507,870 active members
3,065 visitors online
Register for free
Login
Results 1 to 8 of 8
  1. #1
    Registered
    Join Date
    Mar 2009
    Posts
    1873

    Well, I did it.

    Yesterday I set up a new job that was supposed to get an 8-32 hole tapped 5/8 deep and wouldn’t ya know it, after all the smack I written about tapping small holes, I was using a spiral flute cutting tap and I busted the dang tap on the first hole. I hadn’t broken a tap in 6 or 7 years before that.

    I switched to a form tap and ran the rest of the 125 piece order with no problem.

  2. #2
    Registered
    Join Date
    Dec 2009
    Posts
    451

    Re: Well, I did it.

    Don't you hate it when stuff like that happens. It's like we put the big whammy on ourselves by talking up a good game. I've lost count of all the times I've done this to myself.

    MetalShavings.

  3. #3
    Registered
    Join Date
    May 2008
    Posts
    620

    Re: Well, I did it.

    Quote Originally Posted by Steve Seebold View Post
    Yesterday I set up a new job that was supposed to get an 8-32 hole tapped 5/8 deep and wouldn’t ya know it, after all the smack I written about tapping small holes, I was using a spiral flute cutting tap and I busted the dang tap on the first hole. I hadn’t broken a tap in 6 or 7 years before that.

    I switched to a form tap and ran the rest of the 125 piece order with no problem.
    Funny, when it happens to me, it's always at the last hole:cheers:

  4. #4
    Registered
    Join Date
    Jan 2007
    Posts
    1349

    Re: Well, I did it.

    This week I tapped about 800 blind 4-40 holes 0.25" deep in 6061-T6 using a Balax roll tap in a Procunier 1E tapper on my Tormach 1100. Spindle running at 1200 RPM, I feed the Procunier at 100%: down feed 30 IPM, no dwell, retract 60 IPM . Relton A9 was used as tapping fluid. No broken taps.

    Don

  5. #5
    Registered
    Join Date
    Mar 2009
    Posts
    1873
    Quote Originally Posted by Don Clement View Post
    This week I tapped about 800 blind 4-40 holes 0.25" deep in 6061-T6 using a Balax roll tap in a Procunier 1E tapper on my Tormach 1100. Spindle running at 1200 RPM, I feed the Procunier at 100%: down feed 30 IPM, no dwell, retract 60 IPM . Relton A9 was used as tapping fluid. No broken taps.

    Don


    I don’t have a Procunier tapping head, but since I learned to use the T/C tapping head I don’t think I need one.
    You can buy GOOD PARTS or you can buy CHEAP PARTS, but you can't buy GOOD CHEAP PARTS.

  6. #6
    Registered
    Join Date
    Jan 2007
    Posts
    1349

    Re: Well, I did it.

    Quote Originally Posted by Steve Seebold View Post
    I don’t have a Procunier tapping head, but since I learned to use the T/C tapping head I don’t think I need one.
    I owned a set of Tormach T/C tapping heads and found that compared to the Procunier head in tapping BLIND holes with the Tormach the T/C heads are way too slow. I sold that set of T/C heads. It would have taken way too long to tap the 800 BLIND 4-40 holes with a T/C head on a Tormach. I have tapped 10's of thousands of BLIND 4-40 holes in 6061-T6 with my Tormach and Procunier tapping head using Balax roll taps with excellent results. The form tap forges not cuts so I first start with a spot drill much deeper than I would with a cutting tap to accommodate the metal extruded at the hole top from the form tap.

    Don

    Don

  7. #7
    Registered
    Join Date
    Nov 2012
    Posts
    329

    Re: Well, I did it.

    By "roll taps" do mean the forming taps? (no chips)

    A fellow's gotta be BLIND to not see the benefit of that :-)

    Do you find that the threads are strong enough when forming in aluminum?

  8. #8
    Registered
    Join Date
    Jan 2007
    Posts
    1349

    Re: Well, I did it.

    Yep a by roll tap I mean forming tap. Thread Forming vs Cutting | Balax | Forming Taps, Cutting Taps, Thread Gages

    One still has the problem with either a form tap or cutting tap in tapping in the Tormach that doesn't have a servo controlled spindle of quickly tapping blind holes. The Tormach spindle cannot stop and reverse instantly so one has to go very slow when tapping blind holes. My solution is to use a Procunier reversing tapping head with the double cushioned cone clutch that stops tapping at a predetermined depth within 1/3 rev. Also I added the Pro-Quik quick change attachment so each tap size can be quickly changed in the Procunier and in fact each tap size is entered in the tool height table and given a separate tool number. https://www.createch-design.com/Down...ro-QuikTap.pdf
    I then measure each tap size in the Procunier offline on my surface plate and enter that height in the tool table. The Procunier reversing tapping head makes tapping blind holes really fast for me. E.g. tapping 4-40 blind holes I run the spindle at 1200rpm feed at 100%: downfeed 30IPM, no dwell, Retract 60IPM. Try tapping blind holes with the T/C tapping head in the Tormach at those rates.

    Don

    Measuring tool height of each tap size offline
    Attachment 417934


    Procunier in Tormach
    Attachment 417936


    Pro-Quik
    Attachment 417938

Tags for this Thread

Posting Permissions

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