Seek n’ Geek 6: Sliding closet door

For this week’s Seek and Geek, I’m looking at a sliding closet door, which is an interesting instance of a linear slide.

Sliding door – the doors are big and heavy!

First thing I noticed is that the door is guided from the top only – the bottom only has a plastic retaining clip to prevent the door from swinging too far out.


Taking a sneak peek into the rail above the door reveals that there are two sets of rollers holding up the door.

Plastic roller in extruded aluminum track

My analysis this week considers the pulling force on the door – how hard would one have to pull to cause the door to lift off one of the bearings and possibly jam? With my estimate for the weight of the door, it’s about 25 lbf [100 N], but because the door uses rolling element bearings it takes much less force than that (about 2 lbf) to get the door moving, so we never reach that level of force.