Stay Adjuster Alignment

[c130king]

Fellow Mac'ers,

Went for the fourth sail on my boat today. Pretty windy on the St. John's River (at least for me and my bud). I only used the reefed main and no foresail. I think the winds were 15-20 knots on the river. Lot of white caps. But there is a sailing club about a mile south of NAS Jax and they had a race. About 10 boats (I would guess 20 to 35 footers) doing a 1 mile course (give or take) due North and South with NNE winds. It was pretty cool watching these guys race...tacking back and forth going upwind. Full mains and foresails heeled WAY over! Then some of them put up spinnakers for the downwind run. It was fun to watch. Maybe I will be there someday...not that brave yet .

Anyhow, back to the topic. I had planned to adjust my stay adjusters today when I raised the mast. My last sail I noticed that my lower shrouds seemed a little loose (especially on the Leeward side) and the foresail seemed a little saggy (to my very untrained eye). From reading other posts on this subject it seemed like others were tightening the lower shrouds to fix this problem.

So I raised the mast and then looked closely at my stay adjusters and planned to just tighten the lowers by about a 1/4" each. However, upon further inspection I discovered that my lower shrouds are not set in the same holes on both sides so I decided not to mess with them yet.

Here are pics of the starboard and port stay adjusters. You can see the lowers are not set in the same holes (hole 2 & 2 on the Starboard and 4 & 1 on the Port).


Starboard Stay Adjusters


Port Stay Adjusters


Is this standard? Does this means the shrouds themselves are not the same length? Could they have stretched or something so they had to be tightened to different settings?

I guess these could actually be really close...within less than a 1/4" inch or so for all I know.

I was hoping to just tighten them up 1/4" inch on each side and just live with that for now. Not sure if that is a good idea if they are not set to the same setting to begin with. I guess I will have to break down and by a tension gage to get them to the same tension.

Appreciate any thoughts on this situation.

Thanks,
Jim

[Moe]

It is certainly possible the shrouds are not the same length. What matters is that the total length, including the adjuster, is the same and that can also be evidenced by the straightness, or lack thereof, of the mast.

[c130king]

Would length or hole-setting matter if I used a tension gauge and got them to the same tension?

Jim

[Chip Hindes]

Would length or hole-setting matter if I used a tension gauge and got them to the same tension?

Yes, because is is possible to get the mast seriously out of alignment and still get correct tension on the shrouds.

You need to get the mast straight side to side, with the correct bend and rake, and the correct tension, all at the same time. It's really not as difficult as it sounds. I've only done ity twice in six years, but my procedure was to get it straight side to side, raked and bent properly first at low tension; then work on bringing up the tension.

[c130king]

I have seen at least two different types of Loos Tension Gauges. Is this a type that will work for the upper/lower shrouds?

I thought I had seen this before on this site but can't find it now.





Found this one on Ebay. Never bought anything from Ebay but might give it a try.

Thanks,
Jim

[Scott]

Yup, Agree with chip and this to add.

You can have the mast straigh and have the tensioners in different holes due to small differences in length from side to side.

Mine are not in the same holes and my mast is very straight.

http://macgregorsailors.com/phpBB/viewtopic.php?t=5225

This thread is my take on it.

[paj637]

C130king,
I'm in St Marys, GA. Been thinking about towing down to St Johns and going downstream to Green Cove Springs. I see you have only sailed four times in your M. I'm waiting to get mine registered to get in the water. Should get it in at St Marys next weekend. I know of a couple of other 26Ms in the area. Why are you at NASJAX? Reserve duty? Have you thought of going out of Mayport. Beautiful base and areas off shore are great.

[Moe]

That is one correct Loos gauge, in that it measures both 1/8" and 5/32" cable. They also make a "Pro" version that's not much more expensive.

My procedure is loosening the shrouds, disconnecting the backstay, getting the mast rake set with the forestay turnbuckle, getting the mast bend set with the upper shroud tension, while keeping the mast centered side to side, tightening the lower shrouds enough to lock in that bend while not introducing any side to side bend, then reconnecting and adjusting the backstay. You won't have that latter part on an M.

Besides eyeballing it, to see if the mast is straight side to side when adjusting the upper shrouds, you can hoist a metal tape measure (and a thin messenger line just in case the tape measure comes loose from the halyard) up to the top of the mast, then measure from there to the top of the chain plate on each side. The metal tape measure doesn't stretch like the halyard and is more accurate.

To check the bend, pull the halyard tight against the bottom of the mast in roughly the same place the block is at the top.

