Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: thedoc on 26/07/2013 14:30:01

Title: Why does my door open more easily in summer?
Post by: thedoc on 26/07/2013 14:30:01

wayne jones  asked the Naked Scientists:
   I'm a long time listener (http://www.thenakedscientists.com/HTML/podcasts/), love the show

I own a small car workshop in Australia and it has 2 roller doors like you would normally see in a garage, and you roll them up by pulling on alarge chain.

Why is it that in winter when its cold its really hard on your hands and it all seems very difficult to pull the doors up, but in summer you can grab the chain and up it comes quite easily. It does not appear to be the door mechanism, so what's the science behind the cold hands.

Thanks

Wayne from Green Point Australia


What do you think?

Title: Re: Why does my door open more easily in summer?
Post by: CliffordK on 26/07/2013 20:14:48

I don't think I've noticed this with my barn roller doors. 

Are your doors made of wood or metal?  Wood doors can expand with moisture causing them to bind.

Another possibility is that you have grease in the bearings and tracks.  Grease, of course, becomes much higher viscosity in the winter, and with a large number of bearings, could be a big pain.

Title: Re: Why does my door open more easily in summer?
Post by: RD on 26/07/2013 20:26:12

Cold temperatures reduce muscle performance ... http://healthyliving.azcentral.com/effects-temperature-muscular-contraction-11504.html