Tapping Tidbits

Tapping Tidbits: Limit for Form Taps + Peck Tapping + Thread Mill When Risk is High

While many machinists may think form taps are only for aluminum, the answer to the quick question is you can form tap materials up until they have a hardness greater than 36 HRC, which is about 340 BHN. That actually covers a surprisingly wide range of materials including a lot of steels. That information comes from tapmaker Titext via the link I’ve provided.

Second tapping tidbit: you can “peck” tap difficult holes. For the most part, you will need rigid tapping to be able to peck tap because the tap has to get itself synchronized back to the same set of threads as it goes in and out of the hole. Peck tapping is only called for with a cutting tap–no benefit to pecking with a form tap. Peck tapping is also an excellent way of clearing the long stringy chips often found when machining plastics and some other materials .

Last tapping tidbit: For the hardest materials, and especially when the cost of a broken tap is very very high, consider thread milling. You’re much less likely to break a thread mill, and if you do, it won’t be stuck in the hole the way a tap would be.

Article Resource cnccookbook.com