| West Wight Potter Owner's Home Port ____________________________________________________________________________________ |
Running downwind before a fresh breeze can be an exhilarating experience in a small sailboat. You watch your
headsail swell with wind; you admire its pretty shape and wonder why you didn’t splurge on that “color stripe”
option. It almost seems like your boat is being pulled toward the horizon by some invisible, benevolent hand.
But then, amidst your sailing bliss, your eye wanders to your boom. That boom has always been your friend. It
has offered you a stable handhold when you needed it. It dependably holds your mainsail clew. Sometimes, you
even throw a tarp over it and it gives you shelter. But not now. Now, it’s not your friend. Running downwind, it
can scare you; it can hurt you.
I was sailing my ’95 P-15 Tetra on Corpus Christi Bay on a fabulous June morning and Jimmy Buffett was
singing to me through the “shower radio” in my cockpit. I’d traveled about five nautical miles that morning, mostly
on a gentle broad reach. Up ahead, I knew that I had to turn downwind and navigate a tricky pass that provided
me with a nifty shortcut into the Ship Channel. When I felt like I’d arrived at the optimal turning point, I steered
Tetra dead downwind and put her on a run. That’s when I noticed that the wind had really picked up and I had
all my sail up. I also noticed that I was in very shallow water and had short steep rollers behind me that were
trying to sneak through the same shortcut. I pondered my predicament. Then, I accidentally jibed.
I was sitting there on the starboard side of the cockpit and, with horror, watched my boom as it slammed over
and joined me on that side of the boat. Tetra suddenly noticed that she now had 220 pounds of captain, the
mainsail, two full ice chests, two batteries, an anchor and a five gallon fuel can all on the starboard side. As I
scrambled for the port gunwale, I wondered if there might be a better way to manage my boom’s motion in
downwind points of sail.
So, over the winter, I decided to add a boom brake to Tetra. I spent some time at a big sailboat show looking
over boom brake and preventer options and they just seemed huge in size and cost. The target market for boom
brake manufacturers seems to be boat owners with forty feet of waterline. If I was going to install one of these
things, I’d have to build it myself. So, I began sketching out cheaper, smaller options and ultimately built a
system from the technology that my Boy Scout sons use to rappel down cliffs.
The local hiking/climbing store sold me a strong, aluminum “Figure 8” descender for about $14. This descender
is a piece of rappelling equipment that allows climbers to slide down a rope at manageable speeds, by creating
friction as the rappelling line twists through the device. I mounted the descender just abaft of my boom vang.
(See Photo 1) Because of the forces that it might potentially have to withstand, I attached it using a stainless
steel bail and a strong shackle. Rivets just will not give you the strength needed.
Photo 1
In my installation, I pass a single line through the descender. The two ends run through blocks and then
terminate alongside the companionway. The line I use is 3/8” Samson XLS yacht braid and it is the black and
white cordage that you see in the photos. Photos 2 and 3 show you how the lines are routed. The blocks are
connected to the cabin roof using strong pad eyes, backed with large stainless fender washers. The brake line
then passes through a pair of cam cleats on either side of my companionway hatch.
Photo 2 Photo 3
Okay, this is how it works. When the brake line is loose (see Photo 4), the boom is free to swing as normal.
This is how I will sail on points of sail forward of the beam. By tightening the line (Photo 5), the boom’s motion is
slowed in proportion to the tension I apply. When cinched down completely, the brake becomes a preventer that
tightly holds the boom in one position. Not only can I now reduce the chance of accidental jibes, but I can now
experiment with “sailing by the lee”.
Photo 4
Photo 5
If you decide to do this, you may need to experiment some to determine the optimal location of your blocks and
the size of line to use. If you are installing this system on a P-19 or Sanibel, you may need to create more friction
than I need on my P-15. You might add a wrap around the descender or even run a double line through the
system.
Testing your boom brake can be easily performed in your driveway. Simply shove the boom around and tinker
with your lines until you get the resistance that you need. Heck, let your kids help. Dare them to knock you off
the boat with the boom. They’ll happily play that game for hours. Trust me.
A boom brake and preventer can never completely remove all of the challenges created by running downwind.
And, you need to use it with caution. A boom locked on the “wrong side” of the boat can create as many
problems as an accidental jibe, so practice often and use with caution. But, hopefully, an increase in the control
of your boom’s movement will remove some of the stress that comes with this challenging point of sail. And, isn’t
stress-free sailing one of the reasons you bought a Potter?
John Turpin
John lives in Edmond, OK and has been sailing West Wight Potters for many years. He sails his P-15, Tetra, in
local lakes and along the Texas coast. For more information on John’s extensive restoration of Tetra and the
adventures they share, visit his website at www.tetra-sail.com.
headsail swell with wind; you admire its pretty shape and wonder why you didn’t splurge on that “color stripe”
option. It almost seems like your boat is being pulled toward the horizon by some invisible, benevolent hand.
