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Vintage Brunson high accuracy machinist level/telescope current application

mjk

Titanium
Joined
Oct 20, 2005
Location
Wilmington DE USA
Found a Brunson high accuracy machinist level labeled machinist telescope at resale shop.
It may be gone when I go back, but I thought I'd ask if anyone has any experience or used to
Approximately 20" long x 3" diam
horizontal ,vertical adjustment near eyepiece
& focus dial

A bare tool not mounted in a fixture, but in a fitted case.
are these still used for anything?


yes pic would be helpful
 
I'd really need a better description of the instrument to talk specifics, but your description could be either a "dumpy level" or an "alignment telescope".

A dumpy level was, several decades ago, more of a civil engineering or surveying instrument than a millwright or machinist instrument. The same jobs today could be done using GPS, by "trigonometric leveling" with a theodolite, or by using an "automatic level".

An alignment telescope was, and to a limited extent still is, used mainly to check the colinearity of a series of bearings, as for a turbine or a crankshaft.

Neither instrument is of much use without a number of accessories. The dumpy level needs at least a tripod and a leveling rod. The alignment telescope needs some form of mounting bracket, special targets, target holders, and micrometer or dial gage center the target in its journal.

I'd probably jump on either instrument if the price was fair, but I've spent 42 years of my working life doing optical tooling and industrial alignment of one sort or another. I have soft spots in both my heart and head for the instruments I've used over those years.
 
Went for it, a donation to HfH.
It may end up like the 42" vernier calipers I have......looks neat,don't have an immediate use ofr it

"Barrel" measures 2.25
Fiberglass foam lined case with heavy cast aluminum latches and handles would test UPS's worst drivers

0310211230.jpg0310211230a.jpg0310211231.jpg0310211231a.jpg
 
If it's in working order you might use it often.

I was told I needed a laser when I started building things. I grew to hate that thing. Not the kind of accuracy I had hoped for.

I bought a cheap optical transit. Calibrated it myself and fell in love with it.

When a helper killed that transit I bought a super nice Lietz optical transit. Pretty sweet.

Set my bridge crane runway within .010" over 60 feet.
 
That's an "alignment telescope". The cylindrical barrel is ground to a diameter of 2.2495 inch, +0.0003 inch, -0.0000 inch, with no more than 0.0001 inch taper (if I'm remembering right). The telescope Line of Sight is, when correctly adjusted, parallel to the barrel axis within 1 arcsecond, and centered within 0.001 inch.

Brunson Instrument no longer makes that particular model of alignment telescope, which was a Brunson design, but has replaced it and most other Brunson-designed alignment telescopes in their lineup with instruments designed by Keuffel + Esser. K+E had been Brunson's major competitor in the optical tooling business, but essentially went broke when they tried to change their business model from made-on-order to deliver-from-stock shortly before a big economic slowdown. Brunson bought the K+E optical tooling business, and moved the K+E instruments that they thought superior to the Brunson-design instruments into the Brunson lineup in place of the Brunson-design instruments.

I'll STRONGLY suggest you spend some time on Brunson's website, especially in the "knowledgebase" section. Knowledgebase
 
Found a Brunson high accuracy machinist level labeled machinist telescope at resale shop.
It may be gone when I go back, but I thought I'd ask if anyone has any experience or used to
Approximately 20" long x 3" diam
horizontal ,vertical adjustment near eyepiece
& focus dial

A bare tool not mounted in a fixture, but in a fitted case.
are these still used for anything?


yes pic would be helpful

What John just said.

CAVEAT: I was taught this in '61 field-only, but Dad had been US Coast & Geodetic Survey BEFORE NACA (1931-1936) and Corps of Engineers, (1936-1967) so he saw to it I got it righter than wronger...

:)

Then again "formally" in '66, at Belvoir, classroom AND field... BUT...haven't used anything more complicated than a Locke level SINCE. The need just didn't happen to cross my radar.

OTOH, the instrument is old NOW, might have been new THEN, so "FWIW, not-much.." from "back in the day" when you could rub two dry field surveyors together and they'd go-on for quite a while as to advantages of Dumpy vs Wye, "etc,"

The purpose of a "level" in surveying isn't so much to assess or alter flatness as it is to run more accurate line, distance, elevation AKA vertical offset up or down.

Back when we had no electronic computers, let alone "GPS" & c., everything had to jump-off "stair-step" style from "Top Benchmarks" that had been established - or had to be added-to, and it was a f**k of a lot of WORK! [1]

EG: MOSTLY I cleared brush so there was a clear shot to the stadia rod I was to then "pilot"!

This might help?

Types of Levels Used for Leveling in Surveying

[1]In the case of Pittsburgh District, Corps of Engineers, proposed mini-dam "Teepleville-Woodcock #5" the TBM was a bronze disk on the concrete front stoop of an old church on high ground. Shoot a level line from that, drop X feet, tenths and hundredth of a foot for Y distance, lather, rinse, repeat for about a mile and a half through light timber and prickly-pear thickets to where the dam was meant to go. Establish a bench mark.

Tie the large number of core drilling's vertical story back to that one bronze disk via the intermediate bespoke benchmark. Do it again, next mini-dam in the plan.

Dead simple. Also Masochistically TEDIOUS!


