Shroud locations and bowed masts

[c_witch]

Hiee all,

Ok so this is a new to us boat. We have never sailed it before nor seen it rigged for sailing. We have two sets of shrouds on her. One set the baby stays located just below the spreaders follow the mast down to the deck and then out to the outside of the cabin where the chain plate is. Note: these shrouds are inline to the mast or nearly so when looking from abeam. The mast head shrouds pass thru swept back spreaders and attach to chain plates about 20 something inches behind the chainplates for the baby stays. The mast has a bow in it that is impossible to get out with any type of adjustment to any of the standing rigging. The center of the bow appears to be at the attachment point of the baby stays. Ok today while sasha and I were looking at it, she gets on the deck and pulls back on the baby stays slightly and the mast comes straight. It seems to me as though for some unknown reason the PO moved the spreaders so they would sweep aft slightly and then moved the mast head shrouds aft and the baby stays forward where they attach to the chain plates. It appears as though most boats have the mast head shrouds attaching directly or nearly so opposite the mast on each side and the baby stays usually aft of this location. You can see the holes in the mast where we assume the spreaders were originally attached allowing them to basically come down opposite each side of the mast.

Any thoughts on this??? We have no information on rigging this boat and have not been able to fine any. Actually we are not even sure this is the original mast and boom.

On another note. Yesterday we did finally get out of the inlet and into the ocean. Although it did have its moments. The channel is not properly marked on the charts used in OpenCPN ie CM-93 NOR on the paper chart issued by CHS here in Canada (this is the latest chart btw). We put the jib up and sailed about for a time. In coming back in the wind picked up and the jib was not powerful enough so we hoisted the main also. A puff of wind hit the jib and turned us abeam to the wind (about 25 knots) just as the main halyard was cleated off. The main filled and and we heeled way over (read I though ready for a knock down) but I managed to grab the main sheet and let the wind spill out and we came up right again. I did give me a good scare though. We did tack back and forth working our way back in and upon reaching the second set of buoys marking the inlet entrance dropped the sails and motored back in as it was getting late 7:00 PM or so.

c_witch

A few pics of our first adventure under sail. I think we were about 2 nm out and it was really windier then what we should have been in as sas has never sailed and its been a very long time for me. Winds were 20 to 25 knots and onshore. Seas about half a meter or less.

 

[Victory]

First of all.... do you have a backstay?

Next... those aren't baby stays.... they're called Lowers. You could say Uppers and Lowers and people would know what you mean. On larger boats, with two or more spreaders there are intermediate stays... The uppers are also called "cap shrouds".... If you have two sets of lowers, like I do on my Cat 27, then they would be forward and aft lowers... Okay... enough on the terminology.

The reason I asked about the back stay is because if you don't have one (very common on smaller boats not to) the uppers must be swept back behind the mast to counteract the headstay.... in most cases the spreaders will also be swept back also. Think of a radio tower and the three sets of guy wires holding it up.

It sounds like you need to tune the rig with what you have..... so start by taking the tension off the lowers, then adjust the fore and aft postion of the mast by setting the headstay. Now you can use the uppers to adjust the side to side position of the mast... tightening on one side means easing off on the other.... once the mast is where you want it... adjust the lowers to get the mast completely straight....side to side.. that is...

You can prebend the mast (fore and aft bow, if you wil) by adjusting the uppers, they will interact with the static headstay to curve the mast. The lowers keep the mast from bowing sideways.

You can google "mast tuning" and find a ton of info on the subject.

 

[c_witch]

Picture worth a 1000 words

Ok so the teminology is off . Here is a picture please forgive the roughness I am not an artist. Unlike the picture the mast is not straight but has a bend in it to the bow and more or less centered at the spreader. In other words the mast forms an arc and the curve of the arc is centered more or less at the spreader and points to the bow. The leech of the main sail has some flutter which seems to be, being caused by the bow in the mast ie not straight. As mentioned in my first post if we switch the upper and lower shroud chainplate attachment points then we can staighten the mast with the lower shrouds.

c_witch

PS this boat had a jury rigged bowsprit when we bought it and also has a second jib? which we figured had to do with the PO having tried to set it up as a cutter rig.
The furler we have is a Barton and relies upon a s/s wire rope sewn into the leech of the sail. This is why we cannot reef with it.

