provide explanation or sources Calculate appropriate cutting

provide explanation or sources

Calculate appropriate cutting speed (in FPM) for drilling 1212 steel with a 1/4\" diameter high speed steel drill at a feed rate of 0.015\"/rev. V = Cutting speed (fpm) Vo = Cutting speed from tables Ff = Feed Factor (see tables) Fd = Diameter Factor (see tables)

Solution

Answer:

Cutting speed, in the US, is generally expressed in terms of Surface Feet Per Minute often expressed as (SFM) or (SFPM). SFM is the speed at which tool tip is cutting through the material. Imagine you are dragging a stick behind a car that is traveling at 60 miles per hour. In one minute your stick has traveled 5,280 feet across the ground. That would be expressed as 5,280 SFM.

Unless you are running a shaper or other linear cutting machine, your surface feet per minute is based upon the rotational speed of either the part or the cutting tool. Obviously, on a lathe it is the chuck speed that matters. On a milling machine it is the spindle speed that matters.

The other major factor in calculating SFM is the diameter of the diameter you are cutting on a lathe or the diameter of the tool you are using on the milling machine. So here are the steps to calculating SFM/FPM.

FPM (V)= SFM = RPM * Diameter
                                    K

Where K = Constant use for SFM calculations (3.8197)

               =1212 x 0.25/ 3.8197 =   79.325

Table is not in question hence the same cannot be solved by given formula.