Musings on a 1964 Swift 839

[A McEwan]

Hi all,

In days gone by I would have posted this on the Classics group page but as that is no longer with us, I hope that it counts as a "review" of sorts.

Through the Summer I was fancying a long-ish classic-ish refractor of some kind. Not sure why exactly - I just fancied one. So I was lucky enough to have Philj offer me his Swift 839. Made in 1964 in Japan, it came supplied with its original wooden-legged equatorial mount, eyepieces (including a few extra), finderscope and wooden packing crate.

Once received and set up, I was amazed at the good condition it was in given that it was 47 years old! The equatorial mount is beautifully enhineered - and surprisingly has no gears in it at all! The mount relies on its perfectly balanced friction to hold the scope in place while still allowing smooth motion or tracking by hand. No slow-motion controls either, so it's a bit like an EQ Dob mount for a very small thin telscope!

Now, speaking of the telescope, the optics for the Swift 839 were at that time produced by the company we now know as Takahashi! The optics in this case are 60mm aperture 810mm focal length, making it a respectable f13.5. Suitably long-ish and suitably classic-ish for my desires.

Initial examination and startesting showed that the optics were excellent, with identical intra and extra focal diffraction rings and very well controlled CA.

However, after a few weeks of ownership, I began to worry that actually using the scope would mean putting it at risk. The mount, though in lovely condition, was lighter and less firm than modern ones and I was particularly worried that I might damage it in some way, which would upset me greatly.

So... I placed an order for some Crawmach 60mm tube rings from the USA. (60mm rings are very hard to find for some reason). In the meantime, I attached a homemade Baader film solar filter and started using it to look at Sunspots. Now this is when I really realised how good the optics were. The detail and sharpness in solar white light views was amazing! It really surprised me how steady and detailed the view was. Faculae were obvious and I suspected hints of granulation! The umbra and penumbra detail was excellent and I saw a lightbridge at one point in a particularly large Sunspot.

Having been using larger refractors for solar recently (150mm and 90mm) I was surprised and pleased at how much smaller the performance gap was between this dinky little scope and the larger ones. I resolved to use it as a quick setup solar scope, and am now looking out for a 1.25" (or even 0.96"?!) Herschel wedge for it.

The other day, the rings arrived so I attached them to my modified AZ3 mount and installed the tube assembly. At the same time I dismantled the focuser as there was a little "bumpiness" that I couldn't get along with. After several dismantlings and reassemblies, I realised that there was a third "hidden" tension adjustment screw, situated BELOW the name plate on the focuser! This was screwed in all the way, so was causing a see-saw effect as the drawtube passed through. I slackened it off, replaced the nameplate, and while I was in there (purists look away now....) added some strips of super-smooth computer mouse bearing material to the glide strips. The focuser is now absolutely perfect. Not quite as good as a TeleVue r&p, but it's better than a modern Skywatcher one out of the box!

So the EQ mount is now safely packed away again and the scope will serve on the AZ3 now. The modern mount makes for a much more reassuring observing experience, and with the quality of the optics and improved focusing, it's a little winner!

Did I mention it's 47 years old?!? And thanks Phil for looking after the scope so well since you acquired it!

Ant

[philj]

Great stuff Ant glad to see the swift has gone to a good home. It never failed to impress a to just how much you can see with a good quality 60MM scope. That swift eq mount is something else isnt it, basic no frills but works a treat, i loved it despite the odd wobble.

The focuser was a wreck when i got it, someone had stripped the teeth on the pibion but thankfully the rack was still good. A dead 40mm towa gave up its pinion for the swift and that helped a lot,

That mount and the rings look good and stable i like it

Have you split them doubles yet?

Philj

[A McEwan]

Thanks Phil. Now that I feel more secure about IT being more secure (heh) it'll get used regularly. I just had a quick half hour sess with it and will take it out again after Spooks for Jupiter. Double Double cleanly split at 90x, elongated at 65x. Streetlights blocked most other interesting targets except Mizar/Alcor and Polaris - all VERY easy prey. I wonder what it will show on Jove later on...

Yep, the rings were pricey and took a long time to come - but worth the money and time in the end.

Ant

[nightfisher]

ant thats a little beauty, very nice

[A McEwan]

Thanks. I just had a very quick look at Jupiter - literally carried it out for 5 minutes between gusts of wind! Zero cooldown time, just set the mount down and popped 12.5mm Ortho in. Superbly sharp and no false colour at all. Beautiful! I really can't wait to get this to a dark site one night soon...

[JamesM]

Ant that looks like a great scope and clearly works a treat too. Congratulations on acquiring it and will look out for any further observations you make with it.

James