About taps...
Close
Login to Your Account
Results 1 to 11 of 11

Thread: About taps...

  1. #1
    Join Date
    Sep 2010
    Location
    Anchorage, Alaska, USA
    Posts
    628
    Post Thanks / Like
    Likes (Given)
    229
    Likes (Received)
    122

    Default About taps...

    Hi Guys!
    Ok, I been at it for over 30 years.
    But, I noticed a detail I have never properly addressed.
    Taps.
    I have generally... used hand-taps from day one.
    I kind'a preferred the 2 flute plug tap.. they seemed to do well.
    But then there is spiral, and again spiral..
    I usually tap dead holes, so tapers are mostly not in the picture.
    So... a lot of these taps I have qualify as spiral. I mean with a bit of a negative grind at the tip.
    But, I watched this video from NYC CNC and he used the taps that were spiral.. I mean they look like a cork-screw... complete helical relief grind.
    So I had one in 1/2-13 and ran it... was amazed.
    It pulled the chip out of the top of the hole.
    Now, honestly, I am in favor of form taps these days.
    But, I'd like to hear your thoughts on tap selection for production CNC operations.
    Again... my many thanks!!!
    Mark

  2. #2
    Join Date
    Jun 2015
    Country
    UNITED STATES
    State/Province
    Minnesota
    Posts
    202
    Post Thanks / Like
    Likes (Given)
    6
    Likes (Received)
    67

    Default

    Hi Mark,

    My 2 cents.

    Blind holes - form taps are great. That spiral flute tap you spoke of works great in blind holes as you noticed, but in production I find that unless you have a powerful coolant stream going on them, they don't always release the chip. Meaning I would have a hard time walking away from the machine if it was going to tap a dozen or two holes or more.

    Through holes I'll stick with spiral point. 2 flute on the smaller diameters, and never more than three. I also like the DIN length ANSI shank taps. I find the extra length comes in handy.

    I wouldn't consider anything under three flute a hand tap. Two flutes are not that easy to get started straight. You know what does work great for hand tapping, is the spiral flute taps we've been talking about. They start real easy and are easy to get straight. Plus they tend to cut easy.

    Holes where you want usable thread all the way to the bottom I'l go thread milling. Plus a large diameters when there are only a few or limited torque to drive a big tap.

    Dave

  3. #3
    Join Date
    May 2011
    Country
    UNITED STATES
    State/Province
    New Jersey
    Posts
    1,921
    Post Thanks / Like
    Likes (Given)
    173
    Likes (Received)
    1042

    Default

    Quote Originally Posted by snowshooze View Post
    Hi Guys!
    Ok, I been at it for over 30 years.
    But, I noticed a detail I have never properly addressed.
    Taps.
    I have generally... used hand-taps from day one.
    I kind'a preferred the 2 flute plug tap.. they seemed to do well.
    But then there is spiral, and again spiral..
    I usually tap dead holes, so tapers are mostly not in the picture.
    So... a lot of these taps I have qualify as spiral. I mean with a bit of a negative grind at the tip.
    But, I watched this video from NYC CNC and he used the taps that were spiral.. I mean they look like a cork-screw... complete helical relief grind.
    So I had one in 1/2-13 and ran it... was amazed.
    It pulled the chip out of the top of the hole.
    Now, honestly, I am in favor of form taps these days.
    But, I'd like to hear your thoughts on tap selection for production CNC operations.
    Again... my many thanks!!!
    Mark
    Ugh why would you watch that hack...

    I like spiral taps but find they can be a bit easier to break.

  4. Likes digger doug, Mtndew liked this post
  5. #4
    Join Date
    Oct 2010
    Country
    UNITED STATES
    State/Province
    Oregon
    Posts
    5,032
    Post Thanks / Like
    Likes (Given)
    4220
    Likes (Received)
    1812

    Default

    The ones with "a bit of a negative grind" are spiral point taps, often called gun taps.

    The ones with spiral flutes are, surprise, spiral flute taps.

