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62 mm prism with 5/8 on top

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john-hamilton
(@john-hamilton)
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We use 25 mm mini prisms for almost everything, and the seco model we use has a 5/8 thread on top so that we can put a GPS receiver or antenna on top of the prism. The prism itself tilts but the prism holder does not.?ÿ

However, sometimes we need a larger prism for longer distances. I had a very old topcon prism (non tilting) with the 5/8 on top, but I dropped it recently and it broke. We have several 62 mm prisms that tilt but do not have the 5/8 thread on top.

I looked on Seco but could not find a 62 mm prism with 5/8 thread on top. Anyone know of another source? Offset does not matter, I will determine that on a CBL and enter it as needed.?ÿ

 
Posted : May 22, 2019 3:21 am
(@paul-in-pa)
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Did you break the prism or the case. In the past I have purchased Chinese prisms only on ebay that screw into the Topcon case. They break very easily, in fact once I bought a pair, had them in the Jeep, installed one for first backsight shot of the day, crossed the street and was at my setup when a heavy gust, took out the setup before I even got the shot. Very glad I had the second one. Cheap to buy, but still sometimes you do not get your money's worth.

What do you consider longer distance? I have taken 1,000' shots with a mini, at which distance the target size is more important that the prism size.?ÿ

Paul in PA

 
Posted : May 22, 2019 4:26 am
john-hamilton
(@john-hamilton)
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broke the holder. I have a monitoring project that I do 6 times a year that has a 6000' sight. Several others that have sights significantly over 1000'. We were running a monitoring traverse (now completed) every week that had one sight just a bit too far for a mini prism. So there is occasional use for a bigger prism. 

 
Posted : May 22, 2019 5:44 am
 jaro
(@jaro)
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Would this work?

https://www.surveying.com/en/62-mm-nodal-point-prism-assembly.html

edit, never mind, I think those threads on on the tilting portion.

Try this

https://www.hayesinstrument.com/st_prod.html?p_prodid=2191

 
Posted : May 22, 2019 6:41 am
john-hamilton
(@john-hamilton)
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I just bought some triples and a single that someone sent pics of. Thanks, Dave.?ÿ

 
Posted : May 22, 2019 7:14 am

john-hamilton
(@john-hamilton)
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Yea, the first one I already have, it tilts. Second one is what I need. 

 
Posted : May 22, 2019 7:15 am
a-harris
(@a-harris)
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I have a triple with prisms and single w/o prism omni type prism extra that need a good home.

 
Posted : May 22, 2019 7:46 am
(@jerrys)
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We sell the mount you are looking for with the 5/8"X11 male thread on top.?ÿ "www. hayesinstrument.com" as a public service only...

 
Posted : May 23, 2019 1:30 pm
john-hamilton
(@john-hamilton)
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Thanks, got a great deal on some used ones that were not being used anymore. 

 
Posted : May 23, 2019 1:42 pm
(@steven-metelsky)
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