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thread pitch question

daleice
daleice Member Posts: 2
what is the thread pitch on an 1-1/4" tailpiece? It seems like it might be 27 threads per inch where it screws into lave drain section. thanks

Comments

  • Intplm.
    Intplm. Member Posts: 1,880
    Depends on the material.

    I'm assuming you are asking about brass or chrome plated brass fine thread on tubular pipe sizes.

    Some plastics have a different pipe thread on there tailpieces.

    Curious. Why do you want to know?
  • daleice
    daleice Member Posts: 2
    yes,brass. Trying to figure what thread pitch it is. I think its 1-1/4-27 but its not ever listed in descriptions and nowhere else on the web...
  • hot_rod
    hot_rod Member Posts: 22,018
    A thread pitch gauge would give you an answer. I don't think it is the same thread as a 1-1/4 fine thread bolt 1-1/4- 18?
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Intplm.
    Intplm. Member Posts: 1,880
    daleice said:

    yes,brass. Trying to figure what thread pitch it is. I think its 1-1/4-27 but its not ever listed in descriptions and nowhere else on the web...

    A long time ago I tried to find out too. I don't recall why.
    I remember the only thread chart I could find (and still today) is that of the common pipe thread.

    I'm curious as to why you want to know. Are you planning on threading with this type of thread yourself?
  • Pumpguy
    Pumpguy Member Posts: 645
    Can't answer your specific question, but if you don't have a thread pitch gauge but do have an assortment of fine thread pitch taps, you can use those just as you would use a thread pitch gauge.
    Dennis Pataki. Former Service Manager and Heating Pump Product Manager for Nash Engineering Company. Phone: 1-888 853 9963
    Website: www.nashjenningspumps.com

    The first step in solving any problem is TO IDENTIFY THE PROBLEM.
  • mattmia2
    mattmia2 Member Posts: 9,572
    You can measure it with a micrometer of caliper and calculate it too. It is best to measure several and divide to reduce the measurement error. Measure peak to peak or valley to valley, divide by the number measured and invert and it will give you the number of threads per inch.
    CLamb
  • Joe_Dunham
    Joe_Dunham Member Posts: 52
    1 1/4" NPT has 11 1/2 TPR, and I think an 1 1/4" slip nut will screw onto an 1 1/4" nipple perfct so it may be 11 1/2
  • hot_rod
    hot_rod Member Posts: 22,018
    I get 27 tpi, 1.25 OD
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • mattmia2
    mattmia2 Member Posts: 9,572
    What are those fancy numbers on your caliper, where's the vernier scale...
  • hot_rod
    hot_rod Member Posts: 22,018
    > @mattmia2 said:
    > What are those fancy numbers on your caliper, where's the vernier scale...
    I have a few analog calipers, I like these digital to measure and convert metric parts quickly, with the push of a button🔩
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    mattmia2
  • jumper
    jumper Member Posts: 2,226
    Happy somebody invented screw idea but variations are cuckoo.
    During lockdown I played with ballpoint pens. There are at least two varieties of Cross type refills. NOT interchangeable.
  • Joe_Dunham
    Joe_Dunham Member Posts: 52
    oh the tail piece thought you meant the slip fittings.