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What is this 100 year-old screw thread?

Rich L

Hot Rolled
Joined
Sep 24, 2006
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Colorado
this is a coincidental post not dissimilar to the one posted by LordGimmick ...

I'm restoring a 100+ year-old Swiss-made (Lienhard) brocading machine and it is full of machine screws that have a mysterious diameter and pitch scheme. I've posted a picture of one of them, and there are many of these in the machine, to show the dimensions. I hope the picture comes out big enough ...

Here they are:
Extrapolated V-thread major diameter = ~.230 in (5.84 mm)
Actual major diameter = .222 in (5.64 mm)
pitch = ~ 22.94 tpi (1.11mm)

I've looked at all the thread tables I can find: metric, BA, BSW, BSF, BS ISO, Thury, etc. and, of course the Unified tables, and unless I've missed something, nothing matches. I suspect this screw thread scheme pre-dates all of the tables I have.

Many of the screws are damaged and need replacement so I'll need to find some or make them if I must.

Has anyone got a hint on what scheme these may fall under?

I predict a response or two: "Make 'em!" :) Even if I can't find them and have to make them, I'd like to adhere to a standard that suits it's origin if possible. Many of them have long engagements of 3/4 inch so an approximate standard has to be pretty close.

Cheers,
Rich
screw thread.jpg
 
Today we reap the rewards of a wide range of technical standards that ensure among many other things ready replacement and interchangeability of threaded fasteners (Metric and Unified).

A century ago, it was a different story when manufacturers vied with one another to ensure only their stuff would fit their stuff. PITA and your machine appears to be a legacy of that era. I don't even have a suggestion how that particular set of fastener parameters would be called out in a manufacturer's drawing. PITA.

Looks like if you wish to repair and replace component parts to manufacturer's specs as when new or a museum restoration you will have to make fasteners from scratch and the taps to refurbish the holes. PITA
 
Exactly what I was afraid of: "Make 'em" = PITA. Fortunately, all the holes are still good. It's the heads that are in really bad shape after 100 years worth of assembly and disassembly with the wrong tools. I may just EDM hex or torx holes to keep them in play.

... ...

A century ago, it was a different story when manufacturers vied with one another to ensure only their stuff would fit their stuff. PITA and your machine appears to be a legacy of that era. I don't even have a suggestion how that particular set of fastener parameters would be called out in a manufacturer's drawing. PITA.

Looks like if you wish to repair and replace component parts to manufacturer's specs as when new or a museum restoration you will have to make fasteners from scratch and the taps to refurbish the holes. PITA
 
this is a coincidental post not dissimilar to the one posted by LordGimmick ...

Here they are:
Extrapolated V-thread major diameter = ~.230 in (5.84 mm)
Actual major diameter = .222 in (5.64 mm)
pitch = ~ 22.94 tpi (1.11mm)

Has anyone got a hint on what scheme these may fall under?

Cheers,
Rich
View attachment 201893

It's a metric lead 10/9 = 1.11111111... etc...

Either the distance (1cm) in 9 turns is important or the timing of 9 turns is important.

BTW every screw metric is a lead, imperial leads are much harder to sort out but they were used for the same purpose I mentioned above (IE. 60 threads in 5 foot).

Good luck,
Matt

On edit... you can make a screw easily for that fraction (any length standard) but it's seriously discouraged with metric stuff. They just did it way back when...
 
Last edited:
Looks like if you wish to repair and replace component parts to manufacturer's specs as when new or a museum restoration you will have to make fasteners from scratch and the taps to refurbish the holes. PITA

Indubitably. Too lazy to go see what even a OLD machinery's handbook lists, but just as a wake-up call?

Some time in the early 1960's "American Machinist" ran a series of their famous, and often quite USEFUL, 'tear out' yellow-ish pages on screw thread standards.

I saved it for many years.

Best of my recollection there were one hundred and twenty one of those standards documented.

The 'bad news' is that even so, not one of those has the least chance of matching this old Swiss-made machine.

It was probably made when one of several possible 'ligne' measures - neither inch nor metric, nor Persian, nor Russian - was the measurement basis. Depending on WHERE in Switzerland it was made? Might start with the OLD "French" ligne?

