Which Sextant

I have a Davis mk 15. It's the only sextant I have extensive experience with so take any comparative statements with a pinch of salt. BelleSerene's comment about the 25 vs the 15 make sense. I adjust my sextant every time I use it but it only takes a minute, some of which you'd spend anyway *checking* it. I've read comments on previous threads about plastic sextants where people say "yeah they're good enough for sun sights but you can't do stars". Nonsense. The Davis is fine for stars.

If, rather than keeping your sextant on your boat, you're intending taking it on other people's boats where one leg is a flight you'll appreciate the lesser dent the davis makes in your baggage allowance. They're obviously lighter and I've heard people say this makes them easier tools to use for measuring angles in coastal navigation, but to my shame I can't actually remember the last time I calculated distance off from the height of something.

Note that sextants seem to be substantially cheaper in the US (where I bought mine) than the UK if you have occasion to travel there (especially to a state with negligible taxes)

Since getting my own boat I have been tempted to buy a "good" sextant, for comparison if nothing else, but I haven't got round to really doing the research to decide what I want
 
An Ebbco plastic sextant did the job for me for 4 years around the Atlantic.

I did enjoy getting away from all the faff and uncertainty when I got my first GPS>

You can find Ebbco sextants on Ebay for about 10 quid. I got my current one from a dumpster in St Lucia after the ARC. Nice box.
 
Plath was probably the best I ever used. Tammaya Spica or Jupiter are excellent. If you can find one for sale used at a reasonable price. For the kind of money they are worth. Get it from a reputable instrument dealer. A good one is worth a lot of money. It is not possible to have a Zero Index Error. I have used Tamama, which were set up by an instrument maker and I couldn't measure an index error. Or I measured it as Zero because it was so small I couldn't detect it.

Unfortunately there is not many instrument dealers around now. Kelvin Hughes closed there outlet in Glasgow long ago.

I always regretted not buying my own. Back when I actually used them regularly. It was probably wise they don't travel well. We always had good ones on board.

Nostalgia, My own boat and the desire to have the ability to show a youngster how to use one. I decided to get my own. I don't have a real practical use for one any more.

I had a bad experience with Ebay. I bought a Tammaya on Ebay. From an English dealer. I think the Indian ship breakers are more honest. The Sextant had been dropped and the casting broken and stuck together with black electrical tape.

Back in the day. My personal favourite was an East German Zeiss. If I could find one I would by in a heartbeat.

Friebergere is basically the same company. I think the Frieberger is a bit smaller and lighter than the original Ziess. East Germany was still East Germany back in my day. I think Kelvin Hughes used to sell both a ship Ziess and the Yacht Zeiss.

My Sextant is a very nice Frieberger, originally marketed as a yacht sextant. The micrometer drum is only graduated to 1'. It was a good Ebay experience. I bought it from a sailor. If Saraband has one for sale. By it. I paid 450 Dollars for mine. I use it every year to show someone how. If you don't by it I might. Having two good sextants for demonstration would work for me.

I have used a Davis. I personally would not spend a dime on a used Mark 15 or 20. This may offend Davis owners, who swear by theirs. lots of people say they get good results with a Davis. I have had acceptable results with one and quite like to use one as a teaching aid. But I tend to swear at the Davis. Having used a good quality metal Sextant. I just find them frustrating to use. Its not just the re adjusting. Its the optics. The weight, the feel.

I would like to find Davis Mk 3. Its designed as a emergency use sextant for USN. Not adjustable and very simple. The USN tested them and finds them much more reliable than any other plastic sextant.

I've never used an Astra, looks like a Chinese knock off of a Tammaya. Probably Just about as good as a Tammaya. For a very reasonable price. The Astra appears to be a very good sextant. Best value for money is a new Astra. When I looked it was about twice the price of a new Davis.

If you get a good sextant, you will not loose out, A good one will go up in value. You will always be able to sell it again.
 
I have a Plath which has been in the family for 68 years, I also have a 1981 Freiberger Trommel-sextant ( ie Drum) that I bought off a sailor a few years ago. And last but not least I have an Inglis Smith yacht sextant with a frame about half the size of the other two. Japanese made and rebadged in limited numbers for a Victorian chandlery in about 1970.

We can ignore the latter as its the only one of them I have ever seen. Its optics are nothing flash.

