As a remark, the targeted mountain farm is roughly 2.4 km or 1.5 miles away from my shop.

Not in a million years would I have thought to measure anything in my shop with a land surveying tool... *salute*

Thank you so much! Because of this video, today I was able to recognize a Wild T3 theodolite buried in the back of an antique shop in central Jakarta! I had never even heard of a theodolite two months ago. Now I own one. _Next_ I need a dividing head I can test for accuracy. Once I have the dividing head, _then_ I can justify a mill. My life has direction again.

Awesome! ATB, Robin

I’d love to see a series of videos with you and Stefan Gotteswinter having casual conversations about concepts like “pretty good”, “not to shabby” and “perfect, at least.” It. Would. Be. Amazing.

As soon as I saw "Wilde" on the instrument I knew you had an outstanding unit!! Thank you for showing us that excellent example of workmanship.

Sunday morning, up at the lake, having a coffee, life is great! Why is it then that this video makes me wish that I was 3 hours south, at home and in my shop? Awesome video Alex. Thanks to you from a very humble Canadian. Cheers.

That theodolite is a beautiful machine, and so is the dividing head. Very interesting stuff. I can't get enough of this workshop-geometry type video. Thanks, Craig

There are two errors to consider in the use of the Theadolite. 1rst error as you mentioned is machine error. This is the circle indice accuracy. Also not being absolutely perpendicular/level to the circle plane. 2nd error is user error. This is called parralax. Parralax is caused by the the angle of the human eye looking around the stadia. A learned and experienced surveyor knows how to move the eye and head back and forth (left to right, right to left) to zero the parralax error consistently. During my training, I was amazed at how much angular error can be intruduced by not limiting parralax error to a minimum.

always very interesting the use of tools and instruments that were not realy designed for the job, but there functions are perfect. brilliant!

Thanks Alex - very interesting and what a great device - looks brand new

Very interesting - thanks. That theodolite is a work of art!

First. Thank you Alex for the great content! Your channel and content are fantastic, so much to learn.

I worked for an engineering firm 50 years ago as a rodman, and that is the same theodolite we used, the civil engineer referred to it as a transit. I enjoyed the video, and i did not realize how delicately accurate those instrument are, cheers!

Cool. A great example of "thinking out of the box". Very ingenious Alex.

Excellent presentation and analysis. I assumed you would use some optical method to check angles, but that theodolite is a thing of beauty! I feel,like it deserves a video just about it! And Gons are new to me, have to add that to my list of obscure units.

Very nice testing demo. Love it.

Excellent content! Yet again!

Excellent explanation. Entertaining and informative.

your like the first Austrian guy who's English and accent doesn't hurt my brains. Thank you. Subscribed :)

Very ingenious, good work!

Nicely done and very informative.

Fantastic video! Clever use of the tool!

Thanks for the memories! I was an instrumentman on a geodetic survey party with the California Division of Highways in the late 1960s to early 1970s. I used a Wild T2 and T3, Kern DKM3, Askania 3E theodilites and AGA model 4D and model 6 geodimeters. Looking back now, fifty years later, 'mountaintop-to-mountaintop surveying were the best years of my life.

Very interesting. It's a shame these mechanical devices are being scrapped out. Thank goodness there are people like yourself to save them.

An interesting test setup Alex.

Hiya Alex, Melbourne Australia here. I'm 53 and manufacture electric motors, can do nearly anything, but I had never seen how a theodolite worked before. I looked at Halley's Comet through one, but always wondered how they work. Now i'm that much smarter, thank you for a really well made video. Top work, as we would say around here. Subscribed too. Sincere regards, John.

That is quite the instrument, thanks for sharing. Charles

An obvious sinusoidal pattern with one extreme outlier. The sine wave would be from manufacturing error from one of the process machines at the theodolite factory. The extreme outlier would be from a wear pattern from improper usage or assembly damage. I've used a laser collimator for reflecting telescopes to project a beam onto a remote target, measure the offset, then calculate the error. Providing sub arc-second capacity!

looks almost exactly like my Wanderer-Were TKD-2! nice adaptation of precision measurement, cheers from Brooklyn

Clear explanations. Thanks!

Nice tool can't say I ever seen video on this. Thanks

Glad I got to see this instrument being used. It's very interesting to me. Thanks for the video.

What a mechanical piece of art!

Alex, that was a surprise, an interesting one. I will be watching for the manufacture of that worm gear. Which of course would be made easier on the repaired external drive deviding head! Ask ToT for a use of his time travel device, sorry, I digress. That theodolite is a work of art, thank you for showing it off, and it's travel case. I shal be on the look out for one...

Great video and instrument.

Any theodolite day is a good day.

Given the sinusoidal error, I think you find at least some of the error is due to the axis of the T2 not being coincident with the axis of the dividing head. Try doing the same test, but sight on a close target instead, say 2-3 m away. This will magnify any lack of concentricity. An excellent textbook on this type of measurement is “Optical Tooling” by Phillip Kissam.

This is excellent, new subscriber!! Great job.

Brilliant! 👏

Hi, Alex. Wow, what a find! My dad (1931-2009) worked at WILD Heerbrugg for many years in the prototype department. And, among other machines, on a MIKRON milling machine.

Interesting content, and what a cool instrument. Keep the good engineering content coming.

Very interesting video, thank you. Stay safe.

That was a very good video I subscribed.

