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equipment:metalshop:titanpillardrill:usinglargebits [2026/06/29 18:06] – [3. Apply Cutting Fluid / Lubricant. Thread-cutting oil (or WD40 for aluminium). Do not use water.] ralawrenceequipment:metalshop:titanpillardrill:usinglargebits [2026/06/29 18:08] (current) – [5. Clean the Pillar Drill.] ralawrence
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 Before you start drilling, squirt a few drops of proper dark sulphur-based thread-cutting oil directly into the centre punch mark. For aluminium only, you can use WD-40. Re-apply 2-3 drops every time you lift the bit to clear chips. Before you start drilling, squirt a few drops of proper dark sulphur-based thread-cutting oil directly into the centre punch mark. For aluminium only, you can use WD-40. Re-apply 2-3 drops every time you lift the bit to clear chips.
 Drilling metal generates enormous frictional heat (often over 400°C). Cutting fluid performs three jobs: it cools the bit to prevent it from losing its hardness (temper), it lubricates the cutting edges to reduce friction and torque, and it flushes chips away from the cutting zone. Water causes instant thermal shock and rust; it boils off and does not lubricate, leading to rapid bit destruction. Drilling metal generates enormous frictional heat (often over 400°C). Cutting fluid performs three jobs: it cools the bit to prevent it from losing its hardness (temper), it lubricates the cutting edges to reduce friction and torque, and it flushes chips away from the cutting zone. Water causes instant thermal shock and rust; it boils off and does not lubricate, leading to rapid bit destruction.
-====== 4. Use a low speed. The bigger the bit, the slower the speed. ======+==== 4. Use a low speed. The bigger the bit, the slower the speed. ====
  
 Adjust the belt position on the pulleys to achieve the correct RPM. As a rough rule: for a 3mm bit in steel, use ~2000 RPM; for a 10mm bit, use ~600 RPM; for a 20mm bit, use ~250 RPM. When in doubt, choose the slowest speed. "Surface Speed" (the velocity of the cutting edge against the metal) must remain constant. A large bit has a massive circumference; if it spins fast, the outer cutting edges travel at hundreds of metres per second, generating so much friction that they glow red-hot and instantly go blunt. Slow speeds allow the bit to "slice" rather than "rub." Adjust the belt position on the pulleys to achieve the correct RPM. As a rough rule: for a 3mm bit in steel, use ~2000 RPM; for a 10mm bit, use ~600 RPM; for a 20mm bit, use ~250 RPM. When in doubt, choose the slowest speed. "Surface Speed" (the velocity of the cutting edge against the metal) must remain constant. A large bit has a massive circumference; if it spins fast, the outer cutting edges travel at hundreds of metres per second, generating so much friction that they glow red-hot and instantly go blunt. Slow speeds allow the bit to "slice" rather than "rub."
-====== 5. Always lower the drill slowly and let the drill bit do the work. ======+==== 5. Always lower the drill slowly and let the drill bit do the work. ====
  
 Use the feed lever to bring the rotating bit down until it just touches the metal. Then, apply gentle, steady downward pressure. Let the bit "bite" at its own pace; do not force or heave on the lever. You should see two even, curly chips forming. Forcing the drill down faster than it can cut causes the flutes (the spiral grooves) to clog with metal. When they clog, the bit stops cutting and starts rubbing, generating destructive heat. Letting the bit "cut" at its natural feed rate produces beautiful, continuous chips and maximises the bit's lifespan. Use the feed lever to bring the rotating bit down until it just touches the metal. Then, apply gentle, steady downward pressure. Let the bit "bite" at its own pace; do not force or heave on the lever. You should see two even, curly chips forming. Forcing the drill down faster than it can cut causes the flutes (the spiral grooves) to clog with metal. When they clog, the bit stops cutting and starts rubbing, generating destructive heat. Letting the bit "cut" at its natural feed rate produces beautiful, continuous chips and maximises the bit's lifespan.
-====== 6. Start by pecking the metal. Drill down about 5mm and then extract the bit. ======+==== 6. Start by pecking the metal. Drill down about 5mm and then extract the bit. ====
  
