://www.cloudyni...day/?p=10448206

 

The benefits are amazing!

[Esso2112]

Excellent summary of options. 

[Marc-Andre]

I have a couple made by Borg;  #7314, and #7317.  Each are shown on an ATCO #1253 60mm x 910mm (Yamatar).  Both are nicely machined and finished.  I like the two thumbscrews.  They are more expensive than the Vixen.

 

 

 

 

I ordered then from;  Hutech Astronomical Products,  https://www.sciencec...prices/borg.htm

 

 

[Chuck Hards]

Nice.   I like the low profile of the 7314 especially. 

[Littlegreenman]

The Vixen 36.4mm adapter has been a life-saver for many of us, easily converting many older refractors to 1.25", from the .965" size they were sold with.   

 

Let's look at it, as well as some alternatives.

 

Here is the Vixen adapter, threaded-on two different APL focusers, a Monolux and a Manon.  It fits perfectly.  Typically under $30 from North American dealers, about $15 directly from Japan but you have to wait longer.

 

006.jpg

 

007.jpg

 

Thank you for the very informative post!

 

I want to update the current pricing on this part for Japan as found on eBay. If someone knows another source direct from Japan, please post.

Currently there are about 8 of these listed on ebay. The lowest price is $21.99, shipping included. The next lowest is $37 and change.

I have at times looked for these on eBay over many years. The pricing and availability is often in flux. Check back in 6 months and it will likely different.

In the US the Vixen importer currently sells these for $24.95 plus shipping and tax.

 

https://www.vixenopt...ories-s/116.htm

 

If I'm not in a hurry for something like this I often try a wanted ad here on CN.  

[Chuck Hards]

I last purchased the Vixen adapter from a Japanese seller in February, I paid a total of $30.38 for two.  Checking this morning, his price for one is now $19.52.  LINK   He only has one left as of this posting and is now charging $18 shipping!     Mine shipped free.  

 

Glad I grabbed those two when I did!  Looks like there is no more economy in ordering direct from Japan.  

[Marc-Andre]

Nice.   I like the low profile of the 7314 especially. 

I like that as well., and unlike Scope Stuffs, it is true 36.4 threaded.  With 2 thumbscrews, it holds EPs firmly.  The Tak looks very nice.  The only compression holder I have came with a Carton and is .965".

[Marc-Andre]

I bought the Borg 7314 and 7317 several years ago.  The prices are the same today, $31 and $35 respectively. Flat rate shipping is $4 for either, so I guess the cost is ballpark with the Vixen shipped from Japan with expedited shipping. 

 

7314 link

 

7317 link

Edited by Marc-Andre, 25 August 2020 - 07:42 AM.

[Terra Nova]

I last purchased the Vixen adapter from a Japanese seller in February, I paid a total of $30.38 for two.  Checking this morning, his price for one is now $19.52.  LINK   He only has one left as of this posting and is now charging $18 shipping!     Mine shipped free.  

 

Glad I grabbed those two when I did!  Looks like there is no more economy in ordering direct from Japan.  

I have a couple from years ago. Glad I kept them.

[Chuck Hards]

I found half a dozen Vixen adapters on the shelf when I was preparing this thread, all purchased for about fifteen bucks each.   With the price increase, I doubt that I will acquire any more.  It was king in it's day and it's still a good product, but this thread demonstrates that  there are alternatives now, some better, for about the same money.   

[Bomber Bob]

Great thread, Chuck!

 

For the poor schleps with those 30mm Astro Optical / Towa focusers (that LONG manual draw-tube + short rack&pinion section), they may want to try the upper half of a vintage 1,25" Barlow or other type accessory.  I doubt that my old Tele Vue is a unique piece of hardware...

 

 

Remove the original .965" adapter, thread in the Barlow half, and it works great.  No problem carrying my heavy Baader prism + TV eyepieces.

Edited by Bomber Bob, 25 August 2020 - 11:59 AM.

[Pete W]

Similar to BB’s solution, I’ve used camera filter step-up rings that thread onto to pullout draw tube of my Sears 6339a and Tasco 10 TE.  This then allows a 1.25” male T2 visual back to thread onto the draw tube.  This approach was first mentioned by Catboat a few years ago.

 

 

A 30mm to 42mm ring threaded onto the 6339a pullout tube, but was too small for the Tasco’s.  That needed a 30.5mm thread that then required another ring to get to the 42mm T2 thread.   Chuck’s mention that the threads often have variability explains this inconsistency on RAO scopes that are otherwise nearly identical.

 

 

[Pete W]

I bought the Borg 7314 and 7317 several years ago.  The prices are the same today, $31 and $35 respectively. Flat rate shipping is $4 for either, so I guess the cost is ballpark with the Vixen shipped from Japan with expedited shipping. 

A year or so ago I tried to get get the 7314 adapter, but couldn’t get one - my deposit was returned and it was implied that they were no longer available. I wonder if anyone’s been able to get one recently?

[Bomber Bob]

Similar to BB’s solution, I’ve used camera filter step-up rings that thread onto to pullout draw tube of my Sears 6339a and Tasco 10 TE.  This then allows a 1.25” male T2 visual back to thread onto the draw tube.  This approach was first mentioned by Catboat a few years ago.

 

F628E8FF-2114-4FFF-904F-4EDFDAD0380B.jpeg

 

A 30mm to 42mm ring threaded onto the 6339a pullout tube, but was too small for the Tasco’s.  That needed a 30.5mm thread that then required another ring to get to the 42mm T2 thread.   Chuck’s mention that the threads often have variability explains this inconsistency on RAO scopes that are otherwise nearly identical.

 

DBCCFEB0-8A9A-4DDE-855B-808800B6C467.jpeg 89BD45B6-E190-4045-A5A6-873D6AF6EC6C.jpeg

I like that solution!  Looks much "cleaner" than my long Barlow tube.  I think I tried it, but one of the rings -- probably the 30mm -- wouldn't hold, so yes!  These tubes aren't consistent on the old scopes.

[Chuck Hards]

Be careful when using step rings.  The threads are very fine and none too long.  They weren't designed for heavy loads.  I've used them all my life, have a complete range.  It's not recommended to use them for mounting masses larger than filters.

 

The idea is terrific but I would not use any "hand grenade"- sized, heavy 1.25" eyepieces or binoviewers with such a setup.  Stick with standard-sized eyepieces, and avoid knocking it on anything when carrying or using it. It can pop-off.

[Chuck Hards]

If you can find brass step-rings, they are tougher than aluminum.  I would trust them more.