Beveled rails

[sflogging]

What is the main benefit of having beveled rails on a surfboard? I noticed that Stewart Redline 11 longboard has beveled rails, while their redline pro did away with the beveled rails, and was wondering what advantages/disadvantages there are with the beveled rails.

Thanks!

[BoMan]

Here is information from one of my favorite sites - Surf Science. Chine or Beveled Rails are considered “hard.”

Rail Design
The rails extend from the nose of the board to the tail. They will be thicker near the center of the board and narrower towards the nose and tail. Depending on the shape, a rail will help us make turns through the water, catch speed, and provide more flotation. There are different ideas regarding which rails are right for which conditions, but generally speaking, there are two types of rail design: soft and hard. Soft rails are rounded with no hard edges. The transition from the rail to the bottom of the board is very smooth. A hard rail (also called a down rail) is more squared off, sloping down in a more distinct manner and may form a corner or edge with the bottom.

Performance
Harder rails best suit the modern shortboard. They will knife into the water's edge easier, making it plane faster and turn quicker. This is because that hard edge, especially in the tail, allows the water to abruptly release from the board's rails, creating more maneuverability and speed. If the surfer is so inclined to use his rails rather than rely heavily on the fins, it also allow for long drawn out rail turns. On the downside, hard rails with edges make pivotal turns more difficult. These rails are generally better in large, steep and hollow conditions. The hard edge allows the board to gain a firm hold in the wave and remain stable at faster speeds. The compromise is in rail volume. Even a shortboard must have thicker, softer rails in the center of the board if it is to float the surfer. The nose and tail volume will remain thinner and harder for speed and performance.

If hard rails are better suited for high performance shortboards, then softer rails are most common on longboards and small wave shortboards. Soft rails are more forgiving, meaning you are less likely to catch an edge and bog the rails into on sloppier wave face. The downside is they produce enormous drag and will not turn as easily on the rail in larger surf. In contrast, soft rails will allow a surfer to take full advantage of a fin's turning radius. Turning from near the tail should be much quicker and require less effort in smaller surf. Fuller, softer rails will help you paddle into more waves and also help you maintain speed in the flats of the wave. Although full rails are also more difficult to sink, this will translate into more stored energy during a turn and the release of that energy coming out of the turn (commonly known as drive).

Most surfers are better off with a medium rail. This should provide the advantages of both a hard and soft rail, while downplaying the negatives. A medium rail will produce a fast board in steep waves, while still allowing the freedom to use the fins creatively in surf that isn't so steep. You should feel fairly stable with medium rails and be able to turn in a tight radius. The most common example is a "tucked under rail". This is a round rail with a tucked under edge that will provide some release, but also offers a smooth and forgiving ride.

http://www.surfscience.com/topics/surfboard-anatomy/rail/ignore-the-rail-at-own-risk

[waikikikichan]

If you understand the benefits of a "wing-swallow" or a "Bump-Squash" in tail design, then you kinda sorta get what a bevel/chine on a rail does. It's just another release point. The water shears off the edge instead of flowing along the curve.
Do most people like them ? I don't think enough people have ever tried beveled rails to know. I love(d) them, I learned on a borrowed Ben Aipa that had "Star-Beveled" rails, that are even more radical like a concave than a chine. Helped me to get leaned over. BUT that's maybe why the Stewart Pro ( riders ) don't need bevels on their boards. Just like motorcycle tire profiles, some like the consistent feel of a round profile versus a more triangle profiled tire. The Stewart Hydrohull has chines. The Walden Magic has chines. I've ridden them both and liked them.

[tradiprone]

What is the main benefit of having beveled rails on a surfboard? I noticed that Stewart Redline 11 longboard has beveled rails, while their redline pro did away with the beveled rails, and was wondering what advantages/disadvantages there are with the beveled rails.

Thanks!

Hello sflogging
Allow me to share a bit of my experience with a beveled rail board-Walden Magic 10'-, vs a softly tucked under rails Bic Pearson Noserider.
Bear in mind that although both boards are similar in basic dimensions (10'×23.5"×3.25"), volume (96 vs 90 Liters respectively), rounded nose/squash tail, that's where similarities end.
The beveled railed, single to double concave Walden is heavily rockered, more in the tail than in the nose, compared to the belly bottomed Bic.
I address the similarities and differences between these boards because analyzing beveled rail behavior happens in context with other design features. I feel it's very hard to isolate the effects of beveled rails between these two boards even with the features they both share.
The only way I see this comparison can be made vis a vis is having two boards shaped exactly the same, one with beveled rails and the other with a different rail design.
Then, the one with beveled rails will function better with the other design features it matches better, such as rocker, bottom, etc., biasing one's opinion towards it.

Back to my two examples, the beveled railed Walden likes to turn more in the surface of the water while the softly tucked under Bic is more involved in the wave's power flow and pivots easily when stalled.
In other words, the Walden likes speedy cutbacks and bottom turns, while the Bic prefers stalls, pivoty repositioning and flowing down the line.
Another important difference is upon take off: The Walden prefers later takeoffs, going from paddling speed to light speed while the Bic wants progressive speed increase and very early wave catch. And beveled rails, working as hard rails, help to achieve planing quicker.
Hope my comparison helps you to envision beveled rails as a part of a whole surfboard design, where they function as part of a set of features intended to work together.

Be well, Happy New Year!