 Drill into the metal for about 5mm (roughly ¼ inch). Without switching the drill off, pull the feed lever back up to completely withdraw the bit from the hole. Bring it back down and drill another 5mm deeper. Repeat. This "pecking" action breaks the long, continuous spiral of swarf (chips). Long stringy chips wrap around the bit like a spring, which can violently whip around and cut your hands, or clog the flutes entirely. By extracting, you physically break those strings into manageable pieces. Drill into the metal for about 5mm (roughly ¼ inch). Without switching the drill off, pull the feed lever back up to completely withdraw the bit from the hole. Bring it back down and drill another 5mm deeper. Repeat. This "pecking" action breaks the long, continuous spiral of swarf (chips). Long stringy chips wrap around the bit like a spring, which can violently whip around and cut your hands, or clog the flutes entirely. By extracting, you physically break those strings into manageable pieces.
-====== 7. Clean away chips with a brush. Never use your fingers. ======+==== 7. Clean away chips with a brush. Never use your fingers. ====
  
 While the bit is lifted and the machine is running, use a stiff-bristled chip brush to sweep the hot, sharp swarf away from the hole and off the table into a scrap bin. While the bit is lifted and the machine is running, use a stiff-bristled chip brush to sweep the hot, sharp swarf away from the hole and off the table into a scrap bin.
 Freshly cut metal chips are extremely sharp (like razor blades), often have microscopic burrs, and are hot enough to instantly burn your skin. Brushing keeps your hands safely away from the rotating spindle. Using your fingers almost guarantees deep lacerations or tiny metal splinters that infect easily. Freshly cut metal chips are extremely sharp (like razor blades), often have microscopic burrs, and are hot enough to instantly burn your skin. Brushing keeps your hands safely away from the rotating spindle. Using your fingers almost guarantees deep lacerations or tiny metal splinters that infect easily.
-====== 8. Frequently lift the drill bit back up to allow chips to be cleared and add lubricant. ======+==== 8. Frequently lift the drill bit back up to allow chips to be cleared and add lubricant. ====
  
 At least every 10mm of depth, or whenever you hear the motor labouring, pull the feed lever up to full extension to completely clear the flutes of swarf, then apply fresh cutting fluid to the hole. At least every 10mm of depth, or whenever you hear the motor labouring, pull the feed lever up to full extension to completely clear the flutes of swarf, then apply fresh cutting fluid to the hole.
 Chips must travel up the spiral flutes to escape the hole. If the flutes become packed, the chips have nowhere to go; they get crushed at the bottom of the hole, causing extreme friction. Frequent lifting prevents the bit from seizing inside the hole, which would snap the bit flush with the metal (a nightmare to extract). Chips must travel up the spiral flutes to escape the hole. If the flutes become packed, the chips have nowhere to go; they get crushed at the bottom of the hole, causing extreme friction. Frequent lifting prevents the bit from seizing inside the hole, which would snap the bit flush with the metal (a nightmare to extract).
-====== 9. If drilling all the way through, go very slowly when breaking through. ======+==== 9. If drilling all the way through, go very slowly when breaking through. ====
  
 When the tip of the bit is just starting to poke through the underside of the metal, ease off the downward pressure to a mere feather-touch. Let the bit gently nibble its way through the final 1mm of material. As the bit exits the bottom, the cutting edges are no longer surrounded by metal on all sides. If you maintain heavy pressure, the bit will "grab" the remaining thin ring of metal, screw itself violently into the workpiece, and either snap the bit, shatter the workpiece, or violently yank it upwards off the table. Slow pressure ensures a clean, burr-free exit. When the tip of the bit is just starting to poke through the underside of the metal, ease off the downward pressure to a mere feather-touch. Let the bit gently nibble its way through the final 1mm of material. As the bit exits the bottom, the cutting edges are no longer surrounded by metal on all sides. If you maintain heavy pressure, the bit will "grab" the remaining thin ring of metal, screw itself violently into the workpiece, and either snap the bit, shatter the workpiece, or violently yank it upwards off the table. Slow pressure ensures a clean, burr-free exit.
  
