Monitor Steam Engine

[sco]

That Enco one looks good Zee but have you checked your taps for the size of square - I have a feeling you will find that one will only do the larger end of the range and not the smaller tap sizes we frequently use.

I like the Starrett tap wrenches - I mostly use their 93A and 93B,

Simon.

[zeeprogrammer]

Thanks Simon.

Yes. I have one for smaller taps. It has a sliding rod in the end that I can hold either by a chuck in the tailstock or a 1/4" collet in the mill.
Good for taps with square shanks that go up to 1/4".
I needed one for this 1/2"-40 tap that has a 0.275" square shank.

Thanks for the help everyone.

[mklotz]

INMNSHO, a T-tap wrench without an integral guide pin is worthless.  I think the one from ENCO is such but it doesn't look like my piloted one so I can't be sure.  Many are center-drilled at the top of the shank to take a guide center but as soon as the tap bites, the tool will draw away from the center.  They're a PIA to use.  Get the type with a free-turning sliding pin as the guide.

Remember, the guide pin isn't just to initially align the tap.  It serves  to resist side pressure as the tap descends into the work.  It's the inadvertent side pressure that breaks taps.

Of course, you could make an insert that would hold a tap for your die holder.

[Don1966]

INMNSHO, a T-tap wrench without an integral guide pin is worthless.
Of course, you could make an insert that would hold a tap for your die holder.

Yep, make it like this one. Just make sure to make the front hole large enough to except a collar that holds the tap. And make different size collars for the different tap shank sizes.

[zeeprogrammer]

Many are center-drilled at the top of the shank to take a guide center but as soon as the tap bites, the tool will draw away from the center.  They're a PIA to use.  Get the type with a free-turning sliding pin as the guide.
Remember, the guide pin isn't just to initially align the tap.  It serves  to resist side pressure as the tap descends into the work.  It's the inadvertent side pressure that breaks taps.
Of course, you could make an insert that would hold a tap for your die holder.

Thanks Marv. Yes, the center-drill at the top of that one holder bothered me for that reason. I think (not sure) that the other I chose has some slide to it, not as much as my other holder (or Don's) but easier to adjust the tailstock as the tap goes in. The side pressure issue is why I want the tailstock (or mill collet) to hold the other end. In the 'early' days I've done it by hand...with either disastrous or unsatisfactory results.

Don...how is it (i.e. I'm guessing the collar) holding the tap's shank? And how is the collar held?

Is there a tommy bar hole?

I see the idea of a collar (or Marv's insert) that could be used in the die holder. Neat idea.
That just leaves understanding how the die is held in the collar.

Make a square hole?

  yeah right  me
I'm good at ovals.

[Jasonb]

The only thing I would watch with the larger size T type is their length, by the time you have  a large (long) tap in it you may start to run out of Z height on the mill.

I hardly ever use my Tee type prefering a bar type.

[mklotz]

I see the idea of a collar (or Marv's insert) that could be used in the die holder. Neat idea.
That just leaves understanding how the die is held in the collar.

Make a square hole?

I presume you meant to say how the tap is held in the collar.  With a square hole you only need something to keep it from falling out - setscrew or toothpick wedge.  The hole walls will take the torque thrust.

My homemade tap wrenches ...

http://www.homemadetools.net/forum/tap-holders-26298

use a hole to match the tap diameter to align the tap and a setscrew bearing on the tap square to resist the torque.

Jason's point is well taken.  That's why I made the large wrench shown on the right in the URL mentioned above.

[zeeprogrammer]

Thanks Jason. Good point.

Thanks Marv. Set screw. And thanks for the link to your taps. I remember them.

My notebook mostly has tables and notes. It's time to print images and store them as well.

[crueby]

I see the idea of a collar (or Marv's insert) that could be used in the die holder. Neat idea.
That just leaves understanding how the die is held in the collar.

Make a square hole?

I presume you meant to say how the tap is held in the collar.  With a square hole you only need something to keep it from falling out - setscrew or toothpick wedge.  The hole walls will take the torque thrust.

My homemade tap wrenches ...

http://www.homemadetools.net/forum/tap-holders-26298

use a hole to match the tap diameter to align the tap and a setscrew bearing on the tap square to resist the torque.

