Announcement

Collapse
No announcement yet.

Screwy Situation!!

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Screwy Situation!!

    And why wouldn't it be ? Im putting together a Old Dividing Head and need to find where to buy 12-32 machine screws?? I think also 7/32 - 32 would work and be a couple thou bigger in O/D .It seems these are hard to find as no bolt shop has them? They are to hold a Index Plate to the Face of the Dividing Head, Thanx Mike

  • #2
    Mike

    There a couple of choices 1) make the screws. This depends on your desire to single point them. There should be standards in quite old Machinist handbooks. 2) Carefully drill and tap 1/4-28 and modify the heads of the screws to fit your plates. Either way a nice way to spend some quiet time in the shop.

    Pete

    Comment


    • #3
      Sounds like you have a Brown & Sharpe dividing head.
      They made their own fasteners.
      Oddest thread I ran into on my B&S #13 grinder was
      6-40 thread and 14-24 thread.

      -D
      DZER

      Comment


      • #4
        I just finished looking thru my odd ball die. I would have guessed I would have something that would work, given that I have such as: 3/16-30, 7/64-48, 5/32-36, 9/64-40, 14-40, and maybe another 2 dozen of many "can't live without it" sizes. These things look like they should be drawing social security, like me.

        TC

        Comment


        • #5
          12-32 x ?

          And what type of head?

          Comment


          • #6
            I think Amazon has a 12 32 die for about 16 bucks.

            Comment


            • #7
              These guys list some 12-32 screws:
              https://military-fasteners.com/drill.../thread_qty/32

              Comment


              • #8
                Have you considered that they may be metric?

                M5-0.8 is a few thou larger diameter than #12 but much smaller than 7/32" you mentioned as a possible alternate and the pitches are very close too, 0.8mm = 31.75 TPI.

                Comment


                • #9
                  Originally posted by genea View Post
                  Have you considered that they may be metric?

                  M5-0.8 is a few thou larger diameter than #12 but much smaller than 7/32" you mentioned as a possible alternate and the pitches are very close too, 0.8mm = 31.75 TPI.
                  I went trough this scenario already yesterday (but didn't post anything as it didn't add up.)
                  https://en.wikipedia.org/wiki/Unified_Thread_Standard

                  #12-32 has 5.48mm major diameter so it has about 10% larger diameter than M5. Recommended drill size for tapping #12-32 is 0.188" or 4.77mm, too close to M5 major diameter low tolerance limit 4.83mm
                  https://www.engineersedge.com/hardwa...ead-sizes1.htm

                  Comment


                  • #10
                    The assembly is heat treated. if it was in soft condition I could easily Drill and Tap. On a positive note my stepper system is completed and working, cost some money but well worth it. Now just have to finish brackets and mounting system. Ended up paying a Pro to help me out and well worth it. I learned a lot on this Project. Just a question do yo ufellows finsd posting pictures a real pain in the ass on this Forum? It used to be Photobucket but..they want money ..seems excessive to a Computer Dork like myself as to compared to other sites that have simpler systems to load Photos Thanx mike??

                    Comment


                    • #11
                      What size and type of 12-32 screws do you need?

                      Comment


                      • #12
                        If they are to hold the index plate on they aren't high stress so brass would do. I don't wish to appear mean but if you have managed to get to the point in your machining life of needing a dividing head wouldn't it be time to learn single point threading? Done in brass there would be no risk to the dividing head if they weren't perfect and you would feel so proud having made them yourself.

                        Comment


                        • #13
                          Ah I usually dont make small bolts . Thought maybe could just Buy some. Thanx!!?

                          Comment


                          • #14
                            Originally posted by madman View Post
                            Ah I usually dont make small bolts . Thought maybe could just Buy some. Thanx!!?
                            Why won't you answer my question. asked twice already?

                            What length screws, and what head type, do you need?

                            Answer, and I might have a solution for you.

                            Comment


                            • #15
                              Hi Andy I have been Very Busy, Holidays Xmas Time. Must of Driven over 1400 kms in the Last 3 Days also. Thank you for the Reply. I need a Pan head type Bolt, or even Countersunk as I have made a Plate for the Front of the Dividing head, it is neither counter bored OR Countersunk at this point as i was searching for suitable fasteners.

                              Comment

                              Working...
                              X