Polarex 80mm spotting scope

[Trevor PC]

Good day to you.

I have just bought a Polarex 80mm spotting scope for £20 to use as a travel scope as my Tal 1 is to big to take away with me.

I read allot about them and watched the you tube  video  by Dave where he unscrewed the turret to put a star diagonal on it, which I liked the idea of as I could buy a hybrid diagonal so I could use 1.25" eyepieces.

Then the problem,  mine seams well and truly stuck on, and won't move.

My question is does anyone know if they were actually glued on, or I am missing a trick.

Secondly if any one has one will I be able to change the 0.965 eyepieces for orthoscopics,  as the reviews I have read mention the ones on the turret are not great?

As it was only £20 I plan to repaint it and lube some of the parts that need it, so any maintenance tips would be useful.

It didn't come with a box so plan to make one so  any help with dimensions would be helpful 

Any guidance would be much appreciated.

[Mr Spock]

I don't know anything about the scope but you can get 0.965" eyepieces used. ENS Optical always have a few for sale, though, each will cost more than your scope!

[Trevor PC]

I will try them, thanks for the information.

[DaveL59]

I found the on a web search, interesting little scope tho he reports optical aberrations from likely pinched optics and he's since heavily mod'd it

Polarex 80mm spotting scope (skysurfer.eu)

Doesn't show how he removed the original turret tho.

There's also a few posts on CN on the Polarex and Unitron versions, hard to know what to suggest as its always possible a previous owner has used glue or threadlock to secure parts. Any sign of small set screws around the securing ring at all as that's another possibility.

Some pics of it might help 🙂 

[Trevor PC]

Hi 

The you tube video of the Unitron 80mm spotting scope has an additional threaded part that Dave undid to remove the turret the Polarex version does not have this, have looked at the threads and at the end of one of them  Starman gives the impression that it is glued, and that's where the thread ends.

As an ex engineer it seems strange that Unitron went to the trouble of making different versions for the American and European marks maybe a cost thing. 

Will add some pictures when I have finished the ironing, oh isn't retirement a wonderful thing.

Thanks for your help.

Trevor 

 

 

 

 

 

 

[Trevor PC]

Hi 

Some photos to help the discussion.

 

[Trevor PC]

[DaveL59]

Nice looking scope there 🙂 

There does look to be some corrosion where the turret meets the collar which could freeze the threads making it hard to remove. I'm guessing that silver tube the turret screws into is the drawtube for the focuser and the silver collar is part of the focuser and nothing to do with the turret. Looks like the turret screws into that silver tube, or perhaps is a push fit. 

You could try extending the focuser outward then use a hairdryer to heat up the area next to the turret and then try again to unscrew it. That may soften any glue in there or help break any corrosion bond. Remove the eyepieces from the turret first too, just in case. I'm loath to suggest using a penetrating oil since if you can't fully dismantle then it'd be a pain to try clean it all away but if you suspect glue then nail varnish remover may help. Just be careful using that and heat and of course usual precautions when handling heated metal too 😉 

[Trevor PC]

Thanks Dave 

I have taken the turret off by removing the small screws from the back plate, once removed all you are left with is a circular disk that fits inside a recess on the turret , the one on you tube reviewed by Dave Trott  has a small stub shaft still attached to the turret when removed from the focuser by undoing a threaded ring.

The focuser has some marks from I presume was dried grease.

When i got home from picking it up the focuser was stuck, fully wound in, and it was a struggle to get it to move out.

I am starting to think that maybe what I can see on where the fucuser joins the plate the turret fixes on to is a result of this.

At the moment I am not sure what to do so have contacted the Unitron history website to see if I can post a question there.

Will keep you posted on my progress.

 In regards to eyepieces they are 0.965" with an external screw thread, that allows them to be  screwed in to the turret body and locked into position by a locking ring that is shown in the photo I already attached, my question is have you ever seen any other eyepieces like this?

Many thanks for your support.

Trevor 

 

 

 

 

 

[DaveL59]

10 minutes ago, Trevor PC said:

 

 In regards to eyepieces they are 0.965" with an external screw thread, that allows them to be  screwed in to the turret body and locked into position by a locking ring that is shown in the photo I already attached, my question is have you ever seen any other eyepieces like this?

