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Jig Transits / Optical tooling

I use an optical level from time to time. Architectural /building erection etc..
I've got a nice K&E alignment scope and illuminated target. But have only played with it for my own purposes (vis. lathe alignment). Professionally, I've implemented similar optical testing devices for confirmation of optical wedge for the most demanding applications on this planet and others ;-).
 
alignment

Anybody here use Jig transits, alignment scopes, ect?

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I have used jig transits and optical level collimator for paper and film conveyance
machines. typically 60 to 120" wide film has some stretch ability and changes length
as it dries so if uneven drying one side of web can be tighter than another
.
typically alignment is .005" per 60" although if conveyance rollers are farther apart
the alignment tolerance can often tolerance .010" or more.
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after running field calibration tests to make sure jig transit calibration is in normal
range typically a crosshair width. reticle width typically 4 to 10 arc seconds.
at 100 feet a 10 arc second wide cross hair is .060" wide, 5 arc second .030" wide
heat waves at distances over 50 feet the air can shimmer like looking far distances
in a desert or highway on a hot summer day. also structural steel building columns
against a outside wall on a hot sunny day the columns can grow .030" longer over
a 6 hour period. just saying holding repeatable tolerances there are many variables.
I have even seen floor points on either side of a floor expansion joint side shift
considerable amounts as temperature changes
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leveling machinery not only temperature changes but a floor can easily go down if
a fork truck is parked nearby. as machine sections are stacked on top of another
the weight can cause machine base to go down unevenly. especially if machine is
not centered on structural steel supporting floor. optically levels a peg test
is used to check calibration of level
.
dial indicators and precision spirit levels are normally used for short range
alignment especially 40" or less. optical more for long range alignment. sometimes
plumb bobs from a roller 10 feet above are put in cups of water to steady and
the plumb bobs strings are optically shot. I used industrial sewing thread for
string or fishing line. this is similar to drill holes down into a tunnel to check
tunnel straightness. if tunneling underground it would be easy to slowly drift far
off course unless tunnel drilling progress is checked periodically. obviously if
100 to 500 feet off course per mile that could be a problem. optics and air shimmer
there are limits to alignment
 
Anybody here use Jig transits, alignment scopes, ect?

Optical tooling such as you mention is one group of items in "the toolbox" that I sometimes use for opto-mechanical purposes. What is your intent and/or application? Inquiring minds would like to know, as you can see.
 
I use a " Toolmakers microscope" in some applications of machining or surface plate applications, when I worked as a machine repairman/ rebuilder I applied optics for checking machine alignment, nothing beats magnifacation to reveal problems.
 
I have Taylor & Hobsons book " Optical Alignment"and noticed they favor the plumb line method, I never used that with optics but rather aligning paper mill rolls with direct measurement, when optics became more available the switch went to optical scales and transits. Thread for commercial sewing is available in nylon ans polyester with sixty pound tensile strength and its great as a wire alignment substitute, and makes a very good straight line.
 
I am a retired Millwright who doesn't fish or hunt, so instead of boats, snowmobiles, motorcycles, I collect K & E
and have interests in optics, ans surveying.
I also teach Hand Scraping to hobby machinists who pass time doing what I did as work as a hobby, it keeps my 75 year old mind active
 
I have an alignment scope as well but without the autocollimation recticle, I am working on a mount and target
my scope has no built in micrometers so the target has to be adjustable, I have a K&E lateral adjuster with a verneer scale and very fine adjustment.
 
John and Company --

Yes, the "gizmo on the end" is a parallel-plate micrometer. It is, in essence, a thick optically-flat glass parallel mounted on a pivot. When the parallel surfaces are perpendicular to the telescope line of sight, the entering and exiting lines of sight are coincident; when the parallel is tilted, the entering and exiting lines of sights are parallel, but offset in a direction that is perpendicular to 1) both lines of sight, and 2) the axis around which the parallel is tilted.

When the telescope line(s) of sight are precisely horizontal, and the parallel-plate tilting axis is parallel to the telescope tilting axis, the telescope line of sight displaces vertically; to have the displaced line of sight displace horizontally, the parallel-plate tilting axis must be in the plane defined by plunging the telescope around its tilting axis.

