Challenge Machinery
Steel: Uncoated steel drill bits will cover a majority of basic drilling applications - normal paper stock, light to medium weight.
CHT (Teflon): Teflon coated to prevent build-up and increase drill bit life by reducing heat. Works great for medium to heavy weight and coated stocks.
Marvel (Titanium): Titanium coated for maximum durability. Best for hard materials (i.e., plastics, card stock).
Fluted: Flutes line the inside of the drill bit for breaking up paper chips and preventing clogs. Recommended for hard materials like chipboard or card stock. (Note: fluted bits are only available in 1/4", 5/16", 3/8" and 1/2" diameters)
Keep Drills Sharp: Sharpen drills every 4 to 8 hours of use - even more when drilling through hard or abrasive stock. Most breakages occur as a result of dull drills.
Keep Drills Clean: This is especially true when drilling perfect bound books and glue. If the inside of a drill is not cleaned, glue will harden and snap a drill bit upon next use. Use a small brush with solvent to clean the inside of the drill bit. Bits can also be lightly oiled to reduce rust or corrosion when not in use.
Keep Drills Lubricated: Some bits are coated (i.e., Teflon), which will provide lubrication. Consider using a lubricating stick to reduce heat and clogging.
Below is a table of suggested speeds to run your drill machine for optimal performance at each drill bit diameter.
| Drill Bit Diameter | Speed (RPM) |
| 1/8" | 3000 |
| 5/32" | 2800 |
| 3/16" | 2700 |
| 7/32" | 2600 |
| 1/4" | 2500 |
| 9/32" | 2200 |
| 5/16" | 2000 |
| 11/32" | 1900 |
| 3/8" | 1700 |
| 13/32" | 1600 |
| 7/16" | 1200 |
| 1/2" | 1000 |
