Tapping Holes in White Metal

Discussion in 'FAQs' started by DWP, Nov 2, 2004.

  1. DWP

    DWP Member

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    I am working on a 20 ton shay with keystone parts.
    I need to tap some 0-90 threads if I can see that small.
    Any ideas on what to use to keep the tap from clogging up?
    If not, any ideas on attachind the tender to the frame so I can remove it later.
    Thanks
    Dave
  2. Glen Haasdyk

    Glen Haasdyk Active Member

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    White metal is very soft but it should tap fairly easily. The idea is to turn the tap 1/2 turn in, then turn 1/4 out. This will break-off the metal shavings that tend to clog up the tap. winding the tap in all the way without 'back-turning' it is a sure way to break a tap.
  3. Dick Rasmussen

    Dick Rasmussen New Member

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    I agree with Glenn, and you might want to use a thin lubricant( kerosene& oil I.E.) with a quality tap. Good luck. Dick R.
  4. N Gauger

    N Gauger 1:20.3 Train Addict

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    I've actually done this :) :) Not that small though.

    The basic rules are what has already been stated:

    1/2 turn in (Slow) 1/4 turn out - then when the teeth grab again, "repeat"

    Also - Use 3-in-1 oil or any other "light oil" and use a bunch!!! Don't spare it!! If the oil drips out when you pull (turn out) 1/4 - then it's fine!!! After every 4 turns (One Complete revoultion) take the tap out & drip a drop or 2 of oil down the hole and clean off any "Shavings" from the tap. Do this "Every complete revolution"!!

    Last thing: All "good Quality" taps have the size of the tap on it as well as a drill size. Get a new, sharp, drill in this size & use it slowly as above, same thing as above - Oil Oil Oil!!!

    If you take your time & use the right, new, sharp tools, this should be easy!!!!

    Best of luck!!!!
  5. jim currie

    jim currie Active Member

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    in using taps that small in soft metal is hard it tends to clog tap i use ith 1/8 turn and back a1/4 and remove tap fron hole every 1/2 turn and blow chips out of hole i use wd40 in spray can for lub.
  6. N Gauger

    N Gauger 1:20.3 Train Addict

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    Since I've never done tapping this small - I'd side with Jim :) :D :)

    Err on the side of caution!!!!!
  7. sumpter250

    sumpter250 multiscale modelbuilder

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    I've heard that applying bees wax to the tap will help the soft metal flakes to fall off the tap. Not as messy as oil.
    Pete
  8. DWP

    DWP Member

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    Thanks for the help.
    Al at B & F Hobbies suggested to make a new
    main frame out of brass. The frame that came with the kit is white metal. After cutting a hole for the gear box there is not a lot of metal left for support. So fo now I am in the process of cutting a new brass base.
    DP.