I've not seen a K+E parallel-plate micrometer that has any sort of mechanical indexing around the end of the telescope barrel to constrain the parallel-plate tilting axis to be close-enough-to-parallel-or-perpendicular to the telescope tilting axis. In the absence of such an indexing constraint, it is necessary to adjust the line-of-sight displacement direction before making measurements using the micrometer. This is done by checking for line-of-sight displacement at both ends of the micrometer scale, and rotating the micrometer on the telescope to minimize line-of-sight displacement in the UNwanted direction.

For what it's worth, Brunson make conceptually-similar optical micrometers, but with a different type of linkage between the parallel-plate axis and the micrometer dial. The K+E micrometer dial graduations are linear, which allowed use of a vernier scale; the Brunson micrometer dial graduations are non-linear, which precludes use of a vernier scale. Personally, I regard the vernier scale as "marketing eyewash".

I do prefer K+E's use of a white-background micrometer dial to Brunson's silvery background.

John
 
Another oddity in the collection is similar to a compound rest on a lathe, but fits on top of tripod under transit. Maybe this does things similar to the "gizmo"
 
That piece is called a "lateral adjuster" or "lateral slide". It is used to tweak the location of a jig transit or linescope to the same vertical plane as a pair of reference targets, a spindle axis, or a bore centerline (amongst other things). A pair of lateral slides are used when a jig transit must be positioned directly over some particular point, in which case the slide axes are typically perpendicular to each other.

There are cases where it is necessary to location a jig transit at the intersection of two different target planes that are not orthogonal. In such cases, the slide axes are adjusted to be perpendicular to the individual target planes.

There are several different varieties of lateral slide, with operating ranges ranging from about an inch to nearly a foot. The longer ones usually have an adjustment system along the lines of the moving jaw of an old-fashion vernier caliper, while the far-more-common shorter ones generally use some form of lead screw.

Brunson's early slides were built around a South Bend Lathe compound. An internally-threaded ring having a topside bore to take the South Bend conical dovetail held the slide to the instrument stand, while a male thread ring screwed to a custom T-nut secured a jig transit to the top of the slide. Later generations of the Brunson slides did away with the T-slot and replaced the ball-crank handle and graduated collar with a plain knurled knob.

K+E made a much more elegant lateral slide, using a tapered gib, a ground-acme-thread leadscrew mounted with a pair of ball bearings, and a large, clearly-graduated collar. Of course, the K+E slides cost a bit more than twice the price of the Brunson slides . . .

Any lateral slide used under an optical tooling instrument needed to be as close to rock-solid-stable as possible. Achieving this stability required tightening the slide gibs far, far tighter than would be done using the same slide as a lathe compound rest.

The fit-and-finish of the sliding surfaces of the Brunson slides made it downright difficult to achieve the requisite stability without setting the gibs so tight that operating the slide required super-human grip. I found that disassembling the slides, "sandpaper lapping" the gib surfaces, and lapping the sliding-dovetail surfaces of the slide body with Timesaver compound made a world of difference in the operability of the Brunson slides.

Both Brunson and K+E slides needed a thin film of grease on their sliding surfaces. My grease of choice was a Castrol wheel bearing and chassis grease that met the NLGI GC-LB specification. Light amber color and mild scent.

In any case, the lateral slide was used only to position the instrument, not as a measuring instrument. The slides simply weren't capable of holding the instruments' other five degrees of freedom stationary while translating.

John

Edited to add that, for me, the desired snugness of a Brunson lateral slide gib is achieved -- after disassembling, chasing the tapped holes for the gib screws, cleaning, greasing, and reassembling the slide -- by positioning the slide so that the gib is fully supported by the male dovetail and then torquing the gib screws as tight as I can get them when gripping the hex driver between the pads of my thumb and forefinger. Grab only the portion of the driver that's in line with the screw, don't even think about grabbing the bent portion of the driver.

I carried a 3/32 inch driver removed from a "pocketknife" set of drivers on my keyring for this purpose, and always 1) removed the driver from the keyring to use it, and 2) never used the loop end as a wingnut.
 








 
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