What Sextant would you recommend.

FullCircle

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I am minded to take up a bit of a hobby and buy a sextant.
I may or may not use it, but I want something that is useable and accurate that I can get bits for, and have it serviced.

Any recommendations for something worthwhile but wont make my eyes water?

Also, what to look out for, and approx cost used in good working order?
 
Good ones are expensive second hand and very expensive new. I've heard good tails of the modern plastic ones but not sure I would like to rely on one of these. Ours is a reassuringly expensive ZEISS in a nice strong box.


I did have an Ebbco plastic, but it didnt look up to the job.


Thanks, any particular model you have, how old is it, are there any startling changes between a WWII military one and a flashy 21st century?
 
I have an Ebbco plastic sextant. They are OK to use and can be accurate enough. Another low cost plastic sextant is made by Davis. If you are not going to use it for serious work then nothing is wrong with a plastic one.
 
The one I lug about is a plastic Davies Mk 15. Light, easy to use, spares no problem. Not so good for stars, but perfectly adequate for Sun, moon and planets. Used extensively offshore.

Also got a Celestaire, but more costly. Will use it if not flying to/from a boat. Dogs doodahs for stars.

Hope this helps.
 
A Davis Mk15 or a Mk25 would be ok. You should calibrate before each use, then they are acceptably accurate.
The problem with buying a second hand metal sextant is that if it's been dropped at some point it may be completely useless.
 
I am minded to take up a bit of a hobby and buy a sextant.
I may or may not use it, but I want something that is useable and accurate that I can get bits for, and have it serviced.

Any recommendations for something worthwhile but wont make my eyes water?

Also, what to look out for, and approx cost used in good working order?

The Astra IIIB ( see here ) is given as an annual prize by the RYA and the Royal Institute of Navigation, usually by the fair hand of a Royal, so such an instrument comes well approved.

One can spend a whole lot more for a top Zeiss, Tamaya or Cassens and Plath, but while that might enhance bragging rights, it'll do nothing much for the quality of your sights or ease of use.

Have a Google for the 'Astra IIIB' and read some of the revues and comments.... :)
 
Normal ebay rules & risks apply but good ones are there to be found.

Plastic ones can be perfectly adequate.

I have a C&P Sailing Sextant and this is a delight to use and own.

I believe that the biggest difference between plastic and metal is the quality of the optics. Many recreational sailors who commit to learning celestial navigation are content with sun-run-sun or sun MP sights. Plastic sextants perform adequately for these. If you progress to deriving a three point fix from selected stars (using AP 3270 Vol 1, for example), the optics in a plastic sextant aren't up to chasing the little bug-gars, imho.

Buy a decent plastic one now (Davis Mk 15 or 25) and bide your time to hunt down a bargain on ebay would be my advice.
 
The Astra IIIB ( see here ) is given as an annual prize by the RYA and the Royal Institute of Navigation, usually by the fair hand of a Royal, so such an instrument comes well approved.

One can spend a whole lot more for a top Zeiss, Tamaya or Cassens and Plath, but while that might enhance bragging rights, it'll do nothing much for the quality of your sights or ease of use.

Have a Google for the 'Astra IIIB' and read some of the revues and comments.... :)

Hmm, 499 quid at TCS...... or 550 quid from the RYA
 
Whatever you go for, go in person and take someone who knows a bit about them. Among other things, inspect the factory calibration certificate usually found inside the box lid.

Look at several. The 'table of errors' on the unit you choose should list very small errors, and the changes at different angles of arc should also be small - no jumps from e.g. +1.5' at 10 degrees to e.g. -6' of arc at 20 degrees. Reject any unit where a certificated error exceeds, say, 5' of arc. There will be a better instrument somewhere on the shelf.

There are 'Friday Night Cars' among sextants, so leave those for some other unsuspecting noob. :)
 
I am minded to take up a bit of a hobby and buy a sextant.
I may or may not use it, but I want something that is useable and accurate that I can get bits for, and have it serviced.

Any recommendations for something worthwhile but wont make my eyes water?

Also, what to look out for, and approx cost used in good working order?

A plastic sextant is good enough to find your way with - I've done it, but my eyes were younger then. I then bought an ex-WW II US Navy sextant, with rather better optics. It's now 70 years old and works perfectly, though the new sextants nowadays have still better optics.

There is virtually nothing to go wrong on a sextant, other than the silvering on the mirrors, unless you misuse or drop it, in which case it is either plastic scrap or a pretty antique decoration.

If you buy secondhand either go with someone who knows what can be wrong if damaged, or buy from a knowledgeable dealer. Chart agents in big ports sometimes have S/H sextants for sale.
 
I second capnsensible on the Davis Mk 15 if airplanes are ever involved: Something like an Astra IIIB in its box would take half your baggage allowance.

Adjusting the Davis takes less than a minute. I'm happy with mine and have successfully used it for star sights, although I admit to not having much to compare it with: only time I used a metal sextant was in daylight on a YM Ocean theory course 3 years ago.

The Davis sextants have looked a bit overpriced recently (more in GBP than they are in USD in the US). Googling current prices Marinestore (who I've never tried) seem to have the cheapest deal (£157.34 inc vat+delivery)
 
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I have a Davis. Use it twice a year to keep my hand at it.

I would not buy an expensive sextant in this day and age.

You can get an iPad II with iNavx for under £600 plus a Garmin GPS 76 for £250.

Unless the USA pull the plug on the system, there is no reason to pay silly money for a sextant... opinion :D
 
I think it would be a really good idea, if you didnt want to pay silly money for a sextant and wanted to learn how to use one for fun, to ask about it on a sailing forum and get your question replied to by loadsa people who have lots of experience using one.

Opinion.....
 
I reckon you should buy the cheapest plastic sextant, about £50 and play with it to get the basics, and then if you like it and can work it, you will have a better idea of whether it's worth shelling out large quantities of money for a decent one.

I've got both Mary Blewitt's and Lt Cmdr Rantzen's books on the subject which you are welcome to. (Although I'm informed that Cunliffe is better).
 
I reckon you should buy the cheapest plastic sextant, about £50 and play with it to get the basics, and then if you like it and can work it, you will have a better idea of whether it's worth shelling out large quantities of money for a decent one.

I've got both Mary Blewitt's and Lt Cmdr Rantzen's books on the subject which you are welcome to. (Although I'm informed that Cunliffe is better).

Col,
I now have Cunliffe sitting on the Kindle.....
 
I am minded to take up a bit of a hobby and buy a sextant.
I may or may not use it, but I want something that is useable and accurate that I can get bits for, and have it serviced.

Any recommendations for something worthwhile but wont make my eyes water?

Also, what to look out for, and approx cost used in good working order?

Jim,

I've got Zeiss yacht sextant sitting around. I bought it years ago when I did my YM Ocean Theory. Don't use it now.

I'd be very happy to lend it to you for a while.

Neal
 
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