Which is stronger, Helical cut gears or Straight cut...
First of all I think we should defined what is meant by strength, IMO, this is the ability to transfer power without failure ( breaking ) from one gear to another ( input to output )
So...
A Helical cut gear is basically the same as a straight cut gear but on an angle ( pitch ) This pitch means there is a small overall increase in surface area, and also more than one tooth is in contact at any one time, compared to a Straight cut gear.
But...
On a helical gear only on a small section of a tooth is ever in contact, and at no time is any one tooth fully engaged, unlike a Straight cut where the faces are head on to each other and hence fully engaged.
Here's an amusing analogy...
Smack your forehead with the palm of you hand, hurts don’t it... This is similar to what happens when a SC gear engages.. If you repeatedly do this, instead of sounding like slap-slap-slap you would actually get a whine ( not from the person's head you are slapping !! lol )
helical cut gears are more like smacking your head with you hand, but at an angle, you hand sort of rolls across your forehead, the slap, is quieter, and the force is applied across the forehead.....
Which hurts more ?
Edited by GuessWorks, 12 April 2005 - 02:24 PM.