Thank for sharing, I’m interesting

I would be very interested to see what the index errors are using the index plate and worm dividing function of the Walter. The direct index function utilizes a straight pin in the index plate which would account for the errors in your measurements albeit very good for a shot pin arrangement. All the best, Tom

Thats a cool way of checking accuracy! Ive got a T1A. And its divisions are in degrees. I dont think its as accurate as your theodolite. Keep up the great work. 👍

Nice work! Wonderful instrument. The Wild T2 is my dream theodolite (I have to make do with Zeiss/Jena Theo010s at the moment)... Plus, fun fact: sin(1") = 1/206264.8 which means on a 75 mm radius index circle, 25" corresponds to 9.1 μm offset. So, after 1 full revolution, the indexing pin locates again to better than 1/100 mm (which could be due to a bit of play because of an oil film somewhere being pushed one way or the other).

I am curious now as to what, if any, features possessed by this specific theolodite are different or more accurate than others. I can grasp what I see now, but I am probably never going to find either of these tools. In my experience, stuff like this is kind of near impossible to find in the States. I often look abroad to find high precision manual tooling for my work. Any thoughts on what features an "obtainable" non-hyper specialized theolodite needs to have to duplicate this? I've only seen the things on large stands for surveying use, never anything compact like this. Now that I get how it works, could you use one in reverse- to manually adjust machining to be more angularly accurate? This is why I love your channel- you test accuracy as the main goal. Most people have never seen anyone do what you do.

Great video some how I missed this video of yours. Now I need to buy a T2. On one of my many trips to Antarctica and South Pole There was the crew assembling 11 meter telescope mirror which is made of 100-200 approx sections. Each section was adjusted and calibrated with a centrally mounted Theodolite.

Awesome video Alex!

Or simply mount a rifle scope on the dividing head with the former's axis in line with the latter's face, and have the scope pointing at a target at a distance say 10 yards for an MOA scope or 10m for a MIL scope. Values can then be extrapolated by simple maths. Of course a better way would be to use a rotary encoder with even finer resolutions.

Best way is to use autocollimator and reference poligon mirror...

I think those instruments came from nearby Dornbirn, AT, nicht Wahr? Are you from CH or AT, oder? Nice test! A friend of mine had a Moore 1442 precision divider, which would have been a nice comparison tool...and, yes, the lack of backlash in the adjustments is wonderful!

Interesting. Worm gear accuracy of dividing head would also be interesting to check.

Excellent work. Also, first!

Enjoyed this. sub'd.

I would love to buy one of these mechanical transisite. How much did you pay for one of these ?? Nice work fella too. Peace

Nice video. Now we want to know how close the other index plates are. ;)

Respekt ✊

It is hard to find Walter UTAs in the USA - I've been looking a long time now..

Fantastic method for checking the dividing head! The one thing I'd suggest changing on your technique would be to aim at the *corner* of one of the barn windows, laying the crosshairs along the edges, rather than trying to choose a center point in the window. I learned surveying in college using a degree-reading T2, otherwise very similar to your instrument.

A video from you and GTWR in the same day, we are being spoilt. 👍 Trouble is i now feel wholly inadequate, time to find another hobby methinks.😢

I own a 1955 T-2, previously used by Lockheed to build airplanes. I bought the instrument for boundary surveying and construction surveying in 1975. Unbeknownst to me the instrument was dropped in the early nineties. The horizontal brackets were broken. Do you know of someone who restores the T-2. Thank you.

Are you using Doka boards for tops of workbenches?

I found a US military study that determined *field accuracy* of the t2 to be +/- 2,15 arc-sec over a large number of readings on targets about 12-15 km away, using a 125 mm illuminated target... apps.dtic.mil/dtic/tr/fulltext/u2/642295.pdf One of my best friends had a Moore divider 1440 (+/- 0,1") and autocollimators, I think a T2, and a Geneva jig borer (with laser interferometer "DRO") in his basement...you would have liked to play there...

Theo-Yodel-ite? :)

UTA - Universeller Teilapparat?

Wow, this was really great. And it raised a few questions and comments to be made. 1. You checked and adjusted that the axis of rotation of the divider was perpendicular to the plane of the theodolite. Isn't it equally important to check that the two axes of rotation are coinciding besides using the centring bushes you used when mounting the instrument to the divider? Or did the distance of your target across the valley negate the possible error? 2. I have always kind of wondered if a theodolite could be used in place of an autocollimator for machine tool or granite plate flatness measuring purposes. I guess that 0.5 arcsecond graduations are not fine enough but maybe modern theodolites have finer resolutions and accuracy. But what about the optics and the accuracy obtainable from targeting from a small distance such as within a room or building, say less than 50 meters? I've been told that theodolite accuracy diminishes as the target get's closer to the instrument. What do you think? 3. I have worked with a land surveyor friend in the past and had the privilege of operating a Leica electronic theodolite for a few days ( i think it was considered a total station, it had distance measuring feature incorporated to it, but no gps) and boy what a beautiful and precise instrument it was, and user friendly. I 've also had my hands on a Japanese Topcon unit and you could tell there was a difference. 4. Now I know the next time I'll be touring around the beautiful Austrian valleys (the route from Brenner to Innsbruck is probably one of my favourites) I won't just be looking out for beautiful scenery but also for great home machine shops. All the best, Dimitris

Ah, all my comments have been deleted... :sadface:

I'll bet a small fortune you can't find a Chinese made theodolite with this kind of pedigree.