1, how can I make the tapped threaded hole perpendicular to the end face?

I don't know whether you attack with a machine or with your hands. The key point of machine attack is to ensure the parallelism of machine tool worktable (of course, pay attention to fixture). As for hand attack, it depends on the technical level of skilled workers.

2 How to make the tapped threaded hole smooth?

Another friend said that "different processing environments and conditions require different processes", which is more general. Personally, to ensure the smoothness of threaded holes, we must pay attention to several aspects:

(1) When selecting the bottom hole of the thread, if the bottom hole is too large, the tapping will be smoother, but it is difficult to ensure the thread accuracy, and if the bottom hole is too small, it is difficult to tap and remove chips, which will affect the smoothness of the thread hole.

⑵ Selection of cutting fluid Reasonable selection of cutting fluid can not only improve tapping efficiency, reduce tap wear, but also improve the smoothness of threaded holes.

(3) The rotating speed of the tapping machine is generally the recommended rotating speed of the tapping machine (of course, some special materials need to be adjusted).

(4) The choice of faucet, don't choose some garbage factory production, it is best to choose some brands, and you can choose imported ones if you have the conditions. I am by no means worshipping foreign things and obsessing foreign things here. My previous unit had to process some fine threads on the aluminum plate, which were made in the United States, but it was not good to change several domestic brands. A tap can't process several products before it breaks (thread is relatively small, thread depth is large, chip removal is difficult, and it is easy to break). Later, this problem was solved through the faucet (import) provided by the customer.

5] One more thing, what is the material you need to process? If it is non-ferrous metal, especially copper, there is nothing the fairy can do, hehe.

Humble opinion, laugh!