Unknown thread standard (italian coffee machine)

Hello everyone!
I restore vintage espresso machines and right now I have one machine with really strange threads, which are used on pipe connections. The
machine was manufactured in Italy in the 50s. Here are some examples:
TPI 20    diameter 14.9mm    = 0.5866" TPI 20    diameter 19.25mm    = 0.7578" TPI 16    diameter 20.25mm    = 0.7972" TPI 16    diameter 22.8mm    = 0.8976" TPI 16    diameter 27.7mm    = 1.0905"
Does anyone know what kind of threads it might be?
Many thanks, Julius
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It's "IBT" standard. (Italian Bastard Thread)
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Yeah... they used that standard on Fiats until the late 1990s.
Then they changed everyting over to Quasi-Metric Standard Hungarian Industrial Threads. (Quasi-metric S.H.I.T.)
LLoyd
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I have a table originally compiled by Andy Pugh that covers about 520 standard threads in the following thread systems and did not get a hit. Good luck!!:
BA = British association. CEI = Cycle Engineers Institute. ADM = Admiralty. M = ISO Metric. Whit = Whitworth. UNF/UNC = Unified national Fine/Coarse. BSF = British Standard Fine. W.INS = Whitworth Instrument. W.Pipe = Whitworth Pipe Thread Brass = Brass thread. PROG = Progress Thread. BSP = British Standard Pipe Thread. WALTH = Waltham Thread PEND = Watch Pendant Thread. GAS = Gas (Brass Pipe) Thread THURY = Swiss Screw Thread. ASME = ASME Thread. HOLTZ= Holtzapfels Threads. LOEW = Loewenhertz Threads. SPARK = Spark Plug Threads. Elgin = Elgin watch screw threads (L = left hand thread) CROWN = Watch crown threads. BUTTON = Watch button threads COND = Steel conduit thread (DIN 40430)
Buerste wrote:

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That means it might be a custom made thread? Thanks for your research Lloyd!! I also have already checked several websites with thread standards and couldn't find anything. But your table seems to include even more standards.
Julius
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That means it might be a custom made thread? Thanks for your research Roy!! I also have already checked several websites with thread standards and couldn't find anything. But your table seems to include even more standards.
Julius
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    --Dollars to donuts some one guy was crankin' out these machines in a shop with a weird lathe and weird feed ratios.
--
"Steamboat Ed" Haas : Imagine what I could do if
Hacking the Trailing Edge! : I knew what I was doing...
  Click to see the full signature.
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On Wed, 15 Jul 2009 02:09:19 -0700 (PDT), Nicht die Bohne

=======While this may not be *THE* answer, it is "A" answer.
During the time period immediatly after WW2 many surplus INCH standard lathes were sent overseas as part of the post-war reconstruction effort.
In many cases the parts these produced were bastard metric/inch as you describe with inch threads but metric diameters/lengths/thread forms, with the inch thread selected as close as possible to the metric size.
Unka' George [George McDuffee] ------------------------------------------- He that will not apply new remedies, must expect new evils: for Time is the greatest innovator: and if Time, of course, alter things to the worse, and wisdom and counsel shall not alter them to the better, what shall be the end?
Francis Bacon (1561-1626), English philosopher, essayist, statesman. Essays, "Of Innovations" (1597-1625).
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On Jul 15, 10:41am, F. George McDuffee <gmcduf...@mcduffee- associates.us> wrote:> In many cases the parts these produced were bastard metric/inch

Yes. Consider BA - used by the Brits for years but actually metric!
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wrote:

Hand-chased by some guy on a treadle lathe? You don't NEED dies or taps to cut threads, they do help to make interchangeable parts, though. If it's got that hand-made, one-off look, it might have been done that way.
Stan
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Wed, 15 Jul 2009 02:09:19 -0700 (PDT), Nicht die Bohne, snipped-for-privacy@googlemail.com wrote:

BSPP is fairly common in espresso machines. I imagine you've already checked that? (Sorry, I don't have my Machinery's Handbook at hand)
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