In any case, you'll first have to reverse engineer and document your OWN 'standard', derived from measurements and SWAGs as to wear effects. Only THEN will you be able to repeatably and usefully fab to it.

Not impossible. Humans made the originals, after all.

Just gawdawful TEDIOUS, is all.
 
You obviously have a non standard thread and will probably have to make your own replacements. In measuring it, you should concentrate on the pitch diameter, not the present OD that you can measure. If you get the thread pitch and the pitch diameter correct then you can just slowly trim the OD until it fits in the hole as the "flat" on the crests of the thread you cut will be the obvious source of interference. But if you go by the present OD and cut the thread deep enough to fit, then it may be a very loose fit as the pitch diameter may be too small. This would reduce the strength of the joint. By getting the pitch diameter correct, you can avoid this problem.
 
I have seen a few antiques with threads hat fit nothing I was able to conjure up! And,I mean antiques that were not SO OLD that they should have been part of some standardized thread system somewhere! I was asked to make a screw for a high class double barrel shotgun. French,made in the 20's or 30's. Possibly post war,I can't say. It fired modern shells.The barrels pulled forward enough for the shells to drop out onto the receiver. Beautiful engraving. I think the name started with a P.

That damned thread was impossible to get right. But,I got the thread CLOSE enough that it would screw in for 2 or 3 turns. After that,the only thing I could do was keep tightening and loosening the blasted screw till it was tight enough,burnishing them together. Fortunately,the screw threaded into the trigger guard,which was HARDENED on this gun.

The job was a free favor,but the only pay I got out of it was getting mad at the French!!!:)

In addition to lathes,I have a BUNCH of antique screw plates that I can also use if all else fails.

I work with very old(usually 18th. C.) antiques all the time. I have never not been able to make a screw that would fit. A lot were left hand,too. But,that French shotgun(can't recall the name)beat all of them!

P.S.,Monarchist: I recently restored an 18th. C. French tailor's folding rule. Made of walrus tusk(the rule was). It folded into about 3" long sections. The grads were in lignes. A ligne seemed( IIRC )to be ABOUT 1 1/8". It was actually the little ray skin covered case I repaired.That ray skin must have been skived down to nearly .001" thick! You could see through it! Whoever skived that ray skin was indeed a past master!!
 
Today we reap the rewards of a wide range of technical standards that ensure among many other things ready replacement and interchangeability of threaded fasteners (Metric and Unified).

A century ago, it was a different story when manufacturers vied with one another to ensure only their stuff would fit their stuff. PITA and your machine appears to be a legacy of that era. I don't even have a suggestion how that particular set of fastener parameters would be called out in a manufacturer's drawing. PITA.

Looks like if you wish to repair and replace component parts to manufacturer's specs as when new or a museum restoration you will have to make fasteners from scratch and the taps to refurbish the holes. PITA

And even if you manage to identify the thread as a 1890 french standard left-handed womens bicycle rear wheel spoke tread you probably still have to make it yourself. :D

Even BSF cap head screws are pita to find nowadays.
 
Somehow my my thanks to all who replied got lost in the movement of this thread from "General" to "Antique Machinery and History. Again, thanks.

The machine was made in La Chaux-de-Fonds, Switzerland in 1904, bordering right on France. Brocading machines are quite the contraptions. Lienhard made many machines in those days: rose engines, straight line engines, brocading engines and variants probably totaling in the hundreds. They must have had a solid assembly line making those screws... or they bought them from somebody. I should go over there and search for a leftover cache :) . It would be a nice trip.

Cheers,
Rich
 
If it was me and there was space for it I'd drill and tap for the next standard size up wherever possible. make it an easy one for you to procure.
 
Might start with the OLD "French" ligne?

According to Google the French ligne is said to be 2.25583 mm which, given the period in question, is a statement of meaninglessly preposterous accuracy. Especially as the ligne is a divide down system being 1/12 of the root French inch which in turn is 1/12 th of the French foot with both subject to regional variations.

Given reasonable tolerances for the era its likely that your 1.11 pitch, 5.64 mm OD screw was made 1/2 ligne pitch by 5 ligne diameter. Extrapolated OD doesn't really apply here.

