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Roller Reefing the Main

PostPosted: Sun Jun 13, 1999 12:00 am
by Guest
I'm new to the O'Day Daysailer, and am learning to sail by trial and error. I'm told that I can roll up the sail on the boom creating a smaller sail for those days when the wind is too strong. I'm not sure that I understand all I know. Can anyone help?

Mike Hill (

PostPosted: Sat Jun 26, 1999 12:00 am
by Guest
Mike: You can roller reef the main if you have a reefing claw. This equipment slides down the boom, and the boom then spins on the gooseneck, allowing you to roll the sail inside the claw. There is a block on the bottom of the claw that will allow you to rig up the main sheet. I can give you more detailed instructions if you would like.
Jennifer, BWSS.

Blue Waters Sailing School (

PostPosted: Sat Jun 26, 1999 12:00 am
by Guest
I need more info. What is a claw? Is it something someone could make? Any Diagrams?

Mike Hill (

PostPosted: Wed Jun 30, 1999 12:00 am
by Guest
Mike: Here are the instructions we give to our students. They are a bit simplistic, but I hope you find them helpful. Also, see the message thread titled 'reefing claws: are there any out there?"
"The 17' O'Day Daysailors use roller reefing for the mainsail. The mainsail is rolled up onto the boom. The mainsheet is trimmed from a block in the center of the boom. If we just rolled up the sail, the block and the mainsheet would also get rolled up and we could not use them. We use a "reefing claw" to hold the mainsheet block to the boom. This claw is placed in the center of the boom, and the sail is rolled under it. The gooseneck has a square key that is held in the forward end of the boom by a spring. This arrangement allows you to roll the boom. The mainsheet blocks are attached to the end of the boom by a tang and a pin that allows the boom to rotate.
1. Remove the mainsheet from the blocks on the centerboard trunk and the middle of the boom. Remember to untie the stopper knot from the end of the sheet. Remove the block from the boom and put in a safe spot- the cabin shelf or the sailbag.
2. Place the reefing claw over the aft end of the boom and slide it to about the center of the boom.
3. Tie the forward line from the claw around the mast below the gooseneck. Use a round turn and two half hitches.
4. Tie the aft line from the claw to the mainsheet block attachment at the aft end of the boom. You want these lines to not get wound up in the sail as you roll the sail onto the boom.
5. Lead the mainsheet through the block in the claw and through the block on the centerboard trunk. Remember the stopper knot!
6. Raise the mainsail, but do not cleat it. Have one person tend the halyard. They will ease the halyard while the other person rolls up the sail.
7. Begin rolling the sail onto the boom. Pull the boom aft to release the gooseneck. Work carefully to roll it neatly and keep the sail under the claw tie down lines. Keep pulling the sail aft to prevent it from getting wound up in the gooseneck. If you aren't careful, the sail will prevent the gooseneck from locking after reefing. The halyard tender should keep a light tension on the halyard. This person can also help keep the gooseneck rotating.
8. After you have rolled up enough sail, make sure the boom has rotated so that the square key on the gooseneck will fit into the boom. Push it all back together.
9. The roller reefing of these sails allows the aft end of the boom to hang pretty low. You can raise the boom up by raising the whole sail. The gooseneck may be a foot higher on the mast than it is when the sail is not reefed."

Blue Waters Sailing School (

PostPosted: Thu Jul 01, 1999 12:00 am
by Guest
Jennifer and Ann,
Thanks for the great instructions on reefing and your patience in maintaining this thread for us beginners. I have some questions regarding the forward and aft lines. The "build it yourself" reefing claw described in the other message thread "reefing claws: are there any out there?" does not have provisions for the lines, where do they attach to the claw? Is it possible to attach the forward and aft line after the sail is rolled to both the claw and boom/mast?

Thanks Again,

Bob Wilson (

PostPosted: Thu Jul 01, 1999 12:00 am
by Guest
The purpose of the fore and aft lines is to keep the claw in place. You need to attach those lines, as well as the mainsheet, before you reef. Otherwise, the claw will tend to get rolled into the sail.
The case of the do-it-yourself alternative seems to be different. You don't need the tension of fore and aft lines to keep it in its place on the boom.

