Longsheng

(4)Table drill (accuracy selection)

①Principle of operation: Clamped drilling machine, workpiece is brought forward to position drill.

②Basic advantage:

• High accuracy: guaranteed perpendicularity and depth uniformity.
• Energy-saving operation: Mechanical feeding, no handheld pressure needed.
• Stability: Avoid hole position drifting caused by hand shake.

③Typical applications:

• Metal parts machining (holes where high-accuracy positioning is required).
• Fine furniture manufacturing (mortise and tenon holes, location pin holes).
• Batch drilling operations (higher efficiency and consistency).
• PCB board drilling (small-sized bench drills).

④Weaknesses: Limited adaptability, workpiece size limited by table.

3. Rapid selection of tools: depending on the material and the need for exact matching

Target material	Recommended drilling tools	Applicable hole diameter range	Typical application scenarios Examples
Cork, plastics	Hand drill, hand drill, bench drill	< 1mm - 30mm+	Furniture assembly, modeling, plastic parts hole opening
Thin sheet metal (≤ 3mm)	Manual drills, bench drills	< 1mm - 13mm	Sheet metal processing, chassis drilling, metal brackets
Thick metal/cast iron	Trigger drills, hand drills (low speed), bench drills	< 1mm - 16mm	Equipment bases, steel connections, pipe flanges
Red/hollow bricks	Impact drills (impact mode)	6mm - 14mm	Wall hangings, switch box installations, lightweight brackets
Lightweight concrete blocks	Impact drills (impact mode), lightweight hammers	8mm - 16mm	External wall insulation fixings, small parapet foundations
Reinforced concrete/stone	Electric hammer (essential)	6mm - 40mm+	Load-bearing structure anchoring, through-beam casing, stone dry hanging
Tile/glass	Hand drill/impact drill (off impact)	4mm - 12mm	Bathroom installation, kitchen fittings, glass shelves
Batch precision holes	Table drill	< 0.5mm - 16mm+	Metal parts processing, PCB drilling, mold making

How to drill wood holes?

Wood hole drilling is one of the most common operations in woodworking and DIY. As simple as it seems to be, mastering the right techniques will avoid defects such as burrs, cracks, and drill bit deviation, and also make drilling more accurate, efficient, and safe. Here is a step-by-step operation manual:

1. Core tool selection

(1) Drilling tools:

• Hand drill (most commonly used): versatile and efficient, suitable for most cases.
• Hand crank drill: suitable for precision work (e.g., models, small holes) or power inconvenience.
• Bench drill: High accuracy, batch drilling, or deep hole drilling preferred.
• Impact Drill (not suitable): No impact function is required in wood drilling, but it is easy to damage wood fibers when starting it up.

(2) Drill selection (key):

• Woodworking drill: Specialized for wood, high efficiency, smooth hole wall. Common types:
• Center Positioning Drill/Twist Drill: Sharp spikes center tip, accurate positioning and anti-slip, applicable to small and medium holes (<12mm).
• Flat Drill / Spade Drill: Front end center tip + two wide blades on both sides, quick drilling, good chip removal but hole wall rough, applicable to big holes (>10mm) or through holes.
• Hole opener: center guide drill + ring saw blade, specializing in opening big size holes (>30mm, such as door lock holes, threading holes).
• Countersink drills: Making conical countersink holes in through holes to hide screw heads.
• Common twist drill (optional): can be used for small holes in softwood, but low efficiency, easy to burr, hardwood or large holes not recommended.

2. Operation steps in detail

(1) Preparation

• Measuring and marking: The center of the hole can be marked accurately with a pencil and ruler, the crosshairs are easier to line up.
• Secure the workpiece: Clamp wood tightly to the workbench with a G-clamp, vise, or fixture. Hand-held operation is easily deflected and dangerous!
• Select drill bit: Select the appropriate woodworking drill bit for the hole diameter and accuracy, place it in the drill chuck, and secure.
• Put on protective gear: Goggles (to prevent wood chips from flying into the eyes), dust mask (to prevent inhaling fine dust), and avoid loose clothing/gloves (to prevent entanglement).

(2) Drilling Techniques

Identify the starting point:

• Align the drill point with the center of the crosshairs.
• Hand Drill/Hand Crank Drill: Place the drill bit firmly before drilling and use the center tip to make tiny indentations (locating pits) on the surface of the wood to prevent slipping. 

Control the angle:

• Vertical drilling: Keep the drill bit exactly vertical to the wood surface (verify with the aid of a straight edge). Drilling at an angle will result in crooked holes, bent bits and even breakage.

Control RPM:

• Softwoods (fir, pine): Medium to high speed (e.g. 1500-2000 rpm for hand drill).
• Hardwoods (teak, oak), laminates, plywood: low to medium speed (800-1200 rpm) to reduce the risk of scorching and burrs.
• Large holes (>10mm) or openers: Slower speeds to avoid too high a torque causing loss of control.

Feed strength:

• Apply light pressure at first, then feed smoothly and evenly once the bit is fully bitten into the wood.
• Avoid over-pressure: Excessive pressure will result in overheating of the bit, hole wall chipping or chipping of the wood at the rear.

In deep hole drilling, remove the drill bit every 10-15mm to remove wood chips in the drill slot to prevent clogging and overheating.

