Unusual Go-No Go Tool?

[Michael GilliganParticipant @michaelgilligan61133]

Posted by duncan webster on 15/08/2021 00:58:27:

That would be a quartz fibre dosimetry, getting to be old hat when I was regularly visiting Sellafield, and that's a fair few years back. It's all done electronically now.

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That’s not a device with which I am familiar … but curiosity led me to this : **LINK**

https://www.radiation-dosimetry.org/what-is-quartz-fiber-dosimeter-self-indicating-pocket-dosimeters-definition/

MichaelG.

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Edit: __ and this [non pocket-sized] variation on the theme:

http://waywiser.fas.harvard.edu/objects/14362/quartz-fiber-electroscope-dosimeter

Edited By Michael Gilligan on 15/08/2021 06:23:15

[SteviegtrParticipant @steviegtr]

Posted by Michael Gilligan on 15/08/2021 06:15:38:

Posted by duncan webster on 15/08/2021 00:58:27:

That would be a quartz fibre dosimetry, getting to be old hat when I was regularly visiting Sellafield, and that's a fair few years back. It's all done electronically now.

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That’s not a device with which I am familiar … but curiosity led me to this : **LINK**

https://www.radiation-dosimetry.org/what-is-quartz-fiber-dosimeter-self-indicating-pocket-dosimeters-definition/

MichaelG.

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Edit: __ and this [non pocket-sized] variation on the theme:

**LINK**

Edited By Michael Gilligan on 15/08/2021 06:23:15

That's it. You looked down one end, which seemed to have a hair or something fine , which i believed would move across as the Rad got higher.

Steve.

[Michael GilliganParticipant @michaelgilligan61133]

The strange device arrived in today’s post, Martin

Many Thanks

There will now be a [probably long] pause, whilst I try to decipher its function.

MichaelG.

[Michael GilliganParticipant @michaelgilligan61133]

Some minor discoveries already [but no real progress towards identification] …

A) The body and the screw are both made primarily of Ebonite, or similar … suggesting, but not guaranteeing, that they are acting as electrical insulators.

B) The screw can be removed completely, and it carries a brass rod which is tapered to a conical point.

C) There is an insert within the tube, visible through the ‘windows’ … and adjusting the screw changes the gap between this and the cone. This has the ‘feel’ of being a spark-gap, but there doesn’t appear to be a connection to either pole.

D) The pocket clip is plated steel and presumably a ‘bought-in’ commercial item; and it carries the number 5 and the words MADE IN ENGLAND, stamped on the inside of the straight clip.

E) The other metal parts all appear to be brass.

F) The gap in the engraved line above the scale is clearly ‘real’ not just missing paint.

Pictures anon

MichaelG.

[MichaelRParticipant @michaelr]

Michael,

I wish you well with your detective work on the mystery item, one thing that caught my attention is the word Micrographs on the tool body and wondered if that has any bearing on the tool use.

**LINK**

MichaelR

[Michael GilliganParticipant @michaelgilligan61133]

Thanks, Michael

As an amateur microscopist … the word Micrographs was the first thing I commented upon, when Martin posted the question.

I have never seen it used as a unit of measure; which is why I thought it might be the Manufacturer's name [or perhaps the name of a company's department.

If you find anywhere that it is used as a unit, then I would be most grateful

MichaelG.

[Michael GilliganParticipant @michaelgilligan61133]

Some photos to illustrate last night's observations:

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The final one of these shows the conical brass point in situ

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MichaelG.

[Michael GilliganParticipant @michaelgilligan61133]

I have re-formed the peep sight into something approximating its [presumed] original shape, and it now aligns as I would expect.

I have also removed the pocket-clip and the ‘transparent’ plastic sleeve.

Doing this has revealed a spring strip which contacts the brass rod [presumably this makes electrical contact rather than just providing friction : but I’m not yet sure] … There is evidence of this rubbing, in the first photo.

I have not yet been able to separate the brass portion from the main tube … and am wary of applying much force, in case there are other surprises lying in wait.

Time to stop for a while and do some thinking/searching.

… any new ideas as to what it’s for ?

MichaelG.

[Jon LawesParticipant @jonlawes51698]

It's got my mental muscles flexing (both of them!).

I wonder if its something to do with lighting, like setting filaments or gaps between electrodes in an arc lamp?

Spark plug gap setting tool for some unusual plugs? (I'm aware you mentioned this earlier)

I'm thinking a variation on the theme of a gunson device, the window allowing you to see the spark. It would explain why so much of it is of an insulating material.

Just complete stabs in the dark, no background knowledge

 

Edited By Jon Lawes on 19/08/2021 18:51:39

[Jon LawesParticipant @jonlawes51698]

I notice the clip mounts on a brass (or similar) part, does that mean the clip is a part of the circuit being tested?

[Michael GilliganParticipant @michaelgilligan61133]

Thanks for the thoughts, Jon

The word MICROGRAPHS is really niggling me … but I was just thinking about early electron microscopes and the ridiculously high voltages associated with them.

So far as I can see at the moment, there are no ‘terminals’ connecting to the outside world … although, as yet, I don’t know what might be inside that brass ring.

I’m thinking electrostatics … but that seems like an accident waiting to happen.

MichaelG.

