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Adjusting Your Rig

131K views 121 replies 48 participants last post by  Samw90 
#1 · (Edited)
Adjusting Your Rig, step by step.

Small introductory disclaimer (because you Americans love to sue people):

For the record it is my strong personal opinion and belief that any and all work performed in a boat's rig should be performed and done by appropriate professionals, (that know what they are doing, because I have seen too many "rig professionals" that don't have a clue of what they are doing), do it yourself only if you have at least 3 ounces of brain and if have been around boats long enough and know with a minimal amount what you are doing..If you don't, PLEASE DON'T TOUCH IT, IT's NOT FOR YOU.

If you damage your rigging, your boat and/or hurt yourself or others don't come here blame me..get a life, I wrote this for intelligent people only.

This I write bellow is to help you get by should you not find a rigger near you. IT IS FOR INFORMATION ONLY.


Now the post:

A few months ago, one of our most dear friends here at Sailnet was stranded with a mast down problem, in a location where proper rigging professionals were scarce and the knowledge about rigging of the existing "rig professionals" was par to the local baker, veterinary and dentist…(I think he mentioned they were the same guy)…

So, and since he asked, I wrote him a small letter (sorry for the spelling mistakes and grammar), where I tried to explain to him how to set his rig in a way that would allow him to continue his journey and even get by in the future.

Please note this is my own experience, and other people may have better procedures..like I say, I am not a professional, and do this based on my own experiences. So if you don't like it, write you own and post here. It will only enrich the site. Please keep disagreements to PM level only, and I will discuss with you, should you not like or agree with me. Thank you.

HOW TO ADJUST AND SET YOUR RIGGING:

First you need understand this:

We will do 3 basic adjustment types:

Lateral Adjustment
• Longitudinal Adjustment
• Sailing (done later) Adjustmet


1) Lateral Adjustment.

(NOTE: this has to be done in a day with no wind with the boat perfectly horizontal, shift weight if you have to, to balance the boat).

a) Install the mast, and make sure the intermediate and lower shrouds are lose, but attached.

b) Make sure the stays and back stays are attached but not over tightened. At this point you want the mast as vertical as possible.

c) Remove the boom, or lower it so its not pulling on the mast, we will need the topping lift.

d) If the mast is keel stepped, remove the centering thru deck bushings at this stage.

e) Once the mast is up and vertical by eye observation, take the topping lift or the main halyard and measure the distance from the top of the mast to the boat's toe rail on port side. Repeat on starboard side, make sure the location of measure is symmetrical and at the same distance from the bow.
f) If the distances are not the same, tighten the side with the longest measurement.

g) Tighten the upper shrouds to a snug fit the same number of turns on each side, until the mast is perfectly centered.

2) Longitudinal Adjustment. (Rake)

(NOTE: this has to be done in a day with no wind with the boat perfectly horizontal, shift weight if you have to balance the boat).

Rake will help increase or decrease Weather helm. Aft Rake increases weather helm, improving pointing, forward rake does the opposite.

Normal rake is 1 to 2º degrees aft for cruiser boats and up to 4º deg aft for high performance racers.

a) Install a bucket with water under the boom by the mast.

b) Attach a heavy object to the main sail halyard and dip it the bucket but it should not touch the bottom of the bucket. (The bucket and water are used to dampen the swinging of the halyard.)

c) Measure P, which is the distance from the boom to the top of the mast.

d) Measure the distance from the halyard to the edge of the mast, at the gooseneck.

The distance should be as follows in the table:

Note, if you have a T shaped mast head, for halyard sheaves, add the distance of the T leg to mast to the above calculations.