 ________________________________________ ________________________________________
-====== Finishing ====== +===== Finishing ===== 
-====== 1. Turn off the drill and wait for it to stop spinning. ======+==== 1. Turn off the drill and wait for it to stop spinning. ====
  
 Hit the large red STOP button. Step back slightly and watch the chuck as it coasts down. Do not touch the workpiece, the chuck, or the bit until the rotation has completely ceased. Hit the large red STOP button. Step back slightly and watch the chuck as it coasts down. Do not touch the workpiece, the chuck, or the bit until the rotation has completely ceased.
 A heavy drill chuck has significant rotational inertia and can coast for several seconds. Touching a still-spinning bit with a rag or your hand can snag and pull you in. Furthermore, trying to "brake" the chuck by grabbing it damages the internal spindle bearings. Letting it stop naturally is the safest mechanical practice. A heavy drill chuck has significant rotational inertia and can coast for several seconds. Touching a still-spinning bit with a rag or your hand can snag and pull you in. Furthermore, trying to "brake" the chuck by grabbing it damages the internal spindle bearings. Letting it stop naturally is the safest mechanical practice.
-====== 2. Deburr the hole. ======+==== 2. Deburr the hole. ====
  
 Take a deburring tool (or a larger countersink bit) and gently twist it by hand (or at very low speed) around the top and bottom edges of the newly drilled hole to shave off the raised lip of metal. The drilling process extrudes a sharp, ragged "burr" (a raised ridge) around the entrance and exit of the hole. These burrs are razor-sharp and will slice your fingers when handling the part later. Deburring also ensures that if a bolt or screw is inserted, it will sit flush against the material without rocking. Take a deburring tool (or a larger countersink bit) and gently twist it by hand (or at very low speed) around the top and bottom edges of the newly drilled hole to shave off the raised lip of metal. The drilling process extrudes a sharp, ragged "burr" (a raised ridge) around the entrance and exit of the hole. These burrs are razor-sharp and will slice your fingers when handling the part later. Deburring also ensures that if a bolt or screw is inserted, it will sit flush against the material without rocking.
-====== 3. Remove the drill bit and clean it. Be careful—it may be hot. ======+==== 3. Remove the drill bit and clean it. Be careful—it may be hot. ====
  
 Use a rag (wearing no gloves!) to grip the shank (the smooth top part) of the bit, not the cutting flutes and loosen the chuck. Wipe it down with a rag soaked in a little oil or solvent to remove all metal swarf and cutting fluid. The cutting edges of the drill bit can reach over 100°C; touching the flutes directly causes instant second-degree burns. Cleaning the bit immediately is crucial because dried cutting fluid turns into a sticky, acidic varnish that corrodes the high-speed steel and dulls the cutting edges over time. Use a rag (wearing no gloves!) to grip the shank (the smooth top part) of the bit, not the cutting flutes and loosen the chuck. Wipe it down with a rag soaked in a little oil or solvent to remove all metal swarf and cutting fluid. The cutting edges of the drill bit can reach over 100°C; touching the flutes directly causes instant second-degree burns. Cleaning the bit immediately is crucial because dried cutting fluid turns into a sticky, acidic varnish that corrodes the high-speed steel and dulls the cutting edges over time.
-====== 4. Return it to its holder on the wall. ======+==== 4. Return it to its holder on the wall. ====
  
 Match the size (e.g., 10.0mm) engraved on the shank of the bit to the corresponding labelled hole of drill rack. Storing bits in their dedicated holder prevents them from rolling off the table and falling onto the concrete floor (which chips and dulls the cutting tip). It also ensures that the next user can instantly find the correct size, saving time and preventing people from using the wrong bit because they couldn't find the right one. Match the size (e.g., 10.0mm) engraved on the shank of the bit to the corresponding labelled hole of drill rack. Storing bits in their dedicated holder prevents them from rolling off the table and falling onto the concrete floor (which chips and dulls the cutting tip). It also ensures that the next user can instantly find the correct size, saving time and preventing people from using the wrong bit because they couldn't find the right one.
-====== 5. Clean the Pillar Drill. ======+==== 5. Clean the Pillar Drill. ====
  
 Using a stiff brush and a rag, sweep all metal chips off the drill table, out of the T-slots, and off the base plate. Wipe down the vertical column with an oily rag to prevent rust, and wipe any excess cutting fluid off the chuck. Using a stiff brush and a rag, sweep all metal chips off the drill table, out of the T-slots, and off the base plate. Wipe down the vertical column with an oily rag to prevent rust, and wipe any excess cutting fluid off the chuck.
  • equipment/metalshop/titanpillardrill/usinglargebits.1782756383
  • Last modified: 30 hours ago
  • by ralawrence