Question

when drilling metal
select one:
a. maintain enough pressure to keep the bit cutting but not enough to overload the bit
b. the general rule for spindle speed is: the larger the bit the slower the rpm
c. apply a cutting lubricant to the bit and allow it run down to the point of contact
d. all of these

Explanation:

When drilling metal, maintaining proper pressure ensures efficient cutting without damaging the bit. A general rule for spindle speed is that larger bits require slower RPMs to prevent over - heating and breakage. Applying a cutting lubricant helps in reducing friction, heat generation and prolonging the life of the bit and improving the quality of the cut. All these practices are important.

Answer:

D. All of these