[Jon LawesParticipant @jonlawes51698]

I'm not clever enough to do things without google so I did pound companies house etc on the off chance it referred to something other than microscopic photography or similar, as mentioned. A few names bubbled up from the archives but nothing relevant.

I ran it through an image search as well, nothing similar came up. A real puzzler!

[Michael GilliganParticipant @michaelgilligan61133]

Good to have you on board, Jon

MichaelG.

[Michael GilliganParticipant @michaelgilligan61133]

It’s certainly not one of these … but I think we may be heading in the right direction.

**LINK**

https://www.worthpoint.com/worthopedia/vintage-minerallac-pocket-type-1920532728

MichaelG.

[Jon LawesParticipant @jonlawes51698]

http://www.antique-microscopes.com/chemistry/Leitz_hand_spectroscope.htm

The clamp on the end keeps bringing me back to spectroscopes (or even, as a tangent, a method of calibrating them with the go/no-go element), but without an optical element that's rather a bum steer. Maybe it will jog someones memory.

I did see a photo of something similar where a square clamp at the bottom held a very old looking square prism (almost crystaline rather than optical), but I can't find it again now.

[Michael GilliganParticipant @michaelgilligan61133]

My ‘working assumption’ has been that the bent-strip device is a crude version of a viewfinder:

**LINK**

https://kamerastore.com/product/linhof-peep-sight-wire-frame-finder-en/

… and it would certainly function as such.

BUT … as I have no idea how one might use a viewfinder on this gadget, I am happy to entertain the suggestion that it could be a clip to hold a sample.

MichaelG.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Michael Gilligan on 20/08/2021 06:52:29:

[…]

BUT … as I have no idea how one might use a viewfinder on this gadget, I am happy to entertain the suggestion that it could be a clip to hold a sample.

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Having [or so I thought] successfully re-formed the strip slightly, to make the ‘sight’ work properly; it now appears that I have actually deformed it from the shape required for it to function as a pair of electrical contacts for some [as yet unidentified] component under test.

I probed it with the multimeter and discovered that:

• There is no electrical continuity between the two sides
• The square frame is connected to the internal insert
• The ‘peep-hole’ strip is connected to the spring strip which contacts the pointed brass rod
• The Brass ring has no electrical connection with any of these parts

There is surface corrosion on the brass rod, but I am sure that it would be in good electrical contact if it was clean.

So … the moral of the story to date is :

Don’t assume that because it looks like something you know, that’s what it actually is !

MichaelG.

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P.S. __ I remain utterly bewildered by the use of the word MICROGRAPHS, and have no idea what the thing tests … but it’s keeping me amused

[SteviegtrParticipant @steviegtr]

Does either of the 2 fingers or jaws move . I was thinking a part missing that when the bottom was screwed up it closed the jaws. Giving an exact size for an object. If under or say oversize. The marker line would show not go.

Steve.

[SillyOldDufferModerator @sillyoldduffer]

How about a Disappearing Filament Pyrometer?

The peephole and square holder takes a plug-in battery, filament, on/off switch and lens module. Does turning the base knob vary a resistance inside the handle? If so, the temperature of the filament could be altered to determine if furnace is close to correct operating temperature.

I agree 'Micrographs' defies logic!

Dave

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Steviegtr on 20/08/2021 14:37:15:

Does either of the 2 fingers or jaws move . I was thinking a part missing that when the bottom was screwed up it closed the jaws. Giving an exact size for an object. If under or say oversize. The marker line would show not go.

Steve.

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Sorry but No, Steve … no movement except for them being springy … But they are each electrically connected to one of the contacts inside.

All that the screw does is move the pointed brass rod [and the indicator line], so changing the size of the ‘spark gap’

The gadget appears to have no other electrical connection with the outside world … so could it perhaps be that the thing being tested is a source of energy [hopefully not a radioactive source]

Keep the ideas coming, please …

MichaelG.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by SillyOldDuffer on 20/08/2021 14:45:53:

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Does turning the base knob vary a resistance inside the handle?

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No, Dave … it just moves the pointed brass rod and the indicator line

Here, for convenience, is a crop from the photo that I posted before:

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MichaelG.

[Graham MeekParticipant @grahammeek88282]

Hi Michael,

Is the the staining on the brass point similar to the powder from an arc strike?

The reason I ask is that this unit clearly clips onto something with the square portion, and the hole in the other contact rest on another exposed contact area. Both these parts appear to be insulated from each other.

In the view finder there appears to be a small "hair pin" electrode just beneath the clip.

My reasoning is the brass point is wound in until the current jumps the gap, viewed through the view finder. The position of the red line shows if the device is set correctly.

The problem is I don't know what would warrant such a tool in the electrical field. It might well be something to do with power generation. Or possibly capacitor storage capacity.

Regards

Gray,

[Michael GilliganParticipant @michaelgilligan61133]

Many thanks for the input, Gray

Yes, the staining does have that general appearance …

I am hoping to take some detail photos later today.

MichaelG.

[Michael GilliganParticipant @michaelgilligan61133]

As promised :

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MichaelG.

[Martin King 2Participant @martinking2]

Michael,

If the grubby window part will clean up it will transform the item visually!

Just wondering if there are is any small melted pitting on the inside which would support the arc idea? ie sparks?

Martin (who had no idea that this thread would run on so!) Excellent detailed work.

Martin

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