(3) Special Scenario Handling

Drilling through holes:

When the drill bit is about to come in, reduce the pressure significantly or discontinue, turn the wood over and reverse the drilling confluence from the rear, which can avert the wood bursting at the exit.

Or pad a scrap wood board piece under the work for the safety of the drill bit and table while drilling through.

Drilling deep holes:

Use a long drill bit and strictly follow the "exit chip removal" principle.

Marking the drill depth: Use tape on the drill to mark the intended depth.

Drill large holes (>30mm):

Either use a hole opener: low-speed drill into the center guide to position the hole, then advance the circular saw blade evenly forward.
 
Or sequential drilling: initially drill using a small bit, then gradually use a larger bit to enlarge the hole.

Hardwood/Laminate:

Pre-drill pilot holes with a small drill bit (e.g. 3mm) and then change to a target drill bit for reaming, with less deflection and less burring.

Thin wood panels:

Scrap board must be padded underneath to prevent tearing when drilling through.

3. Common problems and solutions

With these hints in mind, you'll be able to drill spotless, clean holes, whether furniture making, laminate or DIY woodwork installation!

How to drill holes in metal?

Metal hole drilling is a useful skill in metalwork, machine repair, and home renovations. Metal is hard and a good conductor of heat relative to wood, and thus careless handling can easily result in burned drill bits, crooked holes, and even splash cuts to workpieces. With the right skills acquired below, you will safely and efficiently drill accurate metal holes!

1. Preparing core tools and consumables

(1) Selection of a drilling tool:

• Bench drill (optimal): provide the greatest stability and vertical accuracy, especially for heavy metal or accurate machining.
• Electric drill (standard): versatile and convenient, need to be used in conjunction with a drill stand or guide to improve accuracy (easy to transport using bare hands).
• Magnetic drill (professional): for steel frames of large diameters, adsorption of workpiece + automatic feeding, fast drilling of large holes.

⚠️ Impact drills are prohibited: the impact function at once destroys the cutting edge of the metal drill!

(2) Drill selection (the success or failure factor!)

Material:

• High Speed Steel (HSS): Inexpensive and average, for mild steel, aluminum, copper and other soft metals (thickness <5mm).
• Cobalt high-speed steel (HSS-Co, e.g., M35): 5%-8% cobalt, heat resistance ↑↑, capable of drilling stainless steel, alloy steel, cast iron.
• Drill carbide: very hard and abrasion-resistant, best in hardened steel of high hardness, wear-resistance cast iron, but highly brittle and prone to chipping.

Geometric angle:

• 118° drill tip angle: general-purpose angle, a compromise between penetration force and life.
• 135° drill tip angle: sharper, reduced axial force, good for stainless steel, hard steel, anti-hardening.
• Flute design: High-performance drills with polished spiral flutes or chipbreaker flutes to maximize efficiency in chip removal.

(3) Auxiliary consumables

• Cutting fluid/lubricant: Absolutely necessary! Cooling + lubrication + extend the drill life (suggested: sulfurized cutting oil, special metal drilling paste).
• Center punch/specimen punch: Precise placement in order not to have drill bit slipping.
• G-clamp/vise: rock-solid holding of the workpiece!
• Goggles + cut-resistant gloves: prevent people from getting injured by metal chips.

2. Standardized operation process

(1) Safety preparation stage

• Clamping the workpiece: use a vise or a fixture to clamp the metal firmly on the worktable to avoid shaking.
• Protection: Goggles (anti-flying chips), cut-proof gloves (anti-burr cutting), no common gloves (anti-contact).
• Clean up the surface: Remove oil, rust, and make the point of drilling even (use a file to level the surface if not even).

(2) Precise setting and starting drill

• Center marking of the hole: Scribe needle + steel ruler to accurately mark center of the hole at the intersection of crosshairs.
• Play positioning pit: use the center punch to align at the center of the cross, hammer to drive the depth of > 0.5mm pit (absolute anti-slip key!). Punching the pit
• Clamping drill bit: Select appropriate drill bit size, ensure that the drill shank does not vibrate in the drill chuck, and clamp it with full torque.

(3) Drilling parameter control

Parameters	Operating Points
Speed	​​Hard metal (steel, stainless steel): low speed (300-800 RPM) Soft metal (aluminum, copper): medium speed (1000-2500 RPM) The larger the hole diameter, the lower the speed (e.g.: 500RPM for a 10mm hole)
Feed force	Maintain a steady and continuous pressure to avoid sudden changes in weight. Drill thick metals in stages: small hole → medium hole → target hole (e.g.: 3mm → 6mm → 10mm)
Cooling and lubrication	Apply cutting fluid continuously throughout the process!  Add fluid every 2-3mm of drilling and exit, and the drill temperature must not exceed 150℃ (limited to being able to touch by hand).

 (4). Key Operation Tips

• Vertical drilling: align the tip of the drill bit with the locating pit, start the motor and test drill with light pressure, make sure there is no slippage and then increase the force at a constant speed.
• Discharge management: Every time the drill bit is drilled into a depth of 2-3 times the diameter of the drill bit, completely withdraw from the drill to remove iron chips from the spiral groove (to prevent clogging and burning of the drill).
• Penetration phase: Reduce the force by 50% when the drill is about to penetrate, to avoid metal edge tearing or drill bit jamming and chipping.
• Deep hole treatment: Drill in sections + retreat chips diligently, use extended drill bit or gun drill (depth to diameter ratio >5).

3. Drilling strategies for different metals