--
Moe

[c130king]

paj367,

First, congrats on the completion of your Navy career. I am on year 20 and counting in the USAF. And my Dad is a retired Navy LDO. In fact I was almost Navy but the USAF came through with an ROTC scholarship about 2 weeks faster than the Navy. I wanted to go subs...but now in hindsight I am much happier flying above the ocean than cruising underneath it

I live in Valdosta (stationed at Moody AFB) and my folks live in Jacksonville (less than 20 minutes to the Marina). So I bought my Mac from a guy just North of Tampa exactly 1 month ago today and trailered it up to Jax. I store it in the RV lot on the base. The Marina lot is full right now but I am on the waiting list. The Marina lot is right next to the ramp and it is not necessary to take down the mast each time. Jax is the most convienent place to store the boat and sail. The Marina suits my needs just fine and the river is plenty big enough (2.5 miles wide and at least 8 miles of length by the marina) to learn and practice on. Mayport is not nearly as convienent for me and I will wait a while on going open ocean. Us USAF guys get a little scared out there on that big ocean !

If you can get down to NAS Jax let me know. I would love to see a new Mac and share some sailing stories. Although I don't have that many yet .

Best of Luck,
Jim

[c130king]

Moe,

You said:

My procedure is loosening the shrouds, disconnecting the backstay, getting the mast rake set with the forestay turnbuckle, getting the mast bend set with the upper shroud tension, while keeping the mast centered side to side, tightening the lower shrouds enough to lock in that bend while not introducing any side to side bend, then reconnecting and adjusting the backstay. You won't have that latter part on an M.

Do you mean that the shrouds should be loose before raising the mast so they don't get tight and just using the forestay/furler to hold up the mast?

How much rake on an M? I thought I read on another thread that an M doesn't need rake.

I assume one needs one of those RAT's to tighten the shrouds while the mast is actually up. And you state to get the mast "bend" with upper shroud tension. What is the "bend" (which direction and how much)? I can't mentally picture how to do that without adjusting both sides simultaneously. Seems like the bend would be to one side and then you take the bend out when you tighten the other side.

Is there a recommended tension for this method. I have read different numbers from different folks.

Sorry if these are dumb questions (I know I hate dumb questions) but I have read a lot of threads on this topic I have to admit that I only understand maybe 50% of what you experienced riggers/tuners are talking about.

Thanks,
Jim

[Moe]

Do you mean that the shrouds should be loose before raising the mast so they don't get tight and just using the forestay/furler to hold up the mast?

To clarify, I didn't mean disconnected, but tight enough to keep the mast up side to side without bending the mast or opposing you turning the turnbuckle (which can gall the threads if too much).

How much rake on an M? I thought I read on another thread that an M doesn't need rake.

In that case, rake would be 0º and the mast would be plumb. If your boat sits level with its waterline stripe in the water, then you can adjust the trailer tongue so that the waterline stripe is level, and check if the mast leans back from level (has rake greater than 0º). Frank C has one of those cool digital readout levels. I'm jealous. I'll let one of the 26M owners tell you how much. As a generality, a boat often points better with a little rake.

I assume one needs one of those RAT's to tighten the shrouds while the mast is actually up.

There was a thread on this recently. Some have made other tools, some use awls, if I recall correctly.

And you state to get the mast "bend" with upper shroud tension. What is the "bend" (which direction and how much)?

When the upper shrouds are tightened, they push the swept back spreaders, and hence the mast, slightly forward at a point some distance below the points where the forestay and shrouds attach. This puts a slight bow or bend in the mast, along with the top of the mast moving slightly aft.

I can't mentally picture how to do that without adjusting both sides simultaneously. Seems like the bend would be to one side and then you take the bend out when you tighten the other side.

You do adjust both side simultaneously and the bend is fore/aft.

Is there a recommended tension for this method. I have read different numbers from different folks.

The appropriate tension is what's right for your boat in the winds you sail in. Too loose and the rig suffers shock loading. Too tight and the rig (and deck) suffer needless stress. I found 300-330 on the uppers right for our X, but the M is a different animal. Any "numbers" are just starting points. Some of the M owners have posted what works for them.

Sorry if these are dumb questions (I know I hate dumb questions) but I have read a lot of threads on this topic I have to admit that I only understand maybe 50% of what you experienced riggers/tuners are talking about.

I'm far from a Brion Toss or Don Guillette, but I've read their writings and figured out what worked for me on our 26X. Will be starting all over with the C-18.

--
Moe

[c130king]

Moe,

Thanks. That helps a lot. I am pretty sure my lowers (and probably my uppers) are too loose. I feel like there is shock load on the rigging when the boat rocks in the chop as I sail.

Can one "level" the boat on the trailer by holding a level along the water line and lowering or raising the trailer tongue until that line is level?

I will see if I can talk my Dad into attempting to help me with this over the Christmas break. At the very least listening to him make fun of me will make the event more enjoyable.

Jim

[Frank C]

I've done a lot of measuring on my 26X, but can't say how that might relate to your M. For mine though ... yes, my first stab at mast rake was by using the trailer's tongue jack to level the bootstripe, with that 24" digital level Moe mentioned. It reads to the tenth of a degree, showing from 90.0 to 00.0 degrees.

