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Catalina/Capri 25/250 Sailor's Forums

Catalina 250 Specific Forum

Tuned Rigging

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welshoff
Captain

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USA
253 Posts

Initially Posted - 08/08/2005 : 13:26:22

I finally took the time to tune the rigging last week (wed). All shrouds were loose on the leeward side while sailing (closed haul). When I loosened all shrouds in port to start tuning, I found the mast raked at 12"! I reset the rake to 4-5"; realined mast athwart ship; then set prebend to about 1.5". Setting the prebend gave me a good tension on the uppers (I think I gave them another turn or two for good measure). Didn't have a loos guage so went by feel. Set the lowers to center mast and to feel on tension.

Took it for a test sail Friday night (I had to do this to test the rigging before the wife would go out on the boat for the weekend - she was just a little nervous about my rigging abilities). I found uppers were set perfect (based on closed haul test sail - tension on leeward side - not loose or tight - tesion felt just right); lowers were loose . Came back to port; met the wife and daughter; stayed on the boat at the marina Friday. I readjusted lowers Sat morning and then headed out for an overnighter with wife and daughter (went to Jarrel's Cove). We had a blast - as you can see by the smile on my daugher.

What a difference a properly tuned rig makes! If you guys haven't taken the time to set up your rig; it is very worth your time. No more loose leeward shrouds, boat points closer to the wind, reduced weather helm, and improved ability to balance boat with sails. Best three hours of maintenance I spent on the boat this year??

Wil Elshoff
"Arcturus"
2004 - C250 WK #732

Edited by - welshoff on 08/08/2005 13:31:53

JohnMD
Navigator

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USA
207 Posts

Response Posted - 08/08/2005 : 14:32:56

I acquired a 95 WB so I'm also getting ready to set the wires. I've done lots of this on Hobies, but, they have chainplates so you just move things a certain number of 'holes'. My manual is real iffy, so, there's not much help there.

Do you loosen all the shrouds and set the forestay and rearstay first?

How do you determine 4 to 5 inch rake? Do you use a float and get the hull level first? If you just use gravity, it seems that the rake would be different almost every time you take the boat out.

Does it matter if you set the upper or lower shrouds first?

How do you determine that the mast is straight up and down (port to starboard speaking)?

Do you set the wire tension while sailing or before you put the sails up?

Thanks for any help you can give.

Edited by - on

welshoff
Captain

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USA
253 Posts

Response Posted - 08/08/2005 : 15:59:19

I basically did the following (from manual posetd on this web site - gives you some diagrams as well). Boat was sitting in it's slip in the water - loaded typically to how I sail with it. Rake would probably change depending on weight place on bow or stern:

1) Removed the jib/genoa.
2) Removed boom and mainsail.
3) Loosened upper and lower shrouds.
4) Hung a weight on the main haylard and noted mast rake (distance of weighted halyard from base of the mast). In my situation I had to pull mast foward. Loosen backstay and tighten forstay (I have a profurl furler and had to dissasemble partially to access turn buckle - I was able to pull forward enough to get 4"-5" of rake; any more and I would need to be shortening forestay)
5) With forestay set - put tension on backstay - estimated tension by feel (estimate amount of force to deflect cable a couple inches)
6) Double checked rake - still 4"-5".
7) Adjusted uppers to center mast athwart ship - used main halyard and went from Port to Starbord chain plates. I also double checked with tape measure from chainplate to swag fitting on cable.
8) Set about 1.5" of prebend in mast. Tighten port and starbord uppers equally. Check prebend by pulling main halyard to base of mast. Prebend occurs about halfway up mast. Again tension was set by estimated amount of force to deflect cable a 1"-2" inches.
9) Adjust lowers - tighten equally. I set slightly looser than uppers.
10) Took test sail and observed mast and shrouds when closed hauled - leeward side. Check for tension on leeward side. My uppers were good - lowers needed adjusting further. Also site up mast to asure it is "plumb" during test sail. Note: when my lowers were too loose you could see the middle of the mast go from port to starboard when tacking (not good) - plus they were loose on the leeward side. I took them up another couple of turns to finish the adjustment (equal turns on port/starboard).

I don't know how close I came with my tesion as compared to a Loos guage? I think by feel of the tension gave me what is needed?

Both uppers and lowers now are not loose or tight ont he leeward side close hauled. I also saw no sag in the forstay with jib set (backstay tension). I may still play around with the backstay tension?

Don't know if this is how every does it or not? My version.

Edited by - on

Bubba
Admiral

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USA
542 Posts

Response Posted - 08/08/2005 : 16:09:24

John, here are two sets of instructions I collected from this forum in the past. Click these links to download. They might get you started.

http://mywebpages.comcast.net/davendeb/misc/Tuning1.pdf
http://mywebpages.comcast.net/davendeb/misc/Tuning2.pdf

A quick answer to you rake question: Put your boat on her lines. Move some weight around if it's not sitting level. Hang a weight on the main halyard and cleat it off so the weight is just off the deck. The horizontal distance from the weight to the mast will be your rake. You can use the same halyard to center the mast port & starboard by running it to any point near the rail, cleat it off and then run it to the same point on the other side. It's a rough measurement, but effective.

Edited by - on

JohnMD
Navigator

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USA
207 Posts

Response Posted - 08/08/2005 : 16:43:49

Thanks a bunch. I'll let you know what I find. I'm pretty sure I need to add a bunch of sand under the Vberth. Kinda feels odd, adding some weight to a boat to make it perform better..........

