Thread on GK jet?

Discussion in 'Fettling Forum' started by Murray, Jun 9, 2020.

  1. Murray

    Murray Subscriber

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    I've been trying to measure the thread on an MSR GK jet - but I'm as blind as a bat and not good with thread gauges. The Pitch looks like 1mm to me - diameter measured across the threads 9.32mm (0.367 inches). Thread depth in round figures 0.6mm
    I've looked on the forums but can't find the answer to this question - can anyone help me out with the accurate figures and thread type?
    I would be surprised if it really was a metric thread.
    I have a secret desire to try making one of these on my lathe but I seem to be metrologically challenged...

    Regards
    Murray
     
  2. snwcmpr

    snwcmpr SotM Winner Subscriber

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    It is most likely not a metric thread.
    MSR is a US company.
     
  3. Murray

    Murray Subscriber

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    Agreed - it might be 3/8-24 UNF or something similar, and it would look pretty much the same...
     
  4. Murray

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    Interestingly Penberthy's patent 3,900,281 is available online, but the claim is for the bottle connection and pump only as far as I see at a quick glance
     
  5. snwcmpr

    snwcmpr SotM Winner Subscriber

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    Email MSR.
     
  6. William Ritchie

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    looking at the jet from the Xgk II I have I would have to say a form of straight pipe thread . It is a compression fitting with a 45 degree SAE angle on the face . I Dont have access to my thread gages but I would say 1/8 straight pipe . Wr
     
  7. William Ritchie

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    1/8 Compression would have 24 TPI , 1/8 Straight pipe 27 TPI both are nominally the same diameter but will not thread together .
     
  8. Murray

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    Thanks for that - so many thread forms and standards, so little time.
    The SAE 3/8-24 with the 45 degree seat is certainly pretty close to the my measured dimensions.
     
  9. Murray

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    Thanks William - I rechecked with the thread gauges and by measuring the pitch from the attached image with GIMP and got 24 TPI with the gauges and between 23.5 and 24.5 by scaling the pixel count by the height of the jet. jet.jpg
     
  10. Murray

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    My efforts diligently searching the Forums were rewarded...