How An “Improvement” To The Phillips Screw Made DIY Harder
The Screwy Secret That Almost Nobody Knows
This past weekend I went to pick up a bookshelf from someone in the neighbourhood, and for the millionth time ran into a problem I’ve been aware of for ages and nobody else seems to be familiar with: Posidriv screws and Phillips screwdrivers. A few years ago we moved into an apartment where almost every screw I encountered seemed to be stripped! Some of them were so bad that I eventually had to bring in a professional to remove them, and he taught me to identify the different screw types…
A brief history
Once upon a time, there were Phillips screws (or “star”, to some of us laypeople) and Phillips screwdrivers, and everyone was happy. Then, in 1962, an ingenious patent was secured by the Phillips Screw Company and the American Screw Company: a subtle improvement to the famous Phillips screws. Officially called “Pozidriv”, which is short for “positive drive”, the new screw design had parallel flanks which enable an appropriate pozidrive screwdriver to apply more torque and also provides a sturdier grip. As an added bonus, Phillips and Pozidriv screws and screwdrivers look almost identical, and using one type’s screwdriver on the other is a sure-fire way to strip both screws and screwdrivers alike.
