Demystifying the Mainsail

[Don Guillette]

Here's another thing to think about. Next week I'll be planting my garden. I usually wait until 3/15 (last chance of frost) but the weathers been so great in Tucson that I'm going to take a chance. So, can spring be far behind for you guys back East and up North that haven't seen dirt since November?? Soon you'll be putting your boats in the water and you'll be needing a lot of boat stuff.

Remember who provides all these sailing forums for you FREE OF CHARGE!! It's SAILBOATOWNERS.COM. Give them your first shot for your marine purchases. What has BoatsUS or West Marine done for you lately or forever??

I don't care what mates suggest regarding other books on sail trim -- my introductory sail trim material will stand on it's own against any of them -- but what really GALLS me is when sailors use the sailboatowner.com web site to suggest other places to purchase stuff that Bly & Phil sell. I've never meet two people who are more customer service oriented that those 2 folks. I try to ship books & charts orders no later than the day after I received their PO -- that wasn't good enough for them and they drive me crazy trying to please their's and my customers!! I'm sure they subject their other vendors to the same pressure.

A couple of weeks ago I asked Phil if he could provide a total number of topics that have been presented on the SAIL TRIM FORUM and the total number of responses. It couldn't be done but the total combined number has to be in the thousands. Over the years, I've searched all kinds of sailing websites that discuss sail trim and none of them provide the "straight sail trim skinney" that this forum does. No where will you find the kind of sail trim knowledge Phil & Bly provide thanks to the likes of RichH, Joe from San Diego, Stu J , Scott and others. They provide the final word and all you you have to do is try it out on your boat.

Where were these guys and this type of a forum when I was trying to figure out how to trim sails on a silly sailboat?? God, it would have made my learning experience so much easier!!

Remember SHOP SAILBOATOWNERS.COM FIRST!!!

 

[Scotty C-M]

Don has a good point about supporting this website. While I do like to know about other sites and their good prices/services (even posting those on this site - free market, free internet), I am in need of a new gasket set for my Lewmar port lights. I can buy them here for about $20! I'm taking his advice and buying them from CatalinaOwners.com. I also plan to buy Don's Sail Trim Chart. But, back to the topic....

My biggest challenge right now in sail trim is that the "new" boat has a in-mast furler system. The main is pretty much roach-less, with no battens. I don't change the halyard tension much because I have it nicely tensioned for the furler. It looks like a good hoist tension because the sail, well, it just looks good. I've been adjusting the outhaul for draft, the vang for draft position (mostly off the wind), the main sheet for twist and the traveler for windward helm and healing (and twist). I pretty much do it in that order.

Perhaps, Don and the rest, you might do me the favor of advising me of how I can improve these thoughts. For example, perhaps I should be playing around more with the halyard tension?

 

[Sprega]

On the wind, traveler for angle of attack, sheet for twist....... Off the wind,sheet for AOA and vang for twist. I have no experience with in mast furling. I suspect the main is cut rather flat. So draft amount and position may be a challenge. Is there a Cunningham ?

 

[Scotty C-M]

Thanks, Sprega. You are correct, the sail is cut very flat. There is no cunningham. With a mast head rig, seems that most of my drive is comming off of the jib?

 

[Jackdaw]

Scotty,

First shape, then trim. As sprego notes, rig a Cunningham. It will allow you to adjust draft position after you set draft depth with the outhaul. You can mostly leave your halyard alone in this mode.

I'd suggest three basic 'shapes', with apparent wind speeds of 0-6. 7-15, and 15+. Get the sail shaped, then trim for the wind. Work on the shapes, then mark your control lines for repeat ability.

Traveler is your primary control. After that is used up range-wise, set your vang and use your mainsheet.

You are right, your negative roach main is smaller than normal, but you should be able to trim it effectively like a traditional main. Remember, your genoa has negerive roach!

One other thing. Remember apparent wind speed changes with direction. So correct shape for going upwind in 16 knots apparent is different than reaching in the same true breeze with 10 knots AP!

 

[Jackdaw]

Thanks, Sprega. You are correct, the sail is cut very flat. There is no cunningham. With a mast head rig, seems that most of my drive is comming off of the jib?

