I need tap holding advice for the mill

[scattermaster]

Hello again,
Recently I needed to drill and tap a bunch of 1/16 NPT ports in some steel plates.
As hard as I tighten my drill chuck, the tap goes in a few turns and then slips in the chuck.
I tried using a collet and had the same result.
I got the job done but I know I'll be doing more of these and hoping I can come up with a better way to hold my taps.
?? suggestions?
Oh, and my drill bits slip too. My chuck is 1/2" and is the one I bought from Precision Mathews when I bought the mill.
Jim

 

[OTmachine]

Spring center and tap wrench. Or dedicated tapping head. My .02

 

[scattermaster]

what does spring center and tap wrench mean?
I tried doing a few of them by starting on the mill and then finish up manually with a tap holder but the threads look ugly and I'm afraid those ones will leak...

 

[mmcmdl]

Use a skip tooth tap for less pressure needed ? What kind of mill are you using ?

 

[Eddyde]

It sounds like the chuck isn't tight enough? Try tightening the chuck using the key in all three holes, it makes a difference.

 

[OTmachine]

Like these:

 

[OTmachine]

And possibly a taper reamer if precision is needed.

 

[woodchucker]

what does spring center and tap wrench mean?
I tried doing a few of them by starting on the mill and then finish up manually with a tap holder but the threads look ugly and I'm afraid those ones will leak...

npt is a tapered thread, so it needs to be done manually toward the end. I wasn't even aware of 1/16 npt... I thought 1/8 npt was the smallest.
I'll assume you are new to tapping.. because I don't know.
You need to use cutting oil. Tap magic or other .
you can start with the mill it will keep the tap straight. use plenty of oil.
once it stops, you should back the tap out, and clean the chips out of the tap and hole (do this since it's tapered and getting tighter as you go).
try again with the mill. if it doesn't go, time to go by hand.. Tap wrench or tap holder has two handles to help you keep it aligned.
keep using plenty of oil, and back it off and clean the chip out/off.

Frequent backing off will help...

 

[mmcmdl]

The 2 in the top middle will drive that tap .

 

[mmcmdl]

https://www.mscdirect.com/basicsof/pipe-taps

Couple items down are skip tooth/interupted thread taps . Well worth the $$$$ if doing multiple holes .