Edited by - on

Arlyn Stewart
Master Marine Consultant

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USA
2980 Posts

Response Posted - 08/09/2005 : 07:16:40

William has it right, the 250 needs a fairly tightly tuned rig to avoid getting overpowered in a breese. Here are a few additional rig tuning thoughts.

Unfortunately, the modified B&R rig doesn't allow on the fly tuning so the power setting of the rig has to be preset and basically lived with. For the most part, this will mean that it should be set up for low power and a tight rig accomplishes that with a trade off of poorer performance in light air.

On the fly tuning is normally done by a backstay tensioner, which removes the pockets of both the heads'l and mains'l, but on the 250 only does so to the headsail while actually increasing the pocket and power of the mains'l hence a tensioner is "almost" counterproductive.

I say almost because the use of a tensioner will not provide depowering equivelant to a tight rig set up. It will provide a compromise of allowing a good loose rig for light air and moderate depowering for a breese.

From my experience, the heeling angles of a loose rig are reduced by a backstay tensioner by about 5 degrees. Keep in mind, that only the headsail is being depowered. From this, I'd guess that there is likely double that difference between a loose rig and a firm rig on a boat with no tensioner as William's experience suggest as both sails are being depowered.

There is a way on the 250 to gain full on the fly tuning of the power of both sails and it is very effective allowing great light air performance and the ability to harden the rig well for a breese. Unfortunately however, it requires the use of a running baby stay which adds a step to tacking as the stay has to be released to tack the jib across. While this may initially sound a bit too far out, it is very effective for the cruiser who is not tacking every few minutes and the releasing of the stay is not as difficult as one might first think.

The running baby stay essentially takes the place of the missing forward lowers that are found on most traditional rigs and is set between the mast at the spreaders and the stem head and serves to pull and hold the center of the mast forward to counter the loss of force of the spreaders if a backstay tensioner is set. This stay is low stretch line and is run through a block at the stem and back to a sheet winch for deploying.

When cast loose of the winch, it is auto retracted out of the way of the tacking jib by a bungee, which runs down from the spreaders to a turning block at the base of the mast and attached to the stay, thus it is a cockpit control using the lazy winch.

A byproduct of this running baby stay is some redundancy if the forestay should fail, as there is no other redundancy to hold the mast erect when equipped with a CDI furler, an emotional plus for the cruiser a long way from home.

Such a settup is probably only worth consideration by the racer or cruiser. It is almost imperative for a racer to accomplish on the fly rig tuning and the inconvenience of the added step to tacking is no big deal for a cruiser. I doubt a daysailor would benefit enough to make rigging power tuning capabilities worthwhile.

Edited by - Arlyn Stewart on 08/09/2005 07:22:02

Tom Potter
Master Marine Consultant

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USA
1913 Posts

Response Posted - 08/09/2005 : 18:17:47

I've been trying to find out why I have the wrinkles in my main sail for months, and now I believe I know why. I've come to the conclusion that its related to tune of the mast. (reverse bend)
I've been playing with the tuning on my boat for a few months now on and off trying to get the wrinkles out and the mast tuned property. I bought a Loos off E-Bay and set the rig using the the instructions included with it, still not right.
After reading all the data here, I'm going keep the loos in the box and start from scratch using the info posted here.
Check out the wrinkles in the picture below. I hate wrinkles

Edited by - on

Arlyn Stewart
Master Marine Consultant

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USA
2980 Posts

Response Posted - 08/09/2005 : 20:40:06

Tom, great picture showing your concern. I've at times employed a cunningham and in fact the fastest I've had my boat going, had the cunningham hardened to pull out the wringles and reduce sail draft to a minimum.

Cunninghams are not generally thought to be quite as effective or perhaps necessary on a full batten main with the idea that what can be accomplished with the cunningham can usually be done by luff tensioning with the halyard.

Try and firm up the luff with the halyard first. It may take cleaning the mast slot to reduce drag. I use the technique of cleating the halyard, then grasping the halyard at arm height and pulling it outboard of the mast to leverage the luff tight and while holding down pressure, snug up the halyard on the cleat.

If that doesn't work, then add a cunningham.

Edited by - on

Tom Potter
Master Marine Consultant

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USA
1913 Posts

Response Posted - 08/13/2005 : 17:10:18

Well I just spent a few hours tuning the rig (again). This time I left the Loos in the box until I was done, and only used it to see how close I came using the 2 finger method.
I loosened the back stay and both the uppers and lowers, checked the Rake and it was still at about 4 inches. So I set the uppers using the two fingers with about 2 inches deflection. (Prebend? not happening, must be a Tall Rig thing) Then set the lowers keeping them much looser than the uppers. I then pulled out the Loos and took my readings. I have 3/16 shrouds so the loos calls for about 500 pounds I was very very close, the loos reads about 23 on the scale.
The lowers are quite looser and the loos reads about 13. I tightened the back stay until the slack was out. I raised the main and the wrinkles are gone!

Still need to do my sea trials checks, I think the lowers are going to be to loose, but I should be able to make adjustments and watch the main at the same time so that the wrinkles don't reappear while tightening. I hate wrinkles

Edited by - Tom Potter on 08/13/2005 17:12:05

atgep
Master Marine Consultant

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1009 Posts

Response Posted - 08/13/2005 : 18:12:25

Hey Tom,
Once you get her where you like, use the gauge to record the settings. Then it will be repeatable. I use the "old school" method of tightening "just enough" and then make sure the mast is straight while sailing. I have the luxury of having double lowers.

Don't worry to much about the gauge conversions or the wire size. Once you get your cheat sheet of measurements it will be easy.

Tom.

Edited by - on

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