Many thanks for your support.

Trevor .

 

that's great news, yeah dried grease can be a real pain on vintage gear unfortunately.

Not seen that type of eyepiece before to be honest, likely specific to that model line or other spotting scopes of that type?

I wonder if the barrel on the eyepiece can be cross-fitted to a star diagonal so it can be securely mounted if you go that route. I noticed on the youtube vid that he slipped the diagonal in rather than screwed it so I assume not. Made me think a solution would be needed to hold the diagonal secure in use else it hits the deck in the dark when you east expect it.

[Trevor PC]

Dave 

The  way he used the diagonal  made me think of possible accidents.

I have done some terrestrial viewing an it looked OK not great, but for what I plan to use it for it should be alright for some basic star gazing and for looking at the moon when I am on holiday, and when I am being lazy and not using the Tal 1.

Be interesting to see what the American website has to say!

Any idea if I should be using any grease at all on the focuser, and if yes do you know what type?

Regards

Trevor 

 

 

 

 

[DaveL59]

I'd guess that being a metal assembly that some grease, a smidge, would be good to gain a smooth action, but what is the underlying mechanism?

If its a helicoid then a good synthetic damping grease would work, I use this on camera lenses, basically pick the thickness based on the coarsness of the thread you plan to use it on:

Helicoid Grease -6x15ml Complete Bundle- for Camera Lens Focus Ring Optical Lube | eBay

I guess you could also use superlube but typically you'd want some drag or the focuser would feel pretty slack.

PS - you can but the individual grease can rather than an entire set, just do a search on the bay-of-e 😉 After all £90 for a full set for a single item being repaired is a bit much. 

Edited June 21, 2022 by DaveL59

[Louis D]

If it wasn't near optics, I'd recommend CRC 5-56 penetrating oil to loosen those corroded threads.  I've used it successfully to loosen fully rusted bolts inside my gas grill after soaking for a day.

[Trevor PC]

Hi Louis 

Thanks for the information, I took the turret off and the plate that it screw to does not appear t of be threaded, but in one piece.

I must have one  that is  really odd/rare, will add some photos so you can see what I mean.

Regards 

Tevor

 

 

 

[DaveL59]

Hi Trevor

I'd suggest that the turret nosepiece is likely either a push fit or screws in and possible is secured with some thread locking adhesive. Third photo does show what looks to be a join where the turret meets the drawtube, hence my thinking. Some heat might help get it to free up, hairdryer better than a blowtorch but if you do try the latter get a micro-flame type and shield the rubber grip of the focuser so you don't melt it. You might even find that a stint in the freezer would help but bag the scope up and put a dessicant pad in the bag first.

If you have access to a pin wrench, those 2 holes in the turret backplate left on the scope could help you apply leverage, just use reasonable force rather than lots so as not to damage other parts of the focuser mechanism 🙂 

Edited June 24, 2022 by DaveL59

[Trevor PC]

Hi Dave good to here from you, as an ex mechanical engineer I had a close look at the back plate for the turret and on its inside there is no sign of ia screw thread or a pressed on focus tube. The two holes you mention are threaded to hold the spring plate that holds the prism in place. 

I think I am missing a trick somewhere on how to remove the focuser. 

The other area is how to remove the main lense for cleaning with the due shield on. 

Why oh why did Uniton make different versions from the one shown in Dave Trott's video on YouTube. 

My only other thought being did Unitron make a military version? 

It's hard to believe that no one across multiple astronomy forums has one of these.

Still hoping for someone to contact me about this type failing that it will be a limited refurb and live with what I have and use it for low level star gazing. 

Again as always thank you for help. 

 

Regards 

 

Trevor 

 

 

 

 

[Trevor PC]

Dave

Out of frustration just bought a pair of vintage binoculars for general star gazing, made me feel some what better. Don't no what my other half will say if the arrive when she is home I hate to think, us men and our hobbies. 

Stay safe as I just got pinged for a covid proximity warning which was from a trip to the astronomy  club talk on volcanic action on the moon about 2.5 to 3 billion years ago, is no where safe from this virus.

