A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Joel Jacobs
Date: 2009 Jan 08, 23:44 +0000
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-------------- Original message from "Joel Jacobs" <email@example.com>: --------------
Trevor,The only people I know who were around back then and might have knowledge of this topic is the past president of Tamaya, and Ken Gebhart. Ken at the time was buying his Tamaya sextants from Nautech. Now the situation is reversed, and I am buying our new sextants from Celestaire. If there are any others who have the knowledge you seek, I would be pleased to hear what they have to say.Simply stated, as far as I know the Nautech Master was made by Tamaya, Ginza. However, there were two companies with the name of Tamaya, and I never knew what the relationship was between them because my association was with Tamaya, Ginza, Tokio. The other company was Tamaya, Osaka, and you will see sextants of the type which interest you with their certificate and imprint. I always thought they were the source of the cheap private label instruments.As a coincidence, there is a Tamaya 633 listed on eBay right now. See http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=270324682768&indexURL=0&photoDisplayType=2#ebayphotohostingNote the name and the cartouche logo on the picture of the certificate. They are clearly that of the OSAKA Tamaya. This company was realy second rate and no one that I knew in the business had anything to do with it. It had no presence in the United States back in the 70's of which I am aware.And yes, of course there were quality differences between the lower cost sextants and the higher cost Japanese sextants. For example, if you compare them side by side, you will see that the materials, machining, optics, fittings, accessories are all of lesser quality. It is visually obvious with out having to put the instrument on a collimeter (test bed). More importantly, better grade contemporary sextants are built to a standard of non-adjustable instrument error not greater than 20 arc seconds. The best grade sextants such as the C. Plath Navistar Classic was built to a standard of non-adjustable instrument error of 10 arc seconds. I have no recall what the standards were thirty years ago, but I am sure it was significantly different than today, and still accounted for much of the difference in price.Ken Gebhart should speak for himself on this, but in my opinion, the Astra sextant and it fore-bearers design was not based on Japanese sextants. Its quality is superior to the lesser quality Japanese sextants of the 1970's and equal to the quality of the best Japanese sextants of today. We consider it a Best Buy compared to either the current Tamaya, Cassens & Plath or Freiberger.Since you and I are the only ones contributing to this thread unless I see some group interest in this discussion, I really don't have any further time to spend on it.All the best,Joel Jacobs--
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-------------- Original message from "Trevor J. Kenchington" <Gadus@istar.ca>: --------------
Thank you for taking the time to write. I had found three of the four
archived postings that you noted, plus a bunch of others, though I
com/arc/rather than http://www.irbs. com/
. as I said before: It wasn't hard to find those,
just difficult to extract answers to specific questions from them --
likely impossible in the case of my questions, since those seem not
to have been addressed before.
> About the MS 633 and private label sextants
> In respect to the MS 633, if that was the same as the economy
> sextants made or distributed by Nautech, Simex, and Mac, that all
> had the same features, they were private label sextants and not of
> the same quality as the upscale Tamaya sextants. We sold our
> version under the brand Nautech Master. You can compare this
> picture and features to the above and should find them close to the
> same. See http://www.maritime
-antiques. com/boatblog/ nautech-
I agree that that Nautech Master looks essentially the same as the
Tamaya 633 and the Simex and MAC equivalents.
I still don't think that I _know_ what those various sextants were
but I will try a hypothesis for others to shoot down if they have
In the 1970s and into the 1980s, Tamaya built and sold a line of high-
quality sextants that were the fore-runners of the current "733
Spica". Those instruments had the model numbers 635, 636 and 637,
depending on which telescope was sold with them.
At the same time, one or more manufacturers built a lower-cost, lower-
quality line of sextants which Tamaya sold (only in Japan perhaps?)
under model number 633 and which was imported to North America under
a number of labels, including Nautech Master, Simex Mariner and MAC.
I assume that whether there was one manufacturer or more than one
makes little difference, since the sextant designs were essentially
identical, but maybe that is wrong. One manufacturer may have had
higher quality-control standards.
If that is more or less the story, it raises another question: What
was the difference in quality between the two lines? Did the 633 bear
the same relationship to the 635-7 that the modern Jupiter bears to
the Spica? Or is it more like the relationship between the Astra and
the Spica? If a Tamaya 633 is merely an older equivalent to an Astra,
it would be hard to justify the prices that some of them sell for!