    Spiral point taps are great for through holes. They shoot a continuous chip out the bottom of the hole. I will even use them by hand on some blind holes.

    Spiral flute taps, as you found, do a good job of clearing the chip at the top of the hole. Like plastikdreams, I find them a bit fragile, especially in smaller sizes.

  6. Likes Bobw liked this post
  7. #5
    Join Date
    Oct 2005
    Country
    UNITED STATES
    State/Province
    Pennsylvania
    Posts
    14,546
    Post Thanks / Like

    Default

    Quote Originally Posted by plastikdreams View Post
    Ugh why would you watch that hack...

    I like spiral taps but find they can be a bit easier to break.
    .....and wilton don't make extraction fingers to fit them....

  8. #6
    Join Date
    Dec 2014
    Country
    CANADA
    State/Province
    British Columbia
    Posts
    1,275
    Post Thanks / Like
    Likes (Given)
    361
    Likes (Received)
    581

    Default

    Quote Originally Posted by digger doug View Post
    .....and wilton don't make extraction fingers to fit them....
    Don’t fit form taps either

    Spiral points push the chip ahead, spiral flutes pull the chips out, form taps form the threads through pure force of will.

  9. Likes digger doug liked this post
  10. #7
    Join Date
    Feb 2019
    Country
    CROATIA
    Posts
    22
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    0

    Default

    Been doing a lot tapping and I learned one thing. There is no rule. Had tap that break in first hole and had tap that did 100+ holes before break. Now i tap on machine but only small depth and finish it by hands. Spiral flutes ofc. And just few days ago we bought machine for tapping which seems great so far

  11. #8
    Join Date
    Jun 2012
    Location
    Michigan
    Posts
    4,577
    Post Thanks / Like
    Likes (Given)
    4185
    Likes (Received)
    2737

    Default

    Spiral flute taps are great.....until you need to tap a deep hole on the cnc.

  12. #9
    Join Date
    May 2009
    Location
    Canandaigua, NY, USA
    Posts
    2,825
    Post Thanks / Like
    Likes (Given)
    135
    Likes (Received)
    1235

    Default

    No CNC experience here but I like form taps wherever I can use them, spiral flute taps for aluminum and spiral point taps for everything else. If they never made another "hand tap" or 3-flute tap, I'd never notice.

  13. #10
    Join Date
    Sep 2007
    Country
    UNITED STATES
    State/Province
    Washington
    Posts
    5,126
    Post Thanks / Like
    Likes (Given)
    177
    Likes (Received)
    1475

    Default

    I've tapped like a quarter million holes in the VMC in the last 2.5 years. Thru, blind, tiny, big-ish. I use form taps as a starting point for everything up to ~3/8". 95% of those 1/4M holes were done with form taps. Sometimes, I cannot get a form tap to behave. Sometimes it's hard to get the hole size just right, so that the minor comes out right. Sometimes even when the hole size is right, the minor is too small (material didn't flow as intended and left ragged crests). Then I go to a cut tap.

    Spiral point are generally great if it's a thru hole, IF you have sufficient daylight under the hole as spiral point taps have a pretty long lead-in and need a lot of breakthrough.

    Spiral flute are great for shallow blind holes, but deeper blind holes can be trouble if the swarf packs up in the flutes. The spiral flute tap only does its nice swarf extraction trick if the swarf stays in one piece. If it breaks mid-cycle, the next piece can jam into the previous piece and then you have a mess. I have peck-tapped with spiral flute and that works fine. I will try to program a generous retract so the coolant blast has more time to knock the swarf off the tap before it goes back in.

    Regards.

    Mike

  14. Likes sfriedberg liked this post
  15. #11
    Join Date
    Sep 2010
    Location
    Anchorage, Alaska, USA
    Posts
    628
    Post Thanks / Like
    Likes (Given)
    229
    Likes (Received)
    122

    Default

    Wow guys...
    Awesome.
    But, my observation is..
    There ain't a clear answer.
    I can accept that.
    Thanks for all the in-put!
    Mark


Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •