The ideal weight or force to push a drill

[abdulbadii]

TL;DR Summary

The ideal weight or force to push (bit ibeing n) a driller down when drilling (stainless) steel

What is and how is the estimation of the ideal weight or force to push (bit being in) a driller down when drilling (stainless) steel to bore 3-9 mm hole?

 

[jrmichler]

It's not a matter of force. Drilling metals, especially metals with large work hardening tendencies such as stainless steel, is best done with a constant feed rate. Too large a feed per revolution will break the drill bit. Too low a feed per revolution will cause the work hardened stainless to destroy the drill bit. And this is a photo of a 1/2" drill bit that I destroyed a few days ago doing exactly that. It was A286 stainless, which is harder to machine than the more common 300 series stainless steels.

Part of the problem is that the slowest speed on my drill press is 490 RPM, which is over twice too fast for drilling this alloy with a high speed steel drill bit.

The force is also dependent on the drill bit geometry. For example, split pointed bits need less force.

 

[Baluncore]

What is and how is the estimation of the ideal weight or force to push (bit being in) a driller down when drilling (stainless) steel to bore 3-9 mm hole?

If you cannot set the feed rate, the bit-force should be held steady, so the drill keeps cutting.
Flood the hole with coolant / lubricant.

With practice, you should be able to produce two continuous helical coils of cut material, that pass freely up and along the flutes of the drill.

The relief angle on the drill will decide the maximum feed rate. Learn to grind drill bits to suit the material you are cutting.

https://en.wikipedia.org/wiki/High-speed_steel#Types
For stainless steel, use a cobalt HSS drill bit, M35 or M42.
https://en.wikipedia.org/wiki/High-speed_steel#Cobalt_High_Speed_Steels_(HSS)