Here is an example:

Our friend's mast is 42 feet long, or 12,8 meters, therefore for:

0,5º Deg rake = 11,52 cm = 4,33 Inches
1º Deg rake = 22,4 cm = 8,66 Inches
2º Deg rake = 44,8 cm = 17,3 Inches
3º Deg rake = 67,2 cm = 26,3 Inches

He also had a mizzen mast, and in his case, the mizzen mast has 21 feet, or 6,4 meters, therefore, for:

0,5º Deg rake = 5,76 cm = 1,96 Inches
1º Deg rake = 11,2 cm = 4,33 Inches
2º Deg rake = 22,4 cm = 8,66 Inches
3º Deg rake = 33,6 cm = 12,99Inches

e) Measure the distance from the halyard to the edge of the mast, at the gooseneck.

f) Adjust the rake as needed, using the above table, using the stays and triatic also, (should you have a triatic), don't forget that, ok?

g) Once all is where it should be, and the mast is where you want it, I would go with a rake of 1 º Deg for both masts for cruisers and 3% for racers.

h) Later on, once you sail, if you "feel" you need more rake use above numbers and adjust all again.

Note if you have a mizzen, for the triatic, you need a little help to get up there, but try to do it once with only one climb.

3)Dynamic Adjustment.

This will be obviously done later, if you feel you need more bend or better mast flexibility. See note further down, as at this stage we need to talk about tension in the rig.

The next step is therefore set the right shroud tension.

RIG TENSION​

1) Shroud tension

We now need to tension the upper shrouds, so let's tension them.
The values I calculated for our friend in the example are as follows:

a) All shrouds, including the upper, intermediate and lower are to be tensioned to 15% of the cable breaking load which in his case was:

3/16 cable the breaking load is 4850 lbs, so 15% of that is 727,5 Lbs

1/4 cable the breaking load is 7054 lbs, so 15% of that is 1058 Lbs

5/16 cable the breaking load is 12566 lbs, so 15% of that is 1885Lbs

b) The stays and triatic are to be set at 20 to 25% of the breaking load.

Use the same calculations above, to calculate the setting values, if you have a LOOS gauge, use it to set these tensions.

c) Now for the main shrouds, if you don't have a Loos, or are just a cheap person, you can use a measuring tape. I did for many years.

You will need to attach a tape of at least 2 meters to the shroud, so that the zero or the beginning of the tape starts at the turnbuckle.

The rule is simple each 1mm of stretch means 5% of the breaking load, and that is valid for ANY CABLE IN A SHROUD, no matter what the diameter is!!!

So you want to have at least 3mm of "growing" or 0.11 inches stretch when you're at the right tension, for 15% tension…cool huh??

Simple. Repeat the other side. Don't do all 3 mm in one go. Do 1mm on each side and measure and adjust slowly so you don't throw the mast off alignment.

Once the upper shrouds are tensioned, go to the next step.

2) Mast Pre bend

Once the masts are where you want them to be, and before we tension the shrouds, we need to set the masts curvature, or pre-bend.

For this attach the halyard that was in the bucket so it ends at the mast foot.

Now adjust the baby stay and or forestays so that the belly of the mast goes forward. Takes a few tries.
The max bend at rest should not exceed half of the mast diameter.

3) Max Mast bend (back stay and or triatic if you have one)

Tension the back stay on the mizzen first, (if you have one), so that the distance from the vertical halyard to the mast is half of the mast's diameter (IMPORTANT - DO NOT EXCEED)

The mast bend when the back stay is pulled should never ever be more than 2% of the height of the mast from the top to the deck (not cabin). In our friends case with a 42 foot mast, at full back stay pull the mast top should not move back more than 10 inches. OK?

NOW IN THE WATER!! Dynamic Adjustment continuation of chapter 3 above.

OK so where are you going to set the intermediate and lower shrouds??

LOWERS

Easy. At dock, adjust the lowers so they are just tensile to the finger, use the Loos to set them equally port and starbord, they should be almost flexible at rest. Hard but not too much. These can only be adjusted once you sailed to measurel.

INTEMEDIATES


also at dock, Should have a flex of about ½ inch when at rest.


The lower shrouds adjustment


Now, when you go sailing, on the first tack, see if the mast is vertical and doesn't bend sideways when you are on a tack.
Look from underneath and see if it's straight.

If the mast bends to leeward, kind of like bellies to the low side, the lowers are too flexed.

Go to the lee side lower, and turn it a few turns, and note how many times you turned.

Then tack to the other side and see if its good. If its still bent, go on the lee side one and do the same number of turns plus a few more, repeat tacking and adjusting till all is good and straight.