But then, amidst your sailing bliss, your eye wanders to your boom. That boom has always been your friend. It
has offered you a stable handhold when you needed it. It dependably holds your mainsail clew. Sometimes, you
even throw a tarp over it and it gives you shelter. But not now. Now, it’s not your friend. Running downwind, it
can scare you; it can hurt you.
I was sailing my ’95 P-15 Tetra on Corpus Christi Bay on a fabulous June morning and Jimmy Buffett was
singing to me through the “shower radio” in my cockpit. I’d traveled about five nautical miles that morning, mostly
on a gentle broad reach. Up ahead, I knew that I had to turn downwind and navigate a tricky pass that provided
me with a nifty shortcut into the Ship Channel. When I felt like I’d arrived at the optimal turning point, I steered
Tetra dead downwind and put her on a run. That’s when I noticed that the wind had really picked up and I had
all my sail up. I also noticed that I was in very shallow water and had short steep rollers behind me that were
trying to sneak through the same shortcut. I pondered my predicament. Then, I accidentally jibed.
I was sitting there on the starboard side of the cockpit and, with horror, watched my boom as it slammed over
and joined me on that side of the boat. Tetra suddenly noticed that she now had 220 pounds of captain, the
mainsail, two full ice chests, two batteries, an anchor and a five gallon fuel can all on the starboard side. As I
scrambled for the port gunwale, I wondered if there might be a better way to manage my boom’s motion in
downwind points of sail.
So, over the winter, I decided to add a boom brake to Tetra. I spent some time at a big sailboat show looking
over boom brake and preventer options and they just seemed huge in size and cost. The target market for boom
brake manufacturers seems to be boat owners with forty feet of waterline. If I was going to install one of these
things, I’d have to build it myself. So, I began sketching out cheaper, smaller options and ultimately built a
system from the technology that my Boy Scout sons use to rappel down cliffs.
The local hiking/climbing store sold me a strong, aluminum “Figure 8” descender for about $14. This descender
is a piece of rappelling equipment that allows climbers to slide down a rope at manageable speeds, by creating
friction as the rappelling line twists through the device. I mounted the descender just abaft of my boom vang.
(See Photo 1) Because of the forces that it might potentially have to withstand, I attached it using a stainless
steel bail and a strong shackle. Rivets just will not give you the strength needed.
Photo 1
In my installation, I pass a single line through the descender. The two ends run through blocks and then
terminate alongside the companionway. The line I use is 3/8” Samson XLS yacht braid and it is the black and
white cordage that you see in the photos. Photos 2 and 3 show you how the lines are routed. The blocks are
connected to the cabin roof using strong pad eyes, backed with large stainless fender washers. The brake line
then passes through a pair of cam cleats on either side of my companionway hatch.
Photo 2 Photo 3
Okay, this is how it works. When the brake line is loose (see Photo 4), the boom is free to swing as normal.
This is how I will sail on points of sail forward of the beam. By tightening the line (Photo 5), the boom’s motion is
slowed in proportion to the tension I apply. When cinched down completely, the brake becomes a preventer that
tightly holds the boom in one position. Not only can I now reduce the chance of accidental jibes, but I can now
experiment with “sailing by the lee”.
Photo 4
Photo 5
If you decide to do this, you may need to experiment some to determine the optimal location of your blocks and
the size of line to use. If you are installing this system on a P-19 or Sanibel, you may need to create more friction
than I need on my P-15. You might add a wrap around the descender or even run a double line through the
system.
Testing your boom brake can be easily performed in your driveway. Simply shove the boom around and tinker
with your lines until you get the resistance that you need. Heck, let your kids help. Dare them to knock you off
the boat with the boom. They’ll happily play that game for hours. Trust me.
A boom brake and preventer can never completely remove all of the challenges created by running downwind.
And, you need to use it with caution. A boom locked on the “wrong side” of the boat can create as many
problems as an accidental jibe, so practice often and use with caution. But, hopefully, an increase in the control
of your boom’s movement will remove some of the stress that comes with this challenging point of sail. And, isn’t
stress-free sailing one of the reasons you bought a Potter?
John Turpin
John lives in Edmond, OK and has been sailing West Wight Potters for many years. He sails his P-15, Tetra, in
local lakes and along the Texas coast. For more information on John’s extensive restoration of Tetra and the
adventures they share, visit his website at www.tetra-sail.com.
Taming the Boom with a Brake
by John Turpin
by John Turpin
Copyright 2009 John Turpin
