Tap sizes

[Richard Hed]

Forgot something.
I use spiral flute taps about 98% of the time and have never broke a tap. In my honest the only reason a tap breaks is so to operator error.

Does the spiral in very small sizes hold up? Are there even spirals in the 8-32 and smaller range?

 

[Richard Hed]

I just chekt out this page:
https://www.victornet.com/tools/Spiral-Flute-Taps/201.htmlI'll chek other prices on other pages and report back

 

[Badhippie]

Richard
yes you can get them down to #0-80 bottom and starter taps and class 2B and I think even 3B or 3BX

 

[Badhippie]

Richard
Personally I don’t use them under 1/4 inch just because. I have some kind of a trust issue the shank gets pretty small below a 1/4 inch. Just my own opinion

 

[Jasonb]

M2 is the smallest I have and find them fine to use.

This is M3 under power in 6082


And M6 in steel


They work just as well by hand and you don't have to keep winding the tap backwards to break the chip, just leave the spirals of swarf to clear themselves. this is how a spiral point pushes it out the bottom of a through hole

And as shown on the videos the spiral flute ones eject it out the top so are best for blind holes

 

[methuselah1]

Spiral flutes are great for most materials, but experience has shown that they tend not to like the stainless steels too much.

-Andrew UK

 

[Richard Hed]

Spiral flutes are great for most materials, but experience has shown that they tend not to like the stainless steels too much.

-Andrew UK

I would expect that. Stainless doesn't like anything. Even so, I'm going to start stocking up on them to test them first, then stockpile if I am satisfied.

 

[Jasonb]

If you really have a lot of stainless to do then you can start to go down the route of material specific taps which have slightly tweaked geometry and coatings to best suit cutting a particular material. Not really practical for hobby use, I just buy general purpose ones.

Ones for stainless are usually denoted by a blue ring

https://www.cutwel.co.uk/threading/...ainless-steel-inox-metric-coarse-machine-taps

 

[Badhippie]

Richard
I use the standard spiral non coated in stainless without much problem 80% of my drilling is in stainless. Depending on the stainless 316 no problem. Harder stainless then I will use coated ones. But for general purposes good quality non coated for home should work just fine. Will probably cover 95% or more of the material you tap. And of corse coated ones will last longer this you already know. And tap magic will be good enough to help keep them sharp. I doubt you will be using them enough for flood coolant. I tap most all my holes on the mill with a tapmatic head or with a tap holder. To me they seem to produce better threads then standard taps especially when tapping at 75% thread engagement and even seem better then most taps at 50% thread engagement.
Hope this all helps try them I think you will like them
Thanks
Tom

 

[Richard Hed]

Richard
I use the standard spiral non coated in stainless without much problem 80% of my drilling is in stainless. Depending on the stainless 316 no problem. Harder stainless then I will use coated ones. But for general purposes good quality non coated for home should work just fine. Will probably cover 95% or more of the material you tap. And of corse coated ones will last longer this you already know. And tap magic will be good enough to help keep them sharp. I doubt you will be using them enough for flood coolant. I tap most all my holes on the mill with a tapmatic head or with a tap holder. To me they seem to produce better threads then standard taps especially when tapping at 75% thread engagement and even seem better then most taps at 50% thread engagement.
Hope this all helps try them I think you will like them
Thanks
Tom

I won't be doing much SS anyway.

 

[Badhippie]

There are days when I wished I didn’t do much stainless either. But that only seems to happen when I am home.
Tom

 

[Richard Hed]

There are days when I wished I didn’t do much stainless either. But that only seems to happen when I am home.
Tom

I have a couple small projects with SS, but mostly any SS I would use I would be tig welding and maybe bore a few holes but very little tappng

 

[awake]

The smallest spiral flute or spiral tip that I have used is an M3, closely followed by a 6-32. I've not used the M3 as much, but never broken it, despite the fact that the spiral flute seems to leave very little metal in the tap. I have occasionally broken a 6-32 spiral tip tap. With the 1/4-20 or larger taps, you can be pretty aggressive with a spiral tip tap ... with 6-32, 8-32, and 10-24, you have to be more patient and sensitive. Oddly, the worst of these for me is the 10-24 - it seems big enough to be more aggressive, but the size of thread weakens it enough that it really won't stand too much. By contrast, I find 10-32 to be very forgiving.

 

[roncohudd]

Explains why the term “plug tap” confuses me in these forums since it seems to be used for different things. I guess we should all go to spirals to avoid confusion. I will have to buy one to try.

 

[awake]

The smallest spiral flute or spiral tip that I have used is an M3, closely followed by a 6-32. I've not used the M3 as much, but never broken it, despite the fact that the spiral flute seems to leave very little metal in the tap. I have occasionally broken a 6-32 spiral tip tap. With the 1/4-20 or larger taps, you can be pretty aggressive with a spiral tip tap ... with 6-32, 8-32, and 10-24, you have to be more patient and sensitive. Oddly, the worst of these for me is the 10-24 - it seems big enough to be more aggressive, but the size of thread weakens it enough that it really won't stand too much. By contrast, I find 10-32 to be very forgiving.

Hah - I should have known better than to offer any suggestion that 1/4-20 spiral tip could stand some aggressiveness. I broke one last night. I think it was getting dull, which I suspect is the typical reason for breaking a tap of this size. After I carbide-milled the remains of the tap out, I tried again with a different 1/4-20 spiral tip tap, and it went smoothly, no problems at all.

 

[Badhippie]

Awake
That’s the way it always happens to me. Open mouth wider and insert the other foot. Lol lol
Thanks Tom

 

[mrehmus]

The smallest spiral flute or spiral tip that I have used is an M3, closely followed by a 6-32. I've not used the M3 as much, but never broken it, despite the fact that the spiral flute seems to leave very little metal in the tap. I have occasionally broken a 6-32 spiral tip tap. With the 1/4-20 or larger taps, you can be pretty aggressive with a spiral tip tap ... with 6-32, 8-32, and 10-24, you have to be more patient and sensitive. Oddly, the worst of these for me is the 10-24 - it seems big enough to be more aggressive, but the size of thread weakens it enough that it really won't stand too much. By contrast, I find 10-32 to be very forgiving.

Back in 1997, I tapped 1500 holes in 1/4" X 1" 306 Stainless rod with one spiral tap. Did it all under power on my Bridgeport at the slowest speed. Nice to be able to reverse under power. These were 'nuts' to be put in aluminum tubing to make animal tracking antennas. These taps (bought 2, used 1) have a black coating and came from Germany. Stil have them and use them.