Ebay item arrived yesterday; survey transit circa 1942. Needs cleaning, including cleaning the plates, but before trying this at home, does anybody have any sage advice?
Is there any sort of repair manual for Gurley transits of this era?
Also looking for the 49th Edition: 1941 GURLEY MANUAL of SURVEYING INSTRUMENTS
Or is the repair manual part of the users manual?
Last question: Is this reading of 221?ø47'20" correct for the image above? I can't remember, but think it was about 1977 when we had to read the dinky vertical angle vernier mounted on the big HP distant meter to the minute. Haven't done it since and never to 20". It would be impossible to read without my cell phone!
Thank you all for your much appreciated help.
It's been many years for me, as well. I believe you are looking at the angles left scale. On the angles right scale I get 138-10-00, but without the tool to manipulate, I'm not sure I'm reading the vernier correctly.
I would be very cautious cleaning older instruments. I unglued the lenses on a very nice antique level once. It turned out really pretty, and the parts sold for $40 when I was done.
I have the 47 Gurley manual. It goes into good detail on generakl maintenance and cleaning. You can find them on fleabay pretty cheap if you want a daily reader copy. I would scan mine but it would crack the spine to open it up that far...
Is this reading of 221?ø47'20" correct for the image above?
I read it as 221?ø47'40", or even 221?ø48'00" but could easily be off one 20" mark either way. That would be angle-right 138?ø12'00" By comparing the left and right vernier coincidences and how far nearby marks are from coincidence, I favor 40", but the dust specks interfere on both sides.
Anyway, I think you have the principle correct.
?ÿ
@bill93 Yes, after I posted the original message 40" seemed like a better call. And all of that dust on the plates was what has me hunting for a repair manual to study before deciding to do anything about it. Thank you for affirming methodology as well as angular direction.
...
Is there any sort of repair manual for Gurley transits of this era?
Also looking for the 49th Edition: 1941 GURLEY MANUAL of SURVEYING INSTRUMENTS
Or is the repair manual part of the users manual?
..
You can find some manuals in PDF on the site below.?ÿ I don't see the 1941 manual, but you can see what is in the manuals.?ÿ The manual does go over adjusting the instrument and caring for it.?ÿ The site has a lot of great information.
http://www.compleatsurveyor.com/eReferenceCatalogs/eRefCats.html
@joe-b Thank you for the link to the old catalogs, great resource!
What I was hoping to find was a service manual, without which, the dust on the plates will have to wait before I think about how best to take things apart and clean them.
