Pozidriv screwdrivers are often designated using the letters "PZ" followed by a size code of 0, 1, 2, 3, 4 or 5 (in order of increasing size). The numbers do not correspond to nominal screw size numbers. PZ1 is normally used on screw diameters from 2-3mm, PZ2 from 3.5-5mm and PZ3 from 5.5mm to 8mm.
Pozidriv screw symbol and screwdriver tip with parallel flanks. According to ISO standard, the two cross-head screwdriver types are designated as PH for Phillips and PZ for Pozidriv screws.
A Phillips bit fits in a Pozidriv screw head, but it will most likely cam out before the fastener is fully tightened. This can damage the fastener (and it may explain why cup hinges seem to loosen up so quickly). A Pozidriv bit does not fit in a Phillips screw head.
Phillips screwdrivers fit in Pozidriv screws, and can turn them. However, they are liable to slippage, and can damage the screw. Pozidriv screwdrivers, on the other hand, do not fit Phillips heads. If you try, you'll probably fail, and you'll probably damage your screw.
The smallest of Pozidriv sockets, PZ-0, is frequently used in screws to fasten small components, such as electronics, while the largest of the commonly seen Pozidriv sockets, PZ-4, is used in frame anchors, such as used for fastening windows and doors to masonry.
The advantage of Torx® is the better drive, requiring less pressing force than with the Pozidriv impression. The risk of damaging the screw is lower because the bit less easily shoot from the head. Torx® know impressions in addition, a larger variation in the size of the bits.
Pozidrive Bits
This design also provides a greater driving surface and decreases wear. They come in three main sizes – #1, #2 and #3 (#2 is again the most common).
As an improvement on the Phillips drive style, the main benefit of using the Pozidrive is the increased torque without the increased risk of cam-out. Pozidriv screws can handle significantly more torque on the fastener recess than a Phillips drive can.
Increased Torque Capacity
One of the primary optimisations of the Pozi drive was in its improved ability to be used in self-tapping applications, which require significantly increased torque to drive the screw into an unprepared hole.
Choose the bit size that fills the screw head entirely. A bit that is too big or too small will not seat properly, and you'll end up with a stripped screw. The chart below outlines the correct screwdriver bit for the most popular screw gauges.
Pozidriv screwdrivers are often designated using the letters "PZ" followed by a size code of 0, 1, 2, 3, 4 or 5 (in order of increasing size). The numbers do not correspond to nominal screw size numbers. PZ1 is normally used on screw diameters from 2-3mm, PZ2 from 3.5-5mm and PZ3 from 5.5mm to 8mm.
Cross screw heads used in IKEA products are often Pozidriv screws, which are commonly used in Europe. When assembling IKEA furniture, you can use a screwdriver for the cross (Phillips) screw heads commonly used in Japan.
The right tool is a JIS screwdriver, which just fits better in a JIS screwhead and is designed to let you apply more torque than a Phillips driver. Sometimes a dot will let you know you're dealing with a JIS head.
Common options include flathead, Phillips, Robertson, or Torx slots, though you may need to have a screw on hand to compare the slot size to the screw notch.
The Robertson, or square-drive screw, which only recently gained acceptance in the United States, has been favored in Canada for decades.
What is the best type of screw drive? Many would say the Phillips drive screw, characterized by a pointed tip, tapered flanks and rounded corners. The Phillips screw is more commonly used than a slotted screw because it's more stable with four contact points.
Some Small Screws Require Different Bits
Certain types of screw heads work better for certain types of bits. For example, very small screws, such as those you find in your glasses or on electronic devices, don't require a high amount of torque. In these cases, a screw head like flathead or Philips works just fine.
A cheese head screw is one with a cylindrical head. “Cheese head” screws are defined by their head type. The cheese head has cylindrical sides with a flat disc top and a flat bearing surface. The head height is approximately half of its diameter and typically features a slot drive.
Phillips screwdriver bits and sets
Phillips screwdriver bits are among the most widely used of all types today.
Carbide: The hardest and most brittle of the drill bit materials, it's used mostly for production drilling where a high-quality tool holder and equipment is used. It should not be used in hand drills or even drill presses. These bits are designed to drill into the hardest materials.
A: PH is short for Philips head, whereas PZ is short for pozidrive. PH screws just have a cross slot on the head; PZ look similar but have additional lines between the slots.
What exactly is a tamper proof Torx bit and what purpose does it serve? Simply put, they are Torx (or Star) screwdrivers that have a round hole in the middle to match the Star/Torx screws that have a pin. Tamper proof screws are usually inserted so they cannot be interfered or changed easily.