The other two? On both the drum is simply calibrated to the nearest minute but its easy enough to read off to 1/10' just by inspection.

Optically the Freiberger has the brighter image of the two and slightly higher magnification. No surprise there as they were made by Carl Zeiss, Jena, who also made some of the best binoculars out there.

I've handled Tamayas and always found them very heavy compared with the Freiberger... which is a major consideration if you are taking stars. If the Astra is a Tamaya clone they may be the same weight.

My choice would be the Freiberger.

There is a seller on Ebay who seems to have cornered the market in 'as new' sextants coming off ships being broken up in India... I imagine he would be safe enough to deal with as I don't think anyone has got into the replica Freiberger market yet.

Some may find this of interest... the magazine only paid for 'first publication rights' so mine to do with as I wish ... written about 25 years ago..

https://www.dropbox.com/s/oxduof5rsz8zwtb/Offshore Navigation.pdf?dl=0
 
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Back when GPS meant Gray plastic sextant , I used a plastic ebco micrometer sextant for several Pacific crossings .No problems, no complaints.
The shades and mirrors have screwed up, but that is after 45 years .They are as accurate as you are going to get, bouncing on a small craft in open ocean.
 
Does anyone know if Astra IIIb comes with a correction certificate that actually has corrections? I have found one at a good price but there is no correction certificate with it. I have seen photos of others that do come with a correction certificate but they all state 'zero correction' at all angles with wording that approximates to...........''this instrument is free of errors for practical use''
 
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Frank Holden said:
I have a Plath which has been in the family for 68 years, I also have a 1981 Freiberger Trommel-sextant ( ie Drum) that I bought off a sailor a few years ago. And last but not least I have an Inglis Smith yacht sextant with a frame about half the size of the other two. Japanese made and rebadged in limited numbers for a Victorian chandlery in about 1970.

We can ignore the latter as its the only one of them I have ever seen. Its optics are nothing flash.

The other two? On both the drum is simply calibrated to the nearest minute but its easy enough to read off to 1/10' just by inspection.

Optically the Freiberger has the brighter image of the two and slightly higher magnification. No surprise there as they were made by Carl Zeiss, Jena, who also made some of the best binoculars out there.

I've handled Tamayas and always found them very heavy compared with the Freiberger... which is a major consideration if you are taking stars. If the Astra is a Tamaya clone they may be the same weight.

My choice would be the Freiberger.

There is a seller on Ebay who seems to have cornered the market in 'as new' sextants coming off ships being broken up in India... I imagine he would be safe enough to deal with as I don't think anyone has got into the replica Freiberger market yet.

Some may find this of interest... the magazine only paid for 'first publication rights' so mine to do with as I wish ... written about 25 years ago..

https://www.dropbox.com/s/oxduof5rsz8zwtb/Offshore Navigation.pdf?dl=0
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This link goes to a 404 error today, though it did work last night- the pdf saved will not open either today.
Any chance of checking the link? I saw just enough to be interested!
 
steveej said:
A lot of the ones on e-bay seem to be coming from India from the ship breaker yards. I have been warned against these as they may be copies, lots around about £300 but a lot of money to waste if its fake.
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Would you like my plastic one to practise on? For cost of postage and packing, I don't need two sextants and trying to have a bit of a clear out, need the shelf space. I think you might have my email address, e is best but if not PM me.
 
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I bought a Davis Mk25 last year for a transatlantic. It was the first time I had used a sextant and on a long comfortable tradewinds passage I had plenty of time to learn how to use it and to learn it's quirks. The biggest problem was the backlash error was quite different depending which way you turned the mircometer. However, once I understood the error I was able to comfortably get within 5-8 miles of the GPS position and on one occasion came within 2 miles (although that might have been luck more than skill and sextant accuracy).

The plastic sextant is quite light to hold, and at first I would have preferred to have had the feel of something heavier. However, when you're spending an evening pointing pointing the sextant at stars it's actually nice to have a lighter one.

I found the Mk25 did everything I wanted. I was able to take sun, moon and star sighs comfortably. If all you are doing is trying to get an understanding of Astro Navigation and have some fun with a sextant that is reasonably accurate then you really don't need anything more than a Mk25. I would only spend the extra money (and it's quite a bit extra) if I was looking to seriously use the sextant as my primary means of navigation or if I really wanted the satisfaction of owning a beautiful bit of kit. To learn Astro Navigation and to have it as a backup on an ocean passage a Davis Mk25 is all your really need, and it does the job just fine.
 
