Blind Hole With a tapping head

I have a simple question but I don't know the answer.
Can I use a tapping head to tap a blind hole ?
Mike Miller
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Yes, with two caveats. One, do your setup carefully . If the tap bottoms in the hole, chances are it will snap off. Two, use spiral fluted taps. These eject the chips up and out of the hole.
Paul K. Dickman
Mike wrote in message ...
Reply to
Paul K. Dickman
Yes you can, but you are wise to select a tap that is suited to the chore. Spiral fluted taps lift chips, gun type taps drive them in front of the tap. If you have enough room for the chip, and you don't care if the chip is difficult to remove, or you intend for it to remain in the hole, gun taps work fine for blind holes, too, as long as there's a place for the chip to accumulate. Be certain to lubricate your taps well, choosing a lubricant formulated expressly for tapping. It's the key to success.
Don't trust to stopping where you think you want to be. Be sure you set a spindle stop so you don't over drive the tap depth. It's pretty much ALWAYS a good idea to NOT drive 4 flute hand taps with a tapping head. Unless you back the tap off roughly every quarter turn, the chip load will generally break the tap, so that rules out using them in a tapping head. Extra fine taps are somewhat more forgiving than coarse ones, but none of them tap well under power.
Reply to
Harold & Susan Vordos
My Tapmatic 50X's have an adjustable clutch, so that if you do happen to tap too close to the bottom of the hole... the clutch will slip rather than breaking the tap. It's not meant as a substitute for the proper set-up and it's not made to be bottomed out on a regular basis (according to the warning label)... but it's a "safety" feature that helps prevent broken taps. That's about all I (think I) know about it... except that it seems to work well. My smaller "A" and "A1" Tapmatics don't have the clutch... but the larger "R7" does; so I guess you would have to check the specs before you bought one. David
Reply to
David Courtney
Depends upon the tapping head you have. If it has a forward torque clutch, you will have no problems with hitting the bottom of the hole and damaging the tap. My first experience with tapping heads was putting inserts into plastic panels. Unfortunately, the holes were odd shaped and not all the same size so one hole would often stop short of seating while another hole needed to be watched so that the inserter would start backing out when the insert was just seated or it would just spin in the plastic, destroying the panel.
-- Bob May Losing weight is easy! If you ever want to lose weight, eat and drink less. Works evevery time it is tried!
Reply to
Bob May
You are also wise (beyond your years) if you drill the blind hole a hell of a lot deeper then the required thread depth, if you can do it.
Reply to
Ralph Kennedy
Yep. I will try my darndest to use a good two-flute gun tap when using the Procunier tapping head. I've done blind holes with it as well. Typically the first one is done *real* careful without the stop, to see where the chip depth at the bottom will bind up the tap.
Then I set the stop to be well away from that zone.
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Reply to
jim rozen
Yes, absolutely. What material? If possible use a form tap and you won't have to worry about the chips, other than left by drilling. But those chips should not be there.
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Being a rookie myself, I checked it out on the web pages.
Mine is depth controlled.
the other trick is to use taps - special for blind that pull chips up.
Otherwise - you will have to clean clean clean.
Reply to
Martin H. Eastburn

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