Update for the 3.4mm hole goes 204mm deep

[CNC-ERIC]

HI, there,

 

I bought a chip-clearing drill bit (1/8" x8.7", did not find 3.4mm long drill, told to the customer) from Mcmaster.

 

results are good. only thing made me headache was handling with the drill bit whirling by reducing rpm manually, restore the rpm when close to the predrilled depth.

 

first drill to 1.4" deep,

second drill to 3.0" deep

third drill witht the long drill, rpm825 feed 2.3ipm peck0.25"

 

at the mouth, dia is about 0.002" bigger than 0.125", could not check the straightness.

 

thanks for your input.

 

Eric