Clive
 
Rich, the photo is not sharp which is a pity, you have a thread projector there.
Would you mind making a fresh picture from a tripod or something to bring out
the flank angle, big? One to two crests is what you want to see, enlarge that thing.

If it’s not 60 or 55 degrees, we’re a step further. If you could confirm it’s 53°08' we knew it’s the Löwenherz 7 mm.

Lowenherz-Gewinde
 
..the only pay I got out of it was getting mad at the French!!!:)
Funny thing is.. if a former possession of a "French" double 12 is any guide, that may have been misplaced anger.

A major retailer called "Le Arquebusier" in Paris was for long years prior to War Two house-branding and selling rather nice shotguns.. that were actually made in BELGIUM.

Even then, some of those had Bohler barrels made in GERMANY, and the proof-marks of two, if not all three countries if one but knew where to look, and where to "look up" the ever-so-tiny "artwork" of the stamping.

:)

Not that is was all that "one way", either. For many years AFTER War Two, most Walther pistols were made in France by Manhurin.
 
Somehow my my thanks to all who replied got lost in the movement of this thread from "General" to "Antique Machinery and History. Again, thanks.

The machine was made in La Chaux-de-Fonds, Switzerland in 1904, bordering right on France. Brocading machines are quite the contraptions. Lienhard made many machines in those days: rose engines, straight line engines, brocading engines and variants probably totaling in the hundreds. They must have had a solid assembly line making those screws... or they bought them from somebody. I should go over there and search for a leftover cache :) . It would be a nice trip.

Cheers,
Rich

Hot bed of industry La Chaux-de-Fonds. That whole 'French Swiss' valley is full of interesting places, and breeding ground of quite a few downright legendary individual craftsman, as well as their mini-factories.

Louis Chevrolet, to name one who chose to leave home to work in things larger than timepieces.

Always though it a good measure of immigrant-built America, the phrase:

"As American as baseball, hot dogs, apple pie, and Chevrolet."

And not even one of those actually 'home grown' by creators who were themselves born on the North American Continent..

:)
 
It was actually the little ray skin covered case I repaired.That ray skin must have been skived down to nearly .001" thick! You could see through it! Whoever skived that ray skin was indeed a past master!!

Next time a trip to England is on your dance card, go by way of BWI and take a day or three stopever in Iceland. I used to do it often when our bean-counters dropped Biz Class air fare even for Director-level folks. Virginia Law of the era said folks had to be given at least a 20-minute break after six hours, I call cattle -class 'work', and the cheap-seats direct flight exceeded the time. Soooo so I broke the trip in two with a free overnight at Hotel Esja, and for twelve bucks less that direct economy, net-net.
So much for 'work to rule' and cheaper, too. For that part.

Bean-counters eventually relented when the math of a one-day out-and-back by Pan Am biz-class redeye, free upgrade to First Class on my "platinum" miles-count, no hotel required, one cheap C&W in-house pub-grub meal had turned into ... a 3 to 4 day exercise with meals and lodging at The Strand or Dorchester Hotel .... sort of overwhelming the knee-jerk air-fare savings, as it were..

:)

Meanwhile.. Iceland..

Over their looong history, the population had been near-as dammit wiped out - twice, IIRC - by lethal gas in volcanic eruptions. That killed such livestock as they had as well. So.. desperate Icelandic folks found a way to make FOOTWEAR out of fish and ray skins instead of cow, goat, or sheep hides.

Interesting place, and SMALL museums, so it doesn't take long to tour most of it. Most times, I'd rent a car as well.

Highly recommended 'at least once', Iceland is.
 
"A Compilation of Thread Size Information."

Probably the most complete index of thread, both English and Metric, available in one place.

The spreadsheet starts out kind of slow, but in four or five pages you make it up into the more common "standard sizes."

And information is provided in english for metric threads and metric for english threads.

Hard to beat what is contained here - including the various machine screw sizes (ASME Threads)

http://webcache.googleusercontent.c...BSgXK4J:www.watchman.dsl.pipex.com/thread.xls

Joe in NH
 








 
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