Best tap for different materials

[lensman57]

Hi to All,

I just wanted to start this topic as the one for the "tapping cast iron" is somewhat off the topic now. I would personally be very interested in any expereince that other members have with different types of taps for different materials. Recently I have been using a combination of Red and Yellow ring taps with great success for Aluminium and steel even though I think they are meant as machine taps as against hand tapping that I preffer.
Below is a link to my supplier.

http://www.ebay.co.uk/itm/200710862152?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

Regards

A.G

 

[mgbrv8]

I love spiral taps. Even in deep copper stuff it works great.

Dave

 

[rake60]

Spiral flute taps are great for soft material and blind holes in steel because they expel the
chip as a drill bit would.

Spiral Point taps (sometimes called gun taps), like the one on the right, are excellent for through holes.
They displace the chip at a angle into the flutes of the tap so there is less manual breaking of that chip
required.

Both designs were intended for machine and CNC application but I use them as hand taps all the time.

Rick

 

[Blogwitch]

Rick,

Both designs were intended for machine and CNC application but I use them as hand taps all the time.

As you have said, really for machine use.

My personal view is that for normal workshop use, there is no need to go for these special forming taps, unless you have a specific job that requires them, say thin stainless sheet, where you would use a fluteless thread forming tap, or a spiral tap that throws the cuttings backwards out of the hole, used when helicoiling spark plug holes, with the head still in place, and even then, the tap would be covered in grease to catch any stray swarf, to stop it going down into the hole.
They are nice if they come as freebies, as ALL mine have done, but otherwise, I have found that I have never had to buy or use anything other than the standard straight taps in the home shop.

More important than anything else is the right sized tapping hole for the thread size and type, plus the material being used, and if required, a very good quality, high pressure cutting lubricant.


John