Plastic Classic Forum

I had a question about sextants. I’m looking to purchase one that’s reliable, and somewhat cost efficient. Didn’t know if y’all might have any info or input. Thanks a lot!

I have a Davis Mark 15 which seems to me to be plenty nice and gets lots of good reviews over the years, but is not their top of the line. They have really come down in price over the years - I guess GPS has contributed - only $150 or so now.... !!!

I also have their plastic "practice" sextant, the Mark 3, as a backup and which I have read accounts of it being accurate enough that it has been used as a primary nav tool when needed, and it performed well.

Of interest to me is Sven Yrvind's "Bris Sextant", a tiny device he uses to takes sights. I have not used it but find it intrguing to no end. http://www.yrvind.com/bris-sextant-for-sale/

Thanks for the response CapnK. I’ve seen the Davis Mark 25 that you’re talking about. Do you think the plastic would not distort in temperate climates, as long as it stayed in the case when not in use? I’m preparing for a circumnav, and even though I’ll have gps, I will be doing most of my nav using the sextant. Thanks again

The Davis 15 should be OK. I have a Davis 25 which I prefer for the full horizon mirror that I find easier to use. The 15 may also lack illumination but that's not essential if you have a headlamp. The plastic may distort over time in some situations but I've had good luck with mine and found the instrument error stays within 1 mile. It does require simple adjustment of the mirror screws from time to time. Typically there is a total of 3 miles potential error - 1 mile for the instrument, 1 for the tables and 1 for the operator unless the sea is very rough. I used to have an aluminum Astra IIIb that soon became useless because the paint was applied poorly and flaked off and the aluminum corroded making the vernier scale and drum impossible to read. You might find a good price on a used German or Japanese sextant that could be more accurate over time unless you are unlucky and get a damaged one. If you buy the Davis I would test it soon in case you want to exchange it if you found a manufacturing defect. Or if you are passing through Brunswick, GA you can try out my Davis to see if that model is the one you want.

I really appreciate the help and info. I went ahead and ordered the 25, so I’ll try it out in a few days.

And I’m looking at being in Brunswick, the first 2-3 weeks of July, so I’ll see you then. Thanks again

BTW - If you are heading down the east coast on your way, I'm in Georgetown, SC.