The Intermediate shrouds adjustment


It's the same as with the lowers, except now it's the top part of the mast that "bends" to leeward if they are lose.

Those only adjust at the marina, ok??? You need to go up there.

So a recap:


1) Tighten by hand the upper shrouds till the mast is straight.
2) Adjust mast rake with stays and backstay/triatic.
3) Tension upper shrouds to 15% breaking load
4) Adjust mast pre-bend
5) Adjust back stay movement to not more than 2% mast lenght
6) Adjust lower shrouds while sailing
7) Adjust intermediates observing while sailing and adjusting at dock

Have fun.
 
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1
#34 ·
xuaraax,

The # sign can mean a few things

# ie lbs in this case lbs of force before it breaks,

or

I use it at work for "square unit"......unit typically being a foot of measure, meter, yards etc could also be used as the unit of measure.

My first option, ie lbs of breaking strength, could in some instances, be kilograms or equal force measure too, but lbs is most common.

Marty
 
#35 ·
I went through this process recently and may be able to save someone some trouble.
The elongation method is a pain get the Loos gauge from the start.
This process requires patients. don't try to set the mast in column and lock it down at the dock. It wont work. The only way to get it right is to get the mast centered in the boat with the right rake and prebend and then do the rest undersail.
to do this right you can count on it taking forever. To get no wind and no wave action to get the mast in column at the dock is hard. then doing the real tuning under sail in the wind speed you want to tune for may require several outings and a lot of tacking.
Don't kid yourself that you can put the mast in collum and lock it down at the dock. the real tuning part can only be done under sail, with a load on the mast and stays. There is no short cut here!
I tuned my rig for twenty knots I figured that was good middle ground for us.
And did not exceed 15% on the lowers 20% on the caps.
I maybe the exception, Our boat was layed up for a long time when we bought it and I don't believe the rig was kept in tune pryer to that so i had a hard time getting things adjusted. I tried moving the mast with the stays at first and finally just loosened everything and started from scratch. And followed a procedure much like the the one Giu. posted.
Then after all the headache. and some help from Alex I finally got it right. I can drive with my finger tips on the wheel, my weather helm went down and the boat points higher and is faster.
A couple things that I found out were that ambient temperature has a big effect on tension and I have a hatch just aft of the mast. It was a lot easier to sight up the mast from the salon looking up through the hatch than trying to to do it at the base of the mast.
When the rig is right it makes sail trim and helm balance so much easier.
I look at it like this. if the foundation is crooked the house is crooked. There is no way you can get proper sail shape with the rig being out of wack.
If the center of the mast is falling off to leward then you cant flatten your main in heavier air. just when you want to depower the sail it's gettig powered up. The same as running loose back stays will add power to a jib.
It was an enjoyable process for me the results were well worth the effort.

Hope this helps
 
#43 ·
I tuned my rig for twenty knots I figured that was good middle ground for us.
And did not exceed 15% on the lowers 20% on the caps.
How does one go about optimizing the rig for 20Knots?

The rig I would like to set is a twin spreader aft swept 7/8 rig with a set of lowers and intermediates. The mast is a keel stepped affair. The mast is held firmly at deck level but the base can be moved fore-aft.

Currently the boat is getting quickly overpowered in high winds, constantly broaching into the wind in the gusts. It looks like pulling hard on the backstay and cummingham has little effect in flattening the middle part of the sail.

My other problem is that I do not own the boat so, of course, before playing about with other people's stuff one must be extra careful on what one is doing.

From the excellent info found in this thread I conclude that, for this rig setup,
the rake will be determined by the forestay length while the prebent will then be primarily determined my moving the mast base fore-aft keeping the shrouds fairly tight. The uppers should then be set to the 15% loading mentioned earlier.

It would seem then, that to optimise the rig for 20knots, say, one has to play about with the lowers and the intermediates.

Currently reducing the tension on the lowers results in some significant bending of the rig forward when pulling the backstay but the bent is nowhere near the 2% of mast length originally mentioned by Alex. Also the leeward shroud now becomes fairly floppy when sailing at 20knots so I am not sure if we have created another problem with the mast bending to leeward.