What is the size of your head sail? Many of the 400's came with 135s, but I see you are in the Santa Cruz/SanFran area, where big breeze can mean a jib as a primary headsail.

 

[25yearslater]

I will second or third Don's recommendation to use SBO for purchases. I used them at every opportunity during my restoration project and found the prices comparable or better than most any other vendor that I used. The shipping charges on all but the heaviest of items were better than the typical UPS/Fedex other vendors favored making SBO the lower cost vendor. The partnership with Doyle sailmakers allowed me the opportunity to purchase both the 140 and Asym last year as the price was less for the two when compared to one sail from other sources. I even saved a few bucks when my blower wheel exploded and Bly found me a suitable replacement saving hundreds on a full blower replacement. Now back to mainsail trim.

 

[Don Guillette]

Scotty C-M: On a masthead rig the engine is the jib. On a fractional rig the engine is the mainsail. With your set up you should probably go to full hoist and forget it. On my C30 I went to full hoist and backed off slightly and used a Cunningham to adjust draft position. My halyard was not led back to the cockpit so in the beginning I had to make adjustments at the mast and I'd end up with line all over the deck --the Cunningham was much easier for me to deal with.

A word about Santa Cruz-- that's one windy place to sail. I was there for the Catalina 30 Nationals one year and we raced in 30 to 45 knots of wind and with no reef. The Santa Cruz guys didn't reef so we didn't either. I wrote an article for the Catalina Mainsheet about the race. It was titled "who are those guys??". I got the title from the Butch & Sundance movie. We thought we had the race in the bag and a Santa Cruz sailor came out of nowhere and overtook us.

 

[Scotty C-M]

Thanks for the ideas, they are consistant with my own observations. Yes, Santa Cruz can be blustery (very much like San Francisco). My jib is a 135 (although I have not confirmed that by measurment). I find that it is perfect for up to 20 knots. At 25 it really wants to be furled a bit - and still keeps a nice shape. Above 30 everything gets rolled up proportionately. Also depends on angle of sail (apparent wind). I think it was Jackdaw who pointed that out. So if any of you're going through Santa Cruz, let me know and we'll go for a sail!

 

[Don Guillette]

Originally I had a 150 but it turned out to be too much sail for me to handle alone on a Catalina 30, so I sold it to a Catalina forum lister and bought a 135 high cut. On the first sail I didn't like it and sold it to another Catalina forum lister. At this point my wife is getting a little peed off at my antics. She never knew what I was actually paying for this stuff because the $$$ number I gave her was 1/2 of the true cost (she, like most wifes, knows I'm full of crap but lets me think I'm putting one over on her!!). Anyway, we (she) decided I had one more shot at it and it better be right -- I bought a 135 deck sweeper but had it cut so it just cleared the safety lines. Turned out to be the best sail I've ever used.

 

[Scotty C-M]

That's funny, Don. My wife triples all my cost estimates. Come back to Santa Cruz and we'll go for a sail!

 

[Don Guillette]

Scotty: Thank you and I'll take you up on the offer when we get back to your neck of the woods.

Your boat brought back memories to me. Years ago in So Ca, I kept my C30 at Shoreline Marina in Long Beach. A sailor who kept his boat in Los Alimitos contacted me regarding purchasing my book and chart. I told him I would be in Long Beach doing some work on my boat and I could drop the products to him at his boat on my way home. All I knew was his slip #. I had no idea what kind of a boat he owned -- until I pulled up to the "big boat" area in the marina. I knew I was in trouble as I'm in dirty sneakers, stained jeans and a stained T shirt but I was stuck. He greets me in blue pants and a white sweater over his shoulder and his wife looks very nautical and like a million bucks. It's a Catalina 40'!! On board I thought I could play basketball in the main salon!! It was the biggest boat I've ever been on. It all worked out -- I had the problem not them -- and we became great friends. I've delivered a lot of books and charts to boat owners in So Ca over the years but I always ask'ed them what kind of a boat do you own!!

If I get to Santa Cruz I'll be sure to dress properly for the occasion!!