I called my sandvik rep and got this: Anything over 8Xd definitely need pilot. 5xd you may want to spot with something with a spot drill with an angle equal to or greater than the drill being used. Also, when drilling radially a small spot may prevent drill walking. When you start drilling deeeeeeeep holes 12XD -18XD and up you should always call and make a plan of attack with your local tool rep.
Yes you can say the surface finish of the chip indicates you have the correct data for a successful operation but the shape of the chip is the most important factor when determining excellent chip control. Other factors can contribute to a shiny finish of the chip such as material hardness, coolant type and concentration with a dull chip showing not enough heat in the process so the solution would be to increase the speed. Best regards Robert Smith Global Application Specialist
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I respect how still you stand while speaking... like a damn chuck head...only your mouth moved.
Priceless. Ty.
What I'm missing is information about spot drilling in combination with solid carbide drills (when to use or not and choice of angles).
I called my sandvik rep and got this: Anything over 8Xd definitely need pilot. 5xd you may want to spot with something with a spot drill with an angle equal to or greater than the drill being used. Also, when drilling radially a small spot may prevent drill walking. When you start drilling deeeeeeeep holes 12XD -18XD and up you should always call and make a plan of attack with your local tool rep.
Hi,
Thank you for this input. We will add this to the list of subjects for future tips films.
♡
Hello Sandvik, I heard that the surface finish of the chip also says a lot. Shiny means a good cutting speed, dull is too slow. Do you agree?
Yes you can say the surface finish of the chip indicates you have the correct data for a successful operation but the shape of the chip is the most important factor when determining excellent chip control. Other factors can contribute to a shiny finish of the chip such as material hardness, coolant type and concentration with a dull chip showing not enough heat in the process so the solution would be to increase the speed.
Best regards
Robert Smith
Global Application Specialist
Good stuff.
El arte del mecanizado
Chip Jammin’ 🇯🇲
🍻