And then they decided that "mini-dams" for flood-control were not a sustainable concept .... and they were not built.

There are neater gadgets at work, now. And long-since.

That WAS around sixty years ago, and didn't differ much from how the pyramids or the hanging gardens of Babylon had been laid-out.

Now it does. So the gadget on your radar has become basically a museum piece.

See-also "Alidade and plane table."

Alidade - Wikipedia

George Washington's equipment wasn't all that different from ancient Egypt on into the 1970's.

Those, too, have seen massive change as electronics took-over.
 
Probably ought to mention that a naked alignment telescope is not inherently -- in any way -- a leveling instrument. An alignment telescope is perfectly happy pointing straight up, straight down, or anywhere between up and down.

Aside from an adjustable mount, an alignment telescope needs some other instrument to be pointed perpendicular to the direction of local gravity. The two most common of setting instruments is 1) a "striding level" that mechanically fits the cylindrical barrel of the telescope, and 2) a pendulous "leveling mirror" that settles in the direction of local gravity.

FWIW, Brunson made both a striding level and a pendulous leveling mirror.
 
Thermite said:
Dead simple. Also Masochistically TEDIOUS!
That takes me back, not in a good way. In surveying class about '64-'65 one project was a level circuit from the benchmark on campus, down the hill to the river, over a bridge, down the other bank to the next bridge, back across the bridge and back up the bank, then back up the hill to the benchmark. Up and down the hill was a pisser because with the slope you could only get ten or twelve feet before you ran off the top or bottom of the rod. All the sightings go in the log book, and like double entry bookkeeping, when you get back to the start point you should again have zero. We didn't. Crap!! Do it all again but that's another story.
 
TGTool --

Then there was the survey lab instructor who had a couple of "chains" (which were really tape measures, but I guess learning the vocabulary of newer technology was harder way back then) that were deliberately cathwampus . . . One was 99 foot long, the other 101 foot long.

None of the chains were pristine, most having a handful of splices. The pair of shortening-or-lengthing splices were placed in the tapes where they weren't likely to be noticed in the course of the field exercises, but would cause headaches in the form of poor closures.

We did learn to check our tapes before starting our fieldwork, and to plunge and reverse any instrument that could be plunged and reversed.

John
 
.. Up and down the hill was a pisser because with the slope you could only get ten or twelve feet before you ran off the top or bottom of the rod.
This is where I was taught how to "boot" the stadia rod. "Boot it!" as a bellowed order across a stream be from he on the transit, et al, and "BOOTED! the shouted response as I complied ...and he with the log book added the height of a surveyor's boot-top so we got the longer shot and didn't get wet as often! You'd have to know Western Pennsylvania or the like?

All the sightings go in the log book,

In "indelible" pencil, on waterproof paper. So it was good even many years later after swimming a river or working in the rain.

Mistakes had to be left in place as "indelible pencil " was exactly what it sounded like.

Whatever was lined-out was meant to still be readable, new entry following, adjacent. ELSE a page of explanatory notes if an error was not caught until later.

Same as "dead tree" era financial books were kept, back in the hand-written days.

I did say "tedious"?

OTOH, three surveys were "standard" before breaking ground. More went on during the project.

Thankfully.....

Contractors dozer "etc" fleet are roaring down "Redbank Creek" near Pittsburgh dredging, widening, and sloping the banks so next spring's floods, the water gets to go several feet wider for very foot it rises.

Wuddn' yah know it? The team at desk and drawing-board in the Federal building, downtown Pittsburgh screwed the pooch. As the field team, just ahead of the 'dozers going Hell squared for Hades cubed to beat the next season's rain and flooding stakes & string-lines it they can see the neat and tidy reshaping is going to hit one of the abutments of an active highway bridge, not go UNDER it.

Big kerfluffle, they re-calc and alter the drawings, file at a combat speed, rush the new information out to the field.

Only to find Redbank Creek is where it is meant to be, dozers already a loong way past the sneaky walk-about bridge?

And the curve is dead-nuts on the new specs when they take them out of the tubes and check!

They ask Dad how TF he calculated that out in the mud and rain without the Marchant and Monroe-Matic "computers" they used, early/mid 1950's?

He turns over a logbook... and some triangles crayoned onto .... friggin' full-sized 4' X 8' sheets of plywood!

"Same as the Egyptians".

"Scaled it off successive triangles!"

"It DOES help with accuracy if you start at the passage UNDER the bridge ...and work BACK to the existing cut .... eyeballing it, staking as you walk it - so the 'dozers don't go idle @ $100,000 dollars a day penalty because it is the GOVERNMENT's fault!

He had done the math AFTERWARDS ... for no other remaining reason than to call the people behind their penzils, tell them where and HOW they had got it wrong - so as to get the records corrected to match the reality for NEXT maintenance project.

T'was ever thus between desk and field...

... else they'd have gotten the FIRST pyramid at Giza "right", needed no more practice, and gone off to build a chain of more useful shopping malls or brothels.

Think I'm kidding?

Stonehenge was the second go! Same stones.

Whole rig was taken down and MOVED from a previous site!

Damned good job Pennyslvania's highway bridges are not as easily frightened! Traffic jams are bad euf' already!
 








 
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