Carbide beginner!
Carbide beginner!
(OP)
Drilling holes 6-9X diameter of drill with 1/16 Carbide drill and drill keeps braking. Any tips for a beginner would be appreciated.
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RE: Carbide beginner!
An afterthought are these drill bits of China origin?
Chocolates,men,coffee: are somethings liked better rich!!
(noticed in a coffee shop)
RE: Carbide beginner!
Is there any pilot hole?
Blind or through hole? If through, output face specs, angle with axis?
Material?
cutting parameters?
Run out on the tool at machine spindle?
Tool holder type?
Coolant Type and concentration?
It is not easy to say exact reason without these informations (even with these it is still not easy)
Then we can talk about the possibilities.
RE: Carbide beginner!
RE: Carbide beginner!
There are maybe 7,000 grades of carbide depending on how you count and how you feel about brand names. Wood drill bits won't drill steel well.
To give you an idea of the range of applications, here are the traditional C grades from WW II.
C grades classification
C-1 to C-4 are general grades for cast iron, non-ferrous and non-metallic materials
C-1 Roughing
C-2 General Purpose
C-3 Finishing
C-4 Precision
Steel and steel alloys - these grades resist pitting and deformation
C-5 Roughing
C-6 General Purpose
C-7 Finishing
C-8 Precision
Wear Surface
C-9 No shock
C-10 Light shock
C-11 Heavy shock
Impact
C-12 Light
C-13 Medium
C-14 heavy
Miscellaneous
C-15 Light cut, hot flash weld removal
C-15A Heavy cut, hot flash weld removal
C-16 Rock bits
C-17 Cold header dies
C-18 Wear at elevated temperatures and/or resistance to chemical reactions
C-19 Radioactive shielding, counter balances and kinetic applications
Thomas J. Walz
Carbide Processors, Inc.
www.carbideprocessors.com
Good engineering starts with a Grainger Catalog.
RE: Carbide beginner!
Number 2 is inadequate fixturing that forces the drill to bend to find or follow the hole. Carbide drills don't bend; they fracture.
While you're running the numbers for number 1 above, also look at the feed rate per tooth, and calculate how long it should take you to reach the depth you want. Chances are you're running too little axial feed, babying the drill... and that just work hardens some metals and burns the drill.
Using the recommended feeds and speeds will produce cycle time numbers that will astonish you... and if the drill's geometry is right, when you try doing it that way, you'll also be astonished to see nice short chips flying out of the flutes instead of clingy birds nests getting tangled up and making a mess of things... and the drills will last longer.
Mike Halloran
Pembroke Pines, FL, USA