Removing one way screws from window locks

February 17, 2009
Window lock with one way screw

All the old window locks in our house make use of one way screws. Basically, the groove on the screw head is designed with a sharp groove edge for screwing in, and a gentle slope offering no grip on the edge for unscrewing.

Personally, I’m sceptical of their security value. My parents house was burgled when I was growing up and the ease with which people can kick through a deadlocked door left a lasting impression on me. Blunt force trauma on window locks would be highly effective and much more direct than taking the time to unscrew the locks.Failed drilling attempt

My initial removal plan was to drill out the old screw, which is a pearl of wisdom planted in my head from years of watching heist movies and having legend-in-our-own-lunchtime handyman conversations with friends.

After 15 minutes of drilling on a single lock, I began to suspect that my drill bits passed down over the years like family heirlooms may not be sharp enough to do the job effectively. Visiting Bunnings for new tool parts is always tempting, but there had to be an easier way.UnscrewHacksaw new groove

I highly recommend using a hacksaw to cut a new groove in the screw. The window locks are raised from the window itself, making it easy to avoid damage. Removing all the locks only took a few minutes after I adopted this technique.