Shroud tension - MacGregor 25 (1983)

Mar 15, 2013
5
MacGregor 25 (1983) Casino NSW Australia
Hi All,
Any input re setting shroud tension for cap shrouds and lowers for a Mac 25 would be appreciated.
Lea
 

caguy

.
Sep 22, 2006
4,004
Catalina, Luger C-27, Adventure 30 Marina del Rey
Working with what you have can be a real PIITA. I've done it but it takes a lot of patience. The veneer adjusters are made so that you can make really small incremental changes. The tension is made with the front shroud turnbuckle and tightens the four side shrouds but the side shrouds need to be adjusted so that when the front shroud is properly tensioned the side shrouds are also tensioned and balanced accordingly.
Once you get them adjusted you do not need to disconnect or change them when trailering. You will however have to release the fore stay and adjust each time. The manual is vey vague and tells you to tighten enough so that the leeward shrouds to not sag when sailing.
Here are a few suggestions to make your life a whole lot easier.
A Loos Gauge Model A is very useful. It has the two wire sizes that you need.
Turnbuckles (4 of them) make adjusting the tension 100x easier.
A Johnson Lever for the front stay allows you to release the front stay with out loosening the front turnbuckle. If you get the Johnson lever you will only need 3 turnbuckle, as the lever replaces the front turnbuckle.

http://www.shopsoundboatworks.com/l...PyPD1PKhKcuhaoFdycBwerpV1o8zEzFlv4aAodH8P8HAQ

http://www.westmarine.com/c-sherman-johnson--quick-release-shroud-levers--P002_065_008_509

I only reference the above e links to show you what hey look like. You can find them on eBay for much less.
 
Mar 15, 2013
5
MacGregor 25 (1983) Casino NSW Australia
Shroud tension

Thanks for your response Frank - I will check out the lever idea.
Regards,
Lea
 
Apr 24, 2006
868
Aloha 32 Toronto, Lake Ontario
Ditto on the Johnson lever. It can replace the need for turnbuckles on your shrouds too. The lever will relax the rigging enough that adjusting the original "vernier plates" is a snap. It takes am about 15 minutes to adjust our rigging this way - I make several small changes and sight up the mast each time. Need to keep the mast straight via shroud tension.

Also, here is an excellent article, on how to properly tension a fractional rig:

http://www.alohaowners.com/index.ph...-rig&catid=22:miscellaneous-projects&Itemid=6

Chris
 
Mar 15, 2013
5
MacGregor 25 (1983) Casino NSW Australia
shroud tension info

Thanks Chris, I had a look at the article that you posted - it's very helpful!
Cheers,
Lea
 
May 16, 2011
540
Macgregor V-25 Charlton, MA- Trailer
Great article Chris. I am Leery about over tightening my V25 rig. Even the manual states that the lee shrouds should have some slack under heavy load. I have wanted to get a Johnson lever for some time. Maybe before the season is out. Like all Mac owners with a family money can be tight. I have the stock turnbuckle there now and use the jib halyard to aid in tightening the rig. Is being able to pin the forestay by hand under a heavy pull too loose? I did a full alignment and tightening this spring. I want the rig to be tight enough and still be safe.
 
May 16, 2011
540
Macgregor V-25 Charlton, MA- Trailer
I have noticed the sag in my forestay under heavy load in photos. I never knew the cause. Cool.

You can see my mast rake and tension in the first pic and the second shows the sag under load. Sorry to see the poor tension on the jib luff. Conditions were poor and re adjusting the sail was not in the cards at that point. 2-5 off Monomy, Cape Cod. My brave daughter was riding the bronco!
 

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Feb 20, 2011
7,833
Island Packet 35 Tucson, AZ/San Carlos, MX
I have noticed the sag in my forestay under heavy load in photos. I never knew the cause. Cool.

You can see my mast rake and tension in the first pic and the second shows the sag under load. Sorry to see the poor tension on the jib luff. Conditions were poor and re adjusting the sail was not in the cards at that point. 2-5 off Monomy, Cape Cod. My brave daughter was riding the bronco!
Can't really see mast "rake", but certainly mast "bend".

In some states, bowriding is considered illegal! :cussing:
 
May 16, 2011
540
Macgregor V-25 Charlton, MA- Trailer
Not illegal in MA or RI as far as I know. She had her legs around the station. No slip. I actually had her come back to the cockpit after a few dousings.

Bend? As far as I know rake is the amount of mast bent back to the stern. Not a nautical pro. Is rake the pre tensioned angle to the deck or what you see in the pic? I learn every day.
 