By the way, getting a rigger with a loos guage did not help much as apparently all he did was set the tension in the upper shrouds in port and more importantly the broaching problems remained.

regards
 
#36 ·
I bought a PT2 Loos gauge the other day. I have 7/32 wire on everything but the mid upper shrouds. which I believe is either 5/32 or 1/8. This is not listed as to what I need to check with current gauge. Does any one know how to figure out what the smaller wire number should be with the bigger gauge. As I really do not want to go buy a 2nd gauge for the smaller shroud.

Guessing by how the three sizes go, I should be able to halve the numbers for the 3/16 which is the smallest size for the gauge I have and work pretty close for the next size down. any one care to say I am correct, not quite right.........

I may in the end, email loos and see if they have it figured out.

Marty
 
#38 ·
LOL,

Actually got the same size, but the pro model vs your one level down. It was tempting to get the battery operated one tho!

You got crew for wed night racing yet? If not, we will be out, and I am sure with 15'ish boats out normally for summer racing, someone will want a hand.

Marty
 
#41 ·
Knothead, thanks for the good post, it enriches everyone's expereinces here to have guys like you around, thanks.

I don't have time to make one, but do you know where one can find the shroud breaking loads tables according to thickness, that shows both metric and imperial?

It would be good to add it here, if someone cares to do it. Thanks

Alex
 
#42 ·
Alex, most of the catalogs that list Stainless wire used to have the breaking strengths listed for the various types. I seem to remember they sometimes listed safe working loads too. I'll look around and see if I can't find something.

Then I'll try to figure out how to scan it and then attach it. I'm not really adept at that stuff though. :rolleyes::)
 
#44 ·
I think we need to know what type of boat you are sailing to determine if the problems you describe can be associated with the rig or not. Some issues with broaching or helm balance are more associated with the sailplan or a particular hull design and without knowing these things I can't say whether or not it is due to improper adjustment of your rig.
 
#45 ·
The boat is an Elan 37. The sails are Tape Drive racing sails.

Asking around on the WEB indicates that this boat does pretty well on the racing circuits even in high winds.

By the way I am not not necessarily saying that the rig is set up incorrectly. Merely that it is another paramater to check.

regards
 
#47 ·
Seems to me that your boat is similar in design to the J-105; in rated area and size, etc. I can't say for sure about the sailing properties because it appears that Elans are primarily sold/sailed in Europe. The listings on Yachtworld only show them available in Europe/UK. That's why I hesitate to say exactly what the problem is.

If I were betting; I'd say that the problem is due to the high SA/D ratio and that the boat is getting overpowered earlier than a heavier boat or a boat with less sail area. The J-105 fleet racers say that they are a beast in heavy wind and they are always cranking the backstay up and spilling the traveler down to keep the boat on it's feet; of course they are pushing it to the limits when racing in their fleet. These tactics also require a crew who is constantly trimming and "rail meat" to help stabilize the boat.

Again; I'd try reefing it down good and then see how the boat performs. You'd be amazed that when you reduce sail area; your leeway reduces, the boat stands up and is able to sail at a more optimal angle of heel and can actually go faster. Your pointing might be a bit reduced depending on sail shape but hey if the boat goes faster and is easier to control you are going to make your destination more quickly and with less struggle.
 
#48 · (Edited)
Xuraax,

I remeber writting something to you about your boat not long ago SEE HERE (I even was criticized a few posts after, when I know the boat, and know what it can do, from being on them, not from reading in magazines or bla bla bla)...

I had told you once that somethings are just the way they are, and must be changed to act differentely.

What happens is your boat may be dressed like a race boat, smell like a race boat, be among racer boats, even looks like one, and sometimes go fast as one, BUT it is not a race boat.

It's a fast normal production boat that can be sailed faster than normal and faster than the others..(but it's limited to a wind envelope)...

It still behaves like a cruiser, even if you add rake, tension, etc. It's a cruiser...designed as a cruiser, has a cruiser keel, and rudder, and hull shape...

