I found this file on an old thumb drive.
http://www.mig-welding.co.uk/forum/...1/?temp_hash=2f912a1bf9bc185d79bd6147018fd7a8
Its a table showing recommended drilling speeds for hss drills in different materials.
You can print it out & have it in the workshop for reference.
Or you can use these simple formulas I worked out from the table. I have these typed in word but I can't attach them.
Imperial Drill Sizes
Mild Steel 240/dia”
Carbon Steel 200/dia”
Cast Iron 160/dia”
Stainless Steel 300 grade 80/dia”
Aluminium 800/dia”
Brass 600/dia”
Bronze 120/dia”
Wood/Plastic 1200/dia”
The way you use them is this. You divide the large number by your drill diameter in inches to give you your drilling speed in rpm.
EG for a 1/2" drill in mild steel is 240/0.5" = 480 rpm
Here's the table for metric drill sizes.
Mild Steel 6000/dia(mm)
Carbon Steel 5000/dia(mm)
Cast Iron 4000/dia(mm)
Stainless Steel 300 grade 2000/dia(mm)
Aluminium 20,000/dia(mm)
Brass 15,000/dia(mm)
Bronze 3000/dia(mm)
Wood/Plastic 30,000/dia(mm)
These tables are small enough to print, laminate & stick onto your drill or drill box.
http://www.mig-welding.co.uk/forum/...1/?temp_hash=2f912a1bf9bc185d79bd6147018fd7a8
Its a table showing recommended drilling speeds for hss drills in different materials.
You can print it out & have it in the workshop for reference.
Or you can use these simple formulas I worked out from the table. I have these typed in word but I can't attach them.
Imperial Drill Sizes
Mild Steel 240/dia”
Carbon Steel 200/dia”
Cast Iron 160/dia”
Stainless Steel 300 grade 80/dia”
Aluminium 800/dia”
Brass 600/dia”
Bronze 120/dia”
Wood/Plastic 1200/dia”
The way you use them is this. You divide the large number by your drill diameter in inches to give you your drilling speed in rpm.
EG for a 1/2" drill in mild steel is 240/0.5" = 480 rpm
Here's the table for metric drill sizes.
Mild Steel 6000/dia(mm)
Carbon Steel 5000/dia(mm)
Cast Iron 4000/dia(mm)
Stainless Steel 300 grade 2000/dia(mm)
Aluminium 20,000/dia(mm)
Brass 15,000/dia(mm)
Bronze 3000/dia(mm)
Wood/Plastic 30,000/dia(mm)
These tables are small enough to print, laminate & stick onto your drill or drill box.