Regards 

 

Trevor 

 

[DaveL59]

Ahh I hear you on the frustrations when trying to dismantle, I've a Hensoldt Wetzlar Jagd Dialyt that I can't get the objectives out as the lens rings won't budge. Likely alloy corrosion has locked them into place and short of a mini-flame torch I'll never shift the rings. Annoying as the lenses rattle slightly, so I used black sealing wax to set the lenses so they no longer rattle. Hell of a cheat but you don't see the wax around the rim and it's worked just fine. Cleaning the inner side of those objectives was run too being 3 inches down a tube.

Vintage bino's are often good tho collimation and wear from age may need addressing. They're not usually weatherproof either. I tend to use a pair of Minolta 10x50's for night viewing, which I picked up at a great price (£26 IIRC) and they're multi-coated, rubber cased and weatherproof.

Yikes re the prox warning but not unexpected these days in any space that has a good number of people. Surprising (more) that folks are still running the NHS apps, I expect many have turned those off or deleted now that "it's all over so we're safe...", so far I've not had any alerts but I tend not to be in crowded spaces too often.

[Trevor PC]

Well I bought a pair of 10x50 Swift Newport Mk 2's off eBay, for tripod use should I hope be Ok for a bit of star gazing.

Did think about a pair of 20x80's any thoughts on this size and have you ever used very large binoculars.

As always many thanks.

 

Trevor 

 

 

 

 

[DaveL59]

3 minutes ago, Trevor PC said:

Well I bought a pair of 10x50 Swift Newport Mk 2's off eBay, for tripod use should I hope be Ok for a bit of star gazing.

Did think about a pair of 20x80's any thoughts on this size and have you ever used very large binoculars.

As always many thanks.

 

Trevor 

 

 

 

 

Ahh Swifts are generally pretty good and have a handy tripod mount. I did consider getting a pair of large Swift 20x in the past but never did as I couldn't see them getting much use being they aren't fitted with angled eyepieces, neck ache becomes a problem as well as needing a tripod/monopod that can be used high enough to support them in use. Not exactly hand holdable those big Swift bins.

I do have a 15x50 pair of japanese bins that are of the skeleton/micro style which work quite well (far right in the pic)

I've a bit of a collection of these types ranging from 5/6x up to the 15x as well as a number of other regular ZCF and DCF roof models 🙂 

[Franklin]

23 minutes ago, Trevor PC said:

Did think about a pair of 20x80's any thoughts on this size and have you ever used very large binoculars.

I've got a pair of 20x80's, they're Vixen Type-B and are optically very nice. I use them hand-held for scanning around but not for long, they really need to be tripod mounted to get the best from them.

[Trevor PC]

Dave. 

A great collection of bins, what are your favourites, and what are angled eyepieces, you will have to excuse my lack of knowledge.

Regards

Trevor 

 

 

[Trevor PC]

Hi Franklin 

Thanks for responding have no heard of the Vixen binoculars you have what attracted you to them, I can imagine they are quite rare.

 Again thanks.

Trevor 

 

 

 

[DaveL59]

I've so many but my faves to use are probably:
Nikon Micron M CF 7x15 which are easily pocketted and generally live in my camera bag
Hensoldt Jagd 6x42 Dialyt which give easy relaxed views
Nikon Sportstar EX 8x25
Copitar 8x20 (compact reverse porro, think there's a  minolta version of this also)
Foton 7x35 (nice solid russian bin)
Chinon 10x40 
Swift Audubon HR/5 8.5x44 (also have a MKii of these)
Minolta Classic Sport WP 10x50
 

All these are regular straight-thru designs, after all they're aimed at ground level observing in the main. Ones with angled eyepieces allow you to look down into the bino so when viewing at altitude objects you aren't cranking your neck back, much the same as using a telescope with a diagonal rather than straight, just more comfortable. Binos like this are likely more aimed at sky observation which tends to be large and expensive specialist gear for the like of us stargazers.

[Louis D]

11 hours ago, Trevor PC said:

what are angled eyepieces?

45 degree bins:

 

90 degree bins: