Tapping using a Taig chuck?

I’ve noticed a BIG difference depending on the tap. I recently bought a new “American made” set of Ø5/16-18 4-flute. After fighting with my 3-jaw, I pulled my old tap out and noticed it was a 3 flute. Even being old, it cut 10 times better than the 4 flute set. Now I use 2 flute.

Tommy, I do it on my Mid America 4 jaw. You do have to cinch down on it and sometimes it will slip. What size drill bit are you using? Some people try to cheat with a 1/4 bit but it is much easier with the correct 17/64 bit. Having reverse helps too so you can work it in, back it out and go again.
Good luck with it!

Spiral flute tap might help.
http://www.amazon.com/16-18-Spiral-Flute-Taps-Helix/dp/B005RG96UM

I do it on my Mid America 4 jaw chuck all the time. If you take your time and back out frequently to clear the chips I have no problems at all.

wrap a piece of sand paper around the ferrule..... sand side in

don't think you are just going to ram the tap in..... work it back and forth

start with a starter tap and then switch to a bottom tap


Kim

Sharp taps are essential.
Funny enough, A lot of filled ferrule materials are actually very abrasive to cutting tools.
Coated TiN (gold) or TiAl (brownish colour) hss taps work well in these types of materials.

NC spiral fluted taps are designed for tapping into blind holes, Most knock the point off the front though.

Using brown paper between the jaws and work piece increases the friction to help hold materials that are otherwise difficult to hold, like teflon .

Neil

First advice, make bigger tommy bars to close the chuck tighter. More length equals more torgue when tightening. I use a 1/4" bottom cutting endmill to drill the hole and then a 3 flute tap. I use a normal tap then switch to a bottoming tap to finish it. Some materials 'grab' the tap more so, like PVC, JUMA, Isoplast to name a few. They tend to be more stringy than LBM and thermoset types which have very small chips, which make more of dust like chips. I chuck up a dowel in the rear chuck that has a rubber pad glued to the end of it and it pushes against the ferrule and gives some resistance to spinning. On the LBM styles, I only go partway in, back off a turn or so, then use an airhose with a football/basketball filler adaptor and a thin plastic tube attached and insert it between the flutes and give it a good blowout. It sends the chips out the other 2 flutes and allows me to continue without backing the tap all the way out. The others, I have to backout all the way multiple times to clear the hole and clean the tap.

Dave

Tommy-D said:

In a thread about something else,I think Joey made reference to potential problems in using a standard Taig soft-jaw chuck to tap threads in a ferrule.

I've only done that once,and ran into a problem,specifically I wasn't able to get the chuck tight enough to tap the ferrule effectively.

I managed to get it done,but had to work around it.

Anyone care to elaborate? Tommy D.

Click to expand...

Tommy,

Not trying to be a killjoy but why not just buy your ferrules pre threaded. They are very cheap. If your chuck does not hold the ferrule tight enough to do a ferrule and you need to thread an ivory ferrule or something not sold pre threaded I would do the one of the following.

(1) Use a through hole ferrule

(2) Center drill, step drill to .312 or whatever and bore the hole about .009 oversize. Then mount the ferrule in a vise between some rubber and tap it by hand with a tapered tap.

I have a mini lathe in my shop I use for a few small operations. You can pick one up pretty cheap. I even ordered a six jaw for mine from little machine shop as an upgrade. If your current chuck can't hold it, this is another inexpensive option.

Good luck,

Rick