Hand ToolsDriver
Screwdriver Set
Blades ground to the width and thickness of a slotted head, in assorted sizes. Fit is the whole question: a blade that is close but wrong damages the screw.
What it does
- Driving slotted head screws
- Final tightening of small screws by hand
- Working where a powered driver is too heavy or too coarse
Fasteners it fits6 standards specify slotted
All standardsMatched on the drive form recorded against each standard, not on the tool's own claims — so this list changes when the fastener data changes, not when this paragraph does.
What to look forthe judgement calls, before the spec sheet
- Blade width should fill the slot. A narrow blade concentrates the load on the slot's interior and cams out, which is what rounds a slotted head.
- Blade thickness matters as much as width and is rarely quoted. A blade that is too thin bottoms in the slot and cannot transmit torque at all.
- The handle diameter sets the torque you can apply by hand. For cheese head and pan head screws that is usually the intent; for anything larger, a driver bit in a bit holder is better.
Misuse and safetythe ways this tool causes rework
- Do not use a screwdriver as a chisel, a pry bar or a scraper. The blade is heat-treated for torsion and a bending load takes the temper out of it at the tip.
- A slotted head offers one line of engagement. Once it is chewed, the screw has to come out by other means, so fit matters more here than on any other drive.
Frequently asked questions
Why does my screwdriver slip out of the slot?
Almost always a blade that is too narrow or too thin for the slot. The load lands on the slot's internal corners instead of its walls, and the tip climbs out.
Is a slotted drive still specified anywhere?
Yes, mainly where the screw is adjusted rather than assembled, where a slot can be turned with a coin or a small bar, and in older equipment. Several standards in this database are slotted head, and their pages list the dimensions.