NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Bubble sextants on e-bay
From: Ken Gebhart
Date: 2007 Jan 01, 17:24 -0600
From: Ken Gebhart
Date: 2007 Jan 01, 17:24 -0600
Alex and others, I agree with Robert about the MK IX being good. We used to sell them for a while. My high school aged son overhauled them without any problems. There were 2 models: an A model which had no averager, and a B model which had a large cylindrical averager sticking out the forward end. The wind-up averager is really of no use unless you are shooting from an airplane, so we just sold the A model. When these ran out, we simply lopped off the averager of a B model with a hacksaw, and voila- it became an A model We probably have 50 to 100 of these left over in a self storage unit. I would be glad to sell some of these for, say- $50 each (which is mainly for the effort of digging through them to find the decent ones). For that matter, we also have piles of A-10s, A10As and AN 5851-1s too. I probably will never do anything with them, so if someone wants to come to Wichita with a trailer, I can make you a deal on the lot. The A-12 sextant used C size batteries whose covering was a cardboard sleeve (during the war). The design was to remove the sleeve and insert the batteries. You can still peel off the jacket of modern C cells, and insert them. They won't look pretty, but they work ok. If you like you can cover them with masking tape. Do not under any circumstances buy an A-10 or A10A on ebay (or from anywhere else for that matter). Not only are the bubble chambers probably dry and hard to fill, but 99% of them are frozen internally, due to poor lubricating design. Total disassembly is required to fix this problem. Even if you get the 1% that works, it will probably have horrible backlash. The AN 5851-1 (also known as the Navy mark V or the A-14) has the raduim lighting mentioned earlier, but the paint containing the radium has deteriorated over the years such that the radium light cannot get out very well. Most of them have 50% deterioration requiring well dark adapted eyes to shoot stars at night. Lastly, Alex, you prefaced your analysis of CN usage with the phrase "I think" Therefore, I can't say you are wrong. However, if you could stand in our booth during a boat show, and hear the favorable comments from passersby (in contrast to 10 years ago), or see the many people that come to our seminars, I think you would feel differently. Celestialis On 1/1/07 1:11 PM, "alex"wrote: > > Dear Robert, > Thank you very much for a lot of useful info. > >> If you are looking for a bubble sextant, there are only two that I would >> recommend without hesitation and in this order: >> >> British MK IX A > > Do you have any experience with AN 5851-1 (a.k.a. A14) recommended > by others? And its development A15 with variable-time averager? > >> You should purchase it from a reputable >> dealer who knows sextants and who has hopefully overhauled the unit you >> intend to purchase. > > I have not seen an e-bay dealer yet who sold an air sextant without a > disclaimer > that he does not know how to use it. My experience with e-bay so far > confirms > your example with 10 coins falling heads. > Of the 8 items I bought on e-bay so far, except books, 3 had hidden > defects and 3 were > badly damaged in the process of delivery (and I was never able to > collect any insurance). > >> As for where to find them, there are several dealers out there. Two come to >> mind: our own Ken Gebhart and Robert E. White &Sons of Boston >> Massachusetts. > > Robert White's web page does not seem to mention any air sextants. > And I did not know that Ken sells any used equipment that is not > listed in Celestaire catalog. > Ken, how to find out what antique items you have for sale? > > Alex. > > > --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to NavList@fer3.com To , send email to NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---