BelleSerene said:
I just looked at the Davis instruments online. You mentioned the Mk 25 (as opposed to their slightly cheaper Mk 15). I would definitely go for the Mk 15 instead: they say they fit the Mk 25 with a whole-horizon mirror (as opposed to a traditional half-silvered one). The short story is that this makes the easy sights easier and the harder ones trickier: read about it in any sextant guide. After a few sights you'll tire of it, if the visibility's poor that really might affect the results you can get, and then you really will wish you had either a Mk 15 or any decent metal sextant![/INDENT]
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Having used the Mk25 I can't say the whole horizontal mirror caused me much difficulty. Maybe if I had already learnt to use a sextant with the traditional half-silvered mirror then it might have been a fuss getting used to a slightly different technique when finding my sights, but once you've done it a couple of times you'll be fine.

The other important difference between the Mk15 and the Mk25 is the Mk25 has an LED backlight that is triggered by pressing a button on the handle. That makes it very much easier to use when taking sights at night or dusk/dawn.
 
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Minn said:
Ten years ago a pound got you 15 RMB Yuan.

Today, thanks to Brexit, etc., a pound gets you around eight.
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Ten years ago, before Brexit you may well have got 15 to the pound. However, 9 years ago, also before well before Brexit you would have got only 9 to the pound.

Perhaps you and those clever currency traders were able look 8 years into the future to foresee the events of the summer 2016!!
 
Prasutigus said:
Would you like my plastic one to practise on? For cost of postage and packing, I don't need two sextants and trying to have a bit of a clear out, need the shelf space. I think you might have my email address, e is best but if not PM me.
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Jerry,

Thanks for your kind offer and I just sent you a PM. Hope all is going well with the theory.

Cheers
Steve
 
I've had a look, and it seems, forbye the fascinating tiny brass Goa copy-instrument on the shelf by the door, I have two - one is an Astra 111b presented to me by HRH The Princess Royal, and another is a Freiberger Drum job inherited form my F-in-l. He never used it. Both pristine....

I gather the GGR bods are required to use a sextant - and a mechanical log, a mechanical deck watch, and a manual means of working out WTFAW.
Their actual positions will be monitored night and day, electronically, and their navigation logs will be scrutinised for any signs of 'Crowhurstyness'. Some of the entrants have never before plotted an EP, reduced a sight, nor kept any kind of log.

Should be interesting....
 
I have a Simex Mk III sextant which I picked up off eBay for £160 a few years back. It dates back to the 70's and was made by Tamaya but badged Simex as they were supplied to a Capt Simonsen in the US. He taught navigation and signing up for one of his courses included getting the sextant at the end of the course. Mine was apparently used for navigating on the Great Lakes at one point. Lovely instrument, not often used but great to have. Always carried it in my hand baggage where it never fails to attract the attention of the security staff...
There's an Astra on eBay at the moment, two days or so to run with a current price of about £150. I found that the way to spot a bargain is to keep searching eBay, put up with trawling through all the fakes brass ones and just occasionally you'll come across one being sold in the wrong part of eBay by someone who doesn't realise its potential value and you'll get a bargain. Personally, after trying both the Ebco and Davis sextant, I'd far prefer to wait until I could get my hands on a metal sextant although the plastic ones are functional.
 
> Frieberger Yacht Sextant cheapest I have seen is £650

That's what we had and I would recommend it . One tip is you need to adjust the shades each time but the easiest way to find the horizon and sun is turn the sextant upside down find the sun then the horizon, then turn the right way up and fine tune it.
 
steveej said:
Does anyone know if Astra IIIb comes with a correction certificate that actually has corrections? I have found one at a good price but there is no correction certificate with it. I have seen photos of others that do come with a correction certificate but they all state 'zero correction' at all angles with wording that approximates to...........''this instrument is free of errors for practical use''
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My Astra 111B is 2004 vintage & has the certificate "free of errors" . It is unused & yesterday at Marchwood YC Astro Nav lecture, it was found to be free of all errors !
 
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