May 16, 2011
540
Macgregor V-25 Charlton, MA- Trailer
From what I can see the USCG states no one on the bow underway unless there are seats designed for that in place and no limbs over the side. That certainly can't apply to sailboats. I have seen more meat hanging off the rail even while not racing. Even while changing headsails underway. I don't know of to many people that can do that from the cockpit. My curiosity is enabled. I am going to do some checking.
 
Feb 20, 2011
7,833
Island Packet 35 Tucson, AZ/San Carlos, MX
Not illegal in MA or RI as far as I know. She had her legs around the station. No slip. I actually had her come back to the cockpit after a few dousings.
Just a rant. Please forgive me. ;)

Bend? As far as I know rake is the amount of mast bent back to the stern. Not a nautical pro. Is rake the pre tensioned angle to the deck or what you see in the pic? I learn every day.
Me, too.

Anyone, correct me if I'm wrong, but I've always defined mast rake as degrees/distance from vertical on a straight mast, and mast bend as curvature from straight.

"Cease not to learn until thou cease to live."
 
May 16, 2011
540
Macgregor V-25 Charlton, MA- Trailer
No sweat. That's what makes these forums great. I have learned so much here. Everyone can share experience/ es and the depth of information is awesome. I attached a couple pics of rake and bend.
 

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Sep 25, 2008
923
Macgregor & Island Packet VENTURE 25 & IP-38 NORTH EAST, MD
Ken, in your first picture, either your mast is bent like a banana (possibly from storing on the boat without a center support--my old mast was like that) or your backstay is way to tight. You want to be able to tighten the backstay and bend the mast like that whenthe wind is too much and one wants to flaten the middle of the sail. But to have it like that all the time isn't doing you any favors in light to moderate winds. The backstay should only be tight enough to keep it taught. Only on a masthead rig does it help keep the forestay in tension, on a fractional rig its purely for shaping the mast. The second picture says there is not enough halyard tension on the headsaill. Either the halyard is stretching (what kind of line are you using?? needs to be a low stretch type like Sta-set) or you're not making it taught enough. Thats why big boats have winches on the mast for the halyards, but are overkill on our boats. Do you just cleat the halyard off on the mast when you raise the foresail? I put a cam cleat on the mast so i can pull like crazy and not loose any tension when i wrap the cleat.
BTW, the leward shrouds will almost always go slack under any kind of wind. Our boats dont have any kind of bulheads in them to keep the two sides apart. If you wanted, you could tighten the shrouds up and make the boat less beamy.
 
Feb 20, 2011
7,833
Island Packet 35 Tucson, AZ/San Carlos, MX
Ken, in your first picture, either your mast is bent like a banana (possibly from storing on the boat without a center support--my old mast was like that) or your backstay is way to tight. -snip
I agree. Likely too tight a backstay.
 
Jan 10, 2011
291
Macgregor 25 Lake Lanier
BTW, the leward shrouds will almost always go slack under any kind of wind. Our boats dont have any kind of bulheads in them to keep the two sides apart. If you wanted, you could tighten the shrouds up and make the boat less beamy.
Good to know that the leeward shrouds get loose on other Macs. My shrouds get looser the longer it sits on the water. After it sits on the trailer for a while the shrouds are nice and tight(but still get loose to leeward under wind power). After it has been sitting in the water for a couple of months the shrouds appear to loosen up. They still look tight but after I start sailing I notice that they are not tight enough. Even looser than normal.

I have a hard time figuring out my shroud tension.
 

caguy

.
Sep 22, 2006
4,004
Catalina, Luger C-27, Adventure 30 Marina del Rey
Even when they are as tight as you think they could possibly be they are still not tight enough. Tensioning them with the Guage is nerve racking. I set them on the lowest reading on the Guage and they still felt too tight. I don't worry as much about the cable as I do the chain plates.
 
May 16, 2011
540
Macgregor V-25 Charlton, MA- Trailer
Cuscus- The mast is straight. I think the bend was due to running down wind in heavy wind. You can see the sail against the spreaders. Should the shrouds be tight enough to prevent this? The back stay seems to be loose enough just gets tight when running. The front sail was definitely loose. Just a sloppy set up. I clearly did not have it tight enough. I do need to replace my halyards. Original equipment. I set up my shroud tension at the beginning of the year. I did it on the trailer. 5' level on the boot stripe and across the seats to get it level. I used a floor jack to level the trailer. Interesting that it may change in the water. I never thought of that. I will check it again on the water this weekend. I am a true trailer sailor. She gets hauled after every trip. I certainly am not a pro at this stuff and appreciate the help.
 
May 16, 2011
540
Macgregor V-25 Charlton, MA- Trailer
I like the cam cleat idea. I do the once around the cleat and pull and pump technique. Like pulling the string on a bow then cleating it. I get the no bulkhead thing. The boat squeezes together. I am going to loosen my back stay this weekend.