You need to modify the keel, modify the rudder, lighten the boat, and make the boat go thru a racing oriented modification for it to handle the winds in Malta..specially when you start getting above 18kts.

There is little you can do without modifying it... you need to have a fast main traveller system, longer and thiner keel, a longer rudder, a different mast, different genoa controls, etc..

Some things are just like they are...your boat was made to sail faster than the other same type boats, but it has many many limitations...

A Ford Focus will never be a Porsche, even if you put stickers and go fast stripes on the doors..

Now, change the suspensions, brakes, engine etc...It will do as a Porsche, go fast as one..BUT it will never be one...

You need to start investing heavily (I know believe me) to make the boat do what you want..THAT boat will not behave good in strong winds, its a low to moderate wind boat...that boat is just a regular fast cruiser, like a Dehler or a Grans Surprise, it will never be a Sinergia or a B&C...

And to be honest...investing in that boat to bring it to do what you want..might as well buy an old IMS off the Copa del Rey in Spain, and then you'll be driving the Porsche...
Sorry
 
#50 ·
Thanks one and all for the many replies.

However this thread is not about whether this boat is a good racer or not. That may well be the final conclusion when all things are checked and confirmed to be correctly set.

The thread is about adjusting the rig, and recently it had shifted into how to optimise the rig for higher winds. That is surely an interesting argument.

regards
 
#51 ·
Great post, Giu!

Precisely I have a problem with the rigging and I was looking for an expert to help me fix it.

Only one suggestion, I am not acquainted with the cable measurements (1/4, 3/16, 5,16). Do you have at reach the equivalence in mm for you neighbours? (Well, I am not exactly your neighbour because I'm Catalan so we have Spain in between.... :D )

Thanks a lot!
 
#52 ·
Actually the tables I have are in millimiters. But for the guys here at sailnet I had to covert from KN and Kg to Inches and Pounds.

Here is a tble I made in Excel and took a snap shot, that should make it clear for everyone in Inches and Millimiters, KN, Kg and Lbs.

 
#53 ·
Nicely done. :)
 
#55 ·
In order to check the lateral position of the mast use the main (or jib for fractional rig) halyard and swing it to the port and starboard rails.

Don't forget to sight up the mast to look for bends. The lower shrouds can be used to straighten some of the bends. Often times the lowers are set looser to allow for mast bend. In fact in some racing classes the lowers are adjusted according to the wind speed.
 
#56 ·
Newby questions. How do you tension the shrouds on a three stay rig where the mast comes down after each use? How do you bend the mast with a three stay rig and no aft stay? The thin metal strip shrouds have to be disconnected to adust them. You place the mast thru the deck, connect the shrouds, connect the fore stay, pin the foot, and then you final tension the shrouds using the fore stay turnbuckle on my boat. There are upper turnbuckles on the upper ends of the flat metal strip shrouds. I could make balancing adjustments to balance the tension side to side with a ladder and the oak tree in the yard the way it is set up. Should the turn buckles be at the deck and the end that has to be taken loose to adjust be attached to the strap on the mast? Do you reverse them to get the adjustment made and then put them back as they were?
How much fore stay tension do you use when you have a mast that uses the deck as a pivot point?
How much rake is correct on a comet class boat with a shorter mast? It came adjusted for a foreward rake.
Does sail type change the answers? I have old canvas sails.

Sorry for all the questions, but I am trying to learn as much as I can before I do something really dumb from not knowing the correct procedures.
 
#57 ·
Giu,
There is something wrong with your statement that 1mm of stretch = 5% of breaking load. This has to be 1mm of stretch per 1 meter of length, or some other ratio. I used to build a system that used a 1/4" cable 800 feet long. Proper tension on that system was to stretch the cable 8 FEET!
 
#58 ·
Maybe it was the way I wrote it.

c) Now for the main shrouds, if you don't have a Loos, or are just a cheap person, you can use a measuring tape. I did for many years.

You will need to attach a tape of at least 2 meters to the shroud, so that the zero or the beginning of the tape starts at the turnbuckle.

The rule is simple each 1mm of stretch means 5% of the breaking load, and that is valid for ANY CABLE IN A SHROUD, no matter what the diameter is!!!
 