Blue Waters Sailing School (

PostPosted: Mon Jun 14, 2004 5:31 pm
by Guest
I have the roller reef set up but I cannot figure how to rig control of the main once the rolle is started. does it go to the end of the boom or to the roller

ed oconnor (

PostPosted: Wed Jun 16, 2004 11:12 am
by Guest
Ed you need a device called a reefing claw. It slides over your main after it's rolled. You then attach the main sheet to it. I had a couple, but gave them away. I don't know where you can get them. Somebody else on the list may be able to help you.

Ed Hutchinson

Ed Hutchinson (

PostPosted: Sun Aug 15, 2004 9:44 pm
by Guest
Ed, you may purchase a reefing claw at the folowing website. ... temap.html

I am just learning to sail a 1973 Oday Mariner. It is alot of fun but can be daunting when the wind picks up. I finally discovered that the main which has no reef points can be roller reefed. However it did not come with a reefing claw. Today I made one of the cloth reefing setups described in the other thread on reefing claws. It worked great! I made one 3 feet long x 12 inches wide with a steel ring sown into the end. I did not use sailcloth since I didn't have any instead I used a heavy almost canvas material. I will probably make another one 6-12 inches longer to allow another turn on the boom which will position my main sail slugs to fit the mast track better. It may take a little trial and error to get the right length for a particular boat but it does work!

One concern I have with the reefed sail is that there seems to be alot of pressue on the sail at the aft end of the boom . Is this normal?

Steve (

PostPosted: Wed Aug 18, 2004 2:28 pm
by Guest

Went to the website you mentioned ( and indeed they have reefing claws. I e-mailed them and they were very prompt in answering my correspondance. I think I will go ahead and order one of the claws ( the bigger of the two). They are a bit pricey, but if it works then so much the better. I will post my results after I receive the reefing claw and set it up on my daysailer. There may be many others interested in p;urchasing a reffing claw. Thanks again for the tip.


Gary L. Britton (

PostPosted: Tue Nov 30, 2004 9:50 am
by texaspsdx

You don't need a reefing claw

PostPosted: Mon Sep 06, 2010 11:15 am
by Helderberg Complainer
If you don't have a reefing claw, just unshackle the mainsheet from the boom,and attach a line to the boom where the main sheet was shackled. As you slack the halyard roll the main sail onto the boom, rolling the line with it. When you have reefed as much as you want to, lock the boom back in place by letting it spring forward. Then use the line to tie the mainsheet to the boom. (You will have to experiment to determine how long a line to use, depending on how much you want to reef. Tighten the halyard and you are set. This is just as convenient as a claw, and the claws are next to impossible to find. While this is not as convenient as slab reefing, it works well. Sail shape is quite good.

PostPosted: Mon Sep 06, 2010 11:51 am
by GreenLake
This clawless method sounds like it might be easier on the sail, too.

Instead of a line, somebody suggested in another post to use a strap. The friction generated by wrapping rises quickly with the number of turns and it may not be necessary to actually tie the line (or strap) to anything.

PostPosted: Tue Sep 07, 2010 10:20 am
by seandwyer
Hey Guys,

I'm a little confused on this. Are you suggesting that the main sheet be rolled around the boom along with the sail until you have reefed as much as you need then just continue to use the main sheet as you would from mid boom? The friction of the sail wrapped around along with the main sheet is enough to hold everything together?


Roller reefing

PostPosted: Tue Sep 07, 2010 10:28 am
by Helderberg Complainer
On the DSII, the main sheet is attached to the boom with a block and a shackle. To roller reef you remove the block and shackle. You tie a line (I use 1/4 inch Dacron line) to the bail that the main sheet block was attached to. When the main sail is rolled on the boom the new line is rolled up with it. When enough has been rolled, the boom is locked forward so it won't rotate. Then the main sheet block is tied to the new line. The main sheet block ends up right where it would have been if you had not reefed. Hope that's clear. Good luck.