[Greenthumb]

I’m looking for info on cushion profile dynamics to understand the broad cushion profile used with snooker tables. I play on a new Riley Aristocrat table which has a broad cushion profile similar to the L77 type. It appears from youtube videos, that a similar broad cushion profile is used by other snooker table manufacturers as well. I've read that pool tables typically use the K-66 profile, and carom tables use the K-55 cushion profile. In contrast to these narrow nose profiles, the Riley table cushions I’m familiar with have a nearly 1/2 inch width ball contact dimension, rather than the narrow nose common to pool and carom tables, and as I’ve experienced on a Brunswick snooker table.

I’ve made some approximate measurements on the Riley Aristocrat table which point to the lower part of the nose being near 0.5D, and the upper part being at 0.7D, where D is the snooker ball diameter, 2 1/16 in. It seems that most or all of this broad nose is in contact with the ball when it strikes the cushion. I would appreciate thoughts on why snooker tables benefit from use of such cushions, or where I might get information on the physics behind this design.

[HurdyGurdy]

I don't have an answer for you as to why but the Riley Aristocrat that I play on has the same rail profile as you've mentioned (also has the steel cushion blocks). If I were you I would register at SnookerForums.com and ask the same question.