#60 ·
Keel, I am not going to argue this anymore.

You surely have heard about Selden masts, right?

Please allow me to redirect you to their shroud adusting manual.

PAge 30

PAge 31

PAge 39

I am sure your calculations are all correct and such..I got this this morning off the net by googling tension shrouds, and found this manual.

There are several more with the same instructions.
 
#64 ·
Keel, I am not going to argue this anymore.
Was not trying to argue anything Giu; I was simply trying to add some information to your excellent post of how to adjust your rig tension.

Since there was confusion on what your post was saying I tried to determine why it would be 1mm extension for 1 meter or 2 meters; but it is off by ~50%. The calculation is correct; so it must be a problem with the published breaking strengths. So I was doing some more research on 316 stainless and it turns out that the published breaking strengths must not be actual ultimate breaking loads; they seem to have a safety factor of 2 built in. The 15% breaking strength calculations I did earlier were based on the published breaking loads; while the Selden formula is based on the true Utimate Tensile Strength of stainless wire (actual failure strength).
 
#61 ·
I was rather pleased to find out that my motorsailer's 6 x 9 inch "tree stump" mast was in fact a Selden, so I purchased a Selden pole lift ring to fit in the handy grooves. Now, of course, I have to tap in holes for cheek blocks (or cut rectangular holes for sheeve boxes) to move the thing up and down.

I have a further question out of these Selden pages, though, Alex: See here?



Everyone I know tightens the turnbuckle with a screwdriver. Why a wrench/spanner?
 
#62 ·
Everyone I know tightens the turnbuckle with a screwdriver. Why a wrench/spanner?
I'll keep it simple...

That type of turnbuckles are designed to support tension forces only, and has very little torsion strenght, mainly because there are very little lateral efforts they need to support.....it's made that way when the turnbuckle is made, when the metalurgists make sure the grain of metal is more oblong, making it tension resistant, harder, but less resistant to lateral forces.

In using a screw driver, you are stressing the legs of the turnbuckle with lateral forces, (for which the piece was not designed for), and even twisting the turnbuckle legs, wich then get stressed, and the integrety of the intergranular structure gets compromised, possible causing it to fail at a later stage.

For this reason, the turnbuckle manufacturers make 2 flat surfaces, like a nut, to use a wrench, that will in turn provide rotational forces without stressing the legs of the turnbuckle.

Hope it was simple.

Alex
 
#67 ·
All good info but really...it's not that difficult to do.
Lay on your back, feet facing the bow, looking up the mast to see the straightness of it port to stbd. Adjust until straight with moderate tension on the shrouds or stays. Next lay on your back with your feet off the beam while looking up the side of the mast to check for bend for and aft. Adjust acordingly until straight with moderate tension on shrouds and stays...done. I've been doing it for 15 years this way.
 
#70 · (Edited)
Anyone,

I have NavTec rod rigging on my 40' boat. Should the lower shrouds have the same level of tension at rest as wire shrouds or should there be more tension? I noticed this summer that the lee shrouds were flopping around when we were sailing.

Hank Tully
Usually, the uppers are tightest, next the intermediates and then the lowers. This can vary with the type of rig. A good rule of thumb is that the larger the diameter, the more tension.
Your lee shrouds, in my opinion, should not be flopping around.
 
#71 ·
I used the folding method as Selden explained to tension my rig last year since the 1x19 wires were larger diameter than the standard tension gage available. It was easy to do and the boat now points better. Good explaination.

Another thing I did which may or may not be right is to replace the old spartite around the mast. It's keel steped and I was getting some leakage through the deck and when I went to replace the mast boot I saw that the original spartite(not sure if it wa spartite) was cracked and crumbling. I dug it all out and then just used the best silicone caulk that I could find to fill the gap. The silicon may not be as hard as the epoxy based spartite, but it does limit movement of the mast at the deck. Not sure if there is much movement anyway since the mast is thick walled. At the Annapolos boat show I asked the spartite people about this, but they really didn't have any good response. The one problem that I see is that the cure time for a thick ribbon of silicon to comletely cure might be excessive?? days..weeks ...months
 
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