Well, well, well. That is a mighty ambitious project and I can not even imagine what that drill bit is made of.
“Well, well, well. That is a mighty ambitious project and I can not even imagine what that drill bit is made of.”
Having done a lot of drilling, they will pull up the drill steel and change the head as needed. That is why it takes so long...
They have to put it down and drill for awhile and then pull it all back out then repeat over and over until they get to the targeted depth. It is monotonous...
Steel with diamond chips, replaced often.