Jason's point is well taken.  That's why I made the large wrench shown on the right in the URL mentioned above.

Marv - those tap holders look great - been looking to find something like that, was not sure how to design one - gonna have to make up a set! Is there something (grub screw in channel?) that keeps the free spinning post on the top end from coming out?

Thanks!

[sshire]

Zee
I see guys hand guiding taps and cannot imagine doing that. Guessing that decades of practice might work. For me, the T-handle with extended guide rod to insert into a chuck or collet is the only way I've ever tapped on the lathe or mill. That way, I know it's going straight into the hole. I do find that spiral point (for through holes) and spiral flute (for blind holes) taps make the job easier and less of a butt-clenching experience. For anything 2-56 and smaller, I use form taps (Balax are my favorites) which do not create any chips. Tapping fluid (not coolant) is essential.

[crueby]

Zee
I see guys hand guiding taps and cannot imagine doing that. Guessing that decades of practice might work. For me, the T-handle with extended guide rod to insert into a chuck or collet is the only way I've ever tapped on the lathe or mill. That way, I know it's going straight into the hole. I do find that spiral point (for through holes) and spiral flute (for blind holes) taps make the job easier and less of a butt-clenching experience. For anything 2-56 and smaller, I use form taps (Balax are my favorites) which do not create any chips. Tapping fluid (not coolant) is essential.

Hi Stan,  I've seen spiral flute taps but never tried them, thought they were for powered use or something. What is their advantage? Always used straight flute ones, what have I been missing?

[mklotz]

Marv - those tap holders look great - been looking to find something like that, was not sure how to design one - gonna have to make up a set! Is there something (grub screw in channel?) that keeps the free spinning post on the top end from coming out?

Thanks!

No, they're not restrained.  That way, if tapping a very deep hole, the tap holder can come free of the guide rod.  You don't want the tap trying to screw into the hole while a restraint keeps it from doing so.   Not to say that a restraint of some sort would be wrong; just my way of doing it.  Treat everything I describe here as ideas awaiting your improvements.

As pointed out, the larger holder uses bushings to accommodate various size tap shanks.    If you do your own design, keep these as simple as possible so, in the heat of battle, when you need a special size, you need only run a drill through a chunk of standard-size rod to get back on track.

[mklotz]

Thanks Jason. Good point.

Thanks Marv. Set screw. And thanks for the link to your taps tap holders. I remember them.

My notebook mostly has tables and notes. It's time to print images and store them as well.

Paper is so passe.  Do what I do...

Make a bookmark folder for each forum you visit.  Bookmark good stuff and reword the bookmark title to something that will tickle your memory when you read it.   

[zeeprogrammer]

Thanks Jason. Good point.

Thanks Marv. Set screw. And thanks for the link to your taps tap holders. I remember them.

My notebook mostly has tables and notes. It's time to print images and store them as well.

Paper is so passe.  Do what I do...

Make a bookmark folder for each forum you visit.  Bookmark good stuff and reword the bookmark title to something that will tickle your memory when you read it.

Computers are so untrustworthy.

I remain passe.

(Yeah I know. Computers are actually unforgiving. They do exactly what they're told to do.)

I'm still a touchy-feelie guy.
Some know this. Others need to find out. 

[Hugh Currin]

Reading this I just came up with an idea. How about taking a tap wrench like this one (from MSC) or similar.

Then pull the handle out and press fit it into a sliding sleeve, like a tail stock die holder, similar to this (from Little Machine Shop).

The trick being to start with a tap wrench giving the ability to hold a range of taps. I should try that, if I can only come up with the time.


Or, one could use a spring center in the tail stock with a stock tap wrench as above. Here I'm using a spring center for tapping in the mill.

You can only see the bottom tip of it here. I'd be using this in the lathe but the spring center I have is too large to fit into my tail stock chuck (3/4" to fit a Tormach collet). I should build a smaller one of these too.

Wow, you can even buy these from Little Machine Shop in 1/2" shank, $13.50. I'll have to order one upon my next order.

Hope this is of interest, and maybe helpful.

Thanks.

Hugh