My little drawing below:

 

[Merlin Clark]

Hi Brina,
First off, congrats on your first sail on this boat! Cool!
From your description and the drawing I'd loosen that 2nd (inner) forestay first and see what that does. Any idea why it was added?
Not to be too dramatic but since there is nothing (like running backstays) to counter a strain where that inner forestay connects to the mast, it could cause problems like trying to pull a bend in mast when you hit a gust.
I'd try to get the jib on the forestay and get rid of the inner unless there is a good reason for it being there.

 

[c_witch]

Hi Brina,
First off, congrats on your first sail on this boat! Cool!
From your description and the drawing I'd loosen that 2nd (inner) forestay first and see what that does. Any idea why it was added?
Not to be too dramatic but since there is nothing (like running backstays) to counter a strain where that inner forestay connects to the mast, it could cause problems like trying to pull a bend in mast when you hit a gust.
I'd try to get the jib on the forestay and get rid of the inner unless there is a good reason for it being there.

Hiee Merlin,

I should have mentioned that the inner forestay is already loose only tight enough to keep it from flapping in the breeze so to speak that is barely hand tightened. That aft stay is also loose enough that it has a hit of a sag from the mast head to the split stays or the transom. I will post another little drawing to try and indicate what the mast looks like. The only bend is fore to aft which is or seems to be impossibe to get out with any adjustment other then having virtually no tension on the backstay.

c_witch

 

[c_witch]

Here is a drawing showing the direction of the bend. It cannot be removed without taking ALL tension off of the aft stay and leaving it more or less without tension. As I mentioned earlier maybe the shrouds should be reversed and the spreaders relocated to what looks like their original position ie NOT swept back. Then the uppers would come down beside the mast on either side and the lowers would be aft of the mast. Any forward bow could be removed by tighening the lowers and if the bow went the other way then tightening the second forestay would again pull the mast forward and remove the backward bow.

c_witch

 

[Merlin Clark]

How about if you take slack the aft and take in the forestay?
Unless the mast is bent, adjusting the stays and shrouds will straighten it out.

 

[c_witch]

Hiee Merlin,

We decided to take the spreaders off to see if we could see where they may have been attached originally. We did find an outline of the original base and they were on the side of the mast perpendicular to the main sail mast track and NOT swept back. These are not the original bases either it looks as though they have been fabricated. Anyhow the mast is down and the spreader bases are here at home. We have to redrill for holes in the s/s rectangular base plate to match up with the original rivets used for the original ones. We'll then thru bolt them on and shim the bottom bolts to raise the spreader about 6 1/2 degree's upward at the tip to get equal angles between the upper portion of shround and lower portion relative to the spreader tip. Then they will attach to the chain plate opposite the mast and the lowers will attach aft of the mast. The uppers should not have any direct effect on the fore or aft stays tension that way and the lowers will now allow us to tension the lower forestay. We should also be able to easily prebend the mast if desired.

I don't know why the lower forestay has been added. Perhaps it had something to do with the PO trying to set the rig up as a cutter and going from a mast head rig to a fractional and then using the upper forestay to hank on a stay sail??

Calculating the angle between the spreader and and shroud was a bit of a PITA as I've not had to use that particular trig in sometime and couldn't remember the formula's.

I've also learned that I wish I could have used the larger MSD model with the 5 gallon holding tank, but we simply would not have had enough head room with that model as its 4 inches taller. So I guess somewhere down the road we'll have to add a small 5 or 10 gallon holding tank under the cockpit sole. After the first sail I'm also thinking it might be nice to have another 200 or 300 pounds of ballast added to the bottom edge of the swing keel box and running the full length of it. Perhaps a 1'' thick by 6'' wide piece of flat bar welded to the bottom edge of the box and top edge of the bar will do. I'll have to crunch some numbers on that to see about the weight. With the boat on the cradle you could feel the weight of the swing keel on the cable, but in the water I can grab the cable and actually pull the swing keel up, but by how much I have not measured.

That wind that hit us beam on with the main set up and sheeted in on the keel I figure knocked us over to about 35 degree's. This is something I don't wish to experience again. We were dead in the water at the time by the way. I was impressed with how fast she righted herself when I released the main sheet though.

I'm thinking that a maximum heel of 10 to 15 degree's and winds maximum of 20 knots to sail her with full sails. We do have one reefing point on the main so if we had to could handle winds a bit higher albeit not comfortably.

c_witch

 

[Douglast]

so i know you had some preset tensions on your rigging with the loo's guage...so what did you finally end up with for tension..??...

my upper and lower shrouds are chain plated side by side just slighty aft of the mast with slight swept back spreaders...

i sure can't see the need for your second forestay...spare if the one breaks ..lol..