Sextant

Jul 4, 2015
436
Hunter 34 Menominee, MI; Sturgeon Bay WI
Can anyone please recommend a decent sextant to purchase either metal or plastic; have a landlubber friend interested in astronomy who would like to purchase one and learn how to use it
 
Nov 6, 2006
9,885
Hunter 34 Mandeville Louisiana
Check out the David MK 25 sextant. I had one and it was fine to learn on.
 

dLj

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Mar 23, 2017
3,374
Belliure 41 Sailing back to the Chesapeake
How accurate does you friend want? How about stability and longevity? Are they concerns?

dj
 
Jul 4, 2015
436
Hunter 34 Menominee, MI; Sturgeon Bay WI
Not of concern; he will not be navigating; would just like to learn the principles and try using it. Will never be used on a body of water!
 
Oct 22, 2014
20,995
CAL 35 Cruiser #21 moored EVERETT WA
The David is plastic it is a training tool. Accuracy is limited to several miles and based on good math skills and proper Nautical Alamnac to be able to adjust for the refraction error. The Mk25 should get you within a minute or two which should be good for 2 or so nautical miles. On the open sea that should get you on the correct coastal location to find your harbor. After all safe harbor is everything after a long sea passage.
 
Nov 6, 2006
9,885
Hunter 34 Mandeville Louisiana

I found it was accurate but was sensitive to how hard ya squeezed it while holding and big temperature changes made a difference too.. As John said, a fine training tool.. We used it on our first Gulf of Mexico crossing back in '89 and got fixes that were 3-4 miles off of what the LORAN said; plenty accurate for big water..
 
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Jan 19, 2010
1,169
Catalina 34 Casco Bay
Astronomy..... get the SKY VIEW LITE APP... IT'S FREE !!!! names EVERYTHING in the heavens and shows their arc of trajectory....
 
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Oct 10, 2019
114
Signet 20 0 Ithaca

There's this, the self proclaimed world's cheapest sextant, looks like plasticised cardboard, probably enough to learn by, and under $30.

I've always been a fan of getting the best tool I can afford; even if I don't use it often, it's always a pleasure to work with a high quality implement. Not saying your friend should drop $1100 on a sextant just to fool around in the backyard, though...
 
Jun 29, 2010
1,287
Beneteau First 235 Lake Minnetonka, MN
Here we go..... someone wants to learn how to use a Sextant because they want to do it for FUN. The Mark 15 or 25 from Davis is perfectly fine for that. I have a 15 myself. Recommending apps for your phone, talking about accuracy at sea and what not is not helpful as that is not what the person wants to do. Some people just want to learn how to do it for themselves. Really, there are people that do that. It's called educating yourself and learning something new and interesting to yourself. As was stated a couple of times by the OP, their friend has an interest and just wants to learn how it is done.

One other thing, I don't think mine has been out of the box more then a handful of times and none of those times were to do any sights....... So, spending a little is prudent in the beginning. Would I like an Astra IIIB? Sure but, expensive dust collector in my house.
 
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Oct 10, 2019
114
Signet 20 0 Ithaca
Will never be used on a body of water!
And therein lies the shame, if you're a boater (assume you are, or you wouldn't be posting here) you should make him practice on the water, it is a "marine" navigation tool after all...
 
Jun 21, 2004
2,532
Beneteau 343 Slidell, LA
I purchased a Davis Mark 15 a few years ago when I was taking a celestial navigation course. Not the best for world wide voyages, but plenty good enough to learn navigation. There are a few used ones on Ebay for under $100. BTW, the US Power Squadron is one of the few organizations that continue to teach celestial navigation; highly recommended for a very reasonable cost.
 
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Feb 14, 2014
7,400
Hunter 430 Waveland, MS
Interesting that most sailors want to find where they are with a sextant.

But...

What if you know where you are, then why a sextant?

Simple answer...

The angle of any bright star in the clear night sky!

Thus Astro-metrical use !!;)
Jim...
 
Jul 4, 2015
436
Hunter 34 Menominee, MI; Sturgeon Bay WI
And therein lies the shame, if you're a boater (assume you are, or you wouldn't be posting here) you should make him practice on the water, it is a "marine" navigation tool after all...
He's just curious and doesn't boat
 
Jul 4, 2015
436
Hunter 34 Menominee, MI; Sturgeon Bay WI
I purchased a Davis Mark 15 a few years ago when I was taking a celestial navigation course. Not the best for world wide voyages, but plenty good enough to learn navigation. There are a few used ones on Ebay for under $100. BTW, the US Power Squadron is one of the few organizations that continue to teach celestial navigation; highly recommended for a very reasonable cost.
Thanks, did not know that as I myself may look into this as I have wanted to learn as well!
 
Jul 4, 2015
436
Hunter 34 Menominee, MI; Sturgeon Bay WI
Thank you everyone for your answers; I will pass them on to him. I personally will look into the US Power Squadron course. You have been very helpful.
 
Oct 22, 2014
20,995
CAL 35 Cruiser #21 moored EVERETT WA
I like the idea of learning a skill just to learn the skill. @Ilanortho please share with your friend ”Go for it!”
We go around only once.
 
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