which sextant?

While we're on the subject of 'Indiana Jones' sextants, I have entrusted to me a WWII Lancaster bubble sextant. It still works, after a fashion, and has tales to tell.

Now and then, when I stub my toe on it, I take it out and wonder where it's been, and what it's seen....

:)
 
Nevertheless, there's another way to look at it. The Navstar/GPS system is just man-made astro - making fixes out of two, three or more circular position lines. The 'Murricain electric stars' up there don't last that long - half the bleedin' things are knackered now after only 15 years. As for the twee wee receivers, I've got four. Again, maybe half of them are working....

Now, the original, genuine, 'does what it says on the tin' stars 'n planets. They've been working away up there for us, stuck onto the inside of the Celestial Sphere, without a day's 'downtime, off-line for maintenance or obscure reported unreliability for yonks. Millions of yonks, actually. And they'll be there, insh'allah, long after thee 'n me have gone. Reliable or what?

Arf! Arf!

Why does the sun come up?
Or are the stars just pinholes in the curtain of night?
Who knows?
 
I think there is a lot of snobbism about sextants. I own both kinds (RN metal from 1942 and Davis Mark III plastic). I don't know how to use them yet (although I plan to learn).
If the only reason the OP wants to buy one is to get through YM Ocean, I wonder whether it is sensible to spend hundreds. I would have thought a plastic one will let you learn the principles, and get through the course. If you want to buy one for the beauty and form, or because you intend to do a lot of astro nav, then by all means spend hundreds. But I think you might be wiser to spend less for something that you are likely to use only for a very short period of time, that is never likely to see the light of day again.
 
I'm in the same boat (groan) and have been keeping an eye on ebay for a few weeks.

There are loads of soviet era SNO-T (also known as CHO-T) sextants, some from India and some from Eastern Europe. The prices on the Indian ones tend to be better (typically $300 to $400) but as already mentioned in the thread, it is hard to tell their functionality. The ebay CNO-T sextants have shot up in price since the quality of these sextants has become known amongst navigators. A good one compares well with the best on offer from Tamaya and C&P.

There are a few Tamayas, relatively old and not current models. These typically go for more than the SNO-T. Every now and then a Spica appears and these fetch about $600 or more.

The Astra IIIBs largely go for silly money - you can pick up a brand new one for a similar price. If this sextant grabs your interest, the RYA have a fantastic deal for members.

I fear the days of grabbing a quality sextant for a hundred quid have gone, but I'm still looking (and I'd probably pay more).
 
I decided out of pure interest to learn to use a sextant. I considered a Davis plastic job, but wanted something I could take pride in. I looked at ebay, but not all said, "for display purposes only! or "not for navigation", though some clearly were replicas for ornamental purposes - too much chance of buying a pig in a poke. At the end of the day, I went for an (new) Astra 3B - a proper metal sextant at a price I wouldn't lose sleep over.

On the other hand, I wanted to learn astro navigation from first principles (just for the mental exercise!), and bought "Astro Navigation made Easy", by Francois Meyrier. I think I need to find another book; this one contains equations in which the terms are not defined - not how I learned maths when I were a lad!
 
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In the OP's position I'd buy a cheap plastic sextant first and start learning on that. If the compulsion to navigate by astro continues undiminished then he can buy a good metal sextant with the benefit of knowing what he's looking for and having the skill to check that it works.
I've heard of a couple of people that have bought metal sextants that they subsequently discovered had been dropped and ruined forever.
 
which sextent

the cheapest plasy one is best you will never use it nowadays with gps around since about 1985 tables cost more than a gps
i must admit i now dont carry a sextent when ocean going
i self tought before gps from exelent book celestial navigation by mary bluet
not sure of spellings but do a google search for this book
pps early navigators had niether and they got by, and watch you dont fall of the edge
enjoy your course:)
 
I think I need to find another book; this one contains equations in which the terms are not defined - not how I learned maths when I were a lad!

Try Tom Cunliffe's 'Celestial Navigation' - Amazon or any of the chandlery bookstores. Concise, to the point, explains what you need to know. That and the Reeds tables will get you there with the minimum of fuss and with satisfying comprehension to boot.
 
Ebbcos fine for actual navigation, as long as you check index error before and after each sight, which is a bit of a pain but do-able. Have used one to genuinely navigate in earlier poor days. Many years later dug it out prior to a long passage and went out and bought a 1941 ex-US Navy sextant, which had much better optics for my by then much older eyes. Bought it in a Hong Kong chart agents.

I would not buy a metal sextant without looking and handling it first, the arm needs to swing smoothly, and the teeth into which the micrometer engages need to be "ungraunched". Most other errors can be adjusted out, and at worst mirrors can be resilvered.

I once tried using someone else's mini Zeiss 'yacht sextant', lovely piece of engineering but it seemed too small and light after a full size one.

Do the YM Ocean with a plastic one, and once you can achieve position lines within a mile or two with it, you'll know enough to look at metal ones, which are nice toys to play with.
 
Re BilboB,
Don't want to put a dampener on things but I had a bad experience buying a s/h Tamaya from India on Ebay--In fact got into the usual slanging/feedback/complaints ignored routine that sometimes happens on Ebay.. THE SELLER was pretending to be in California, a marine expert, in fact I reckon he was Del Trotters long lost Indian cousin Slippery Sammy..

Otoh I have a really nice, easy to use East German jobby from an Ebay yotty which is an absolute joy to use ( very occasionally).. Oh yeah and the obligatory plastic Ebbco.


To the Original Poster.. The Ebbco took me to the canaries some time ago just fine-but trying to pinpoint the Cap Verdes with hazy rubbish visibility was pretty useless. Not really the fault of the sextant, that.
 
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