Coincidence! ... just noticed that Sears shows a similar device in one of this year's Christmas TV commercials. They're showing just a 12" model but you can also get a longer model (probably about $75)..

Before starting I had moved the trailer to an open section of our mast-up parking lot. My assigned stall is not level side-to-side, so I found a vacant area that would nearly level the axle, then unhitched the trailer ... etc. After leveling the bootstripe I checked level on deck, finding that the leveled bootstripe also left the sliding hatch level too - happy circumstance!

Now it was a simple matter to check plumb of the mast - my 26X was 86 degrees as delivered by the factory. You might reduce that by about one degree using just the turnbuckle (fully collapsing it), but my forestay was kinked so I needed to replace it anyhow. I took the old one to the rigging shop, asked them to make me one shorter by 4 inches. That change reduced my rake from the factory's 4 degrees aft ... to a new rake of exactly 2.0 degrees aft. I feel that 1.5 to 2.0 degrees aft is the best setting for a 26X in heavy winds. My change of 4 inches delivered 2 degrees, doing again I'd choose 5 inches shorter.

Be aware when shortening the forestay, you must verify that the new forestay will be long enough for your jib's luff length. My factory forestay had 9+ inches of excess stay length.

Regarding the process, I followed about the same procedure as Moe describes. Since the rig is already at some state of tune, just raise the mast and note the current shroud tensions in your log. I have the Loos Pro gauge pictured below.



Now you can sight the mast to be sure it is straight, then add upper tension to a target of 350 lbs. Leave the raising gear in place to release the forestay, shorten adjusters for both upper shrouds, reattach forestay, recheck tension. (If the starting tensions differ widely on port and starboard, I'd recommend adjusting only one shroud, target making them equal for starters.) Record all four readings each cycle since the tension on lowers can be altered by changes made to the uppers. My final settings are about 365# for the uppers and 325# on the lowers.

Finally, pictured below is a recent change where I added Sta-Masters to my rigging (total cost ~ $120). I feel they are a vastly better solution than even turnbuckles. They are very beefy stainless, indexed, make it MUCH easier to gauge your tension alterations - the picture speaks for itself. Read about it in this earlier thread, titled Mast Rake.




Note: Sta-Master was patented by a bright guy somewhere in the mid-west. I've spoken with him on the phone, but I have zero affiliation with him or his product, just appreciate the ingenuity. They are very popular among the racing dinghy classes and he advertises them in Sailing mag - where I came across them. I thought they'd be a great product for Heath's catalog, but my poll of our membership showed very little interest, so I just dropped it. Still - highly recommended for anyone serious about tuning the Mac's rig.

[c130king]

Fellow Mac'ers,

A few issues yesterday when I finally got around to tightening up the shrouds and forestay.

I tightened up the lower shrouds by about a 1/4" inch on each side. I tightened up the uppers by 1 hole (1/8" I think). The shrouds seem much tighter than before. So I got out my newly purchased Loos Tension Gauge and checked out the tension. Came up with 200# on the lowers and 220# on the uppers.

These numbers seem low compared to other numbers I have seen on this site...but I think those numbers were for the . Can anyone confirm what "good" numbers are for the ?

Also, I intended to tighten the turnbuckle inside the CDI Furler a "little bit". However, I still could not get to the turnbuckle. I pulled the Luff Support Pin and thought I would be able to slide the black Furler Drum up to get access to the turnbuckle. But I thought wrong.

Do I need to remove all the lines from the Furler first? Any help on this issue would also be appreciated.

I will take it out sailing today and check out how all my shrouds and the forestay look while under sail. I think it will look much better today...but then you know what happens when I start thinking .

Happy New Year.
Jim

[Catigale]

Jim

You can slide the furler drum up without disconnecting the sail on my setup, but depending on where your foresail is it might interfere and make you take the sail off to adjust this.

You should check the cotter pins on this turnbuckle at beginning of every season so that you make sure it isnt getting un-pinned...if it does, the mast falls on you....

Just to clarify terms

'Mast straight' refers to port/starboard straightness - if you look up at the mast you dont want to see any visible tip to either side.

'Mast rake' refers to fore and aft tip - in general the mast should be almost vertical with respect to fore aft, with some slight tip to the rear of a few degrees, which translates to a few inches of tip, if you will.

'Mast bend' refers to the curve the mast makes when tensioned the middle of the mast will bulge slightly forward when set 'correctly'

Again, my advice is to not take this too seriously for season one or two...spend your time handling your boat and having fun. The first 90% of sailing is learned in year one, the next 10% the rest of your life (Ghandi said that)

220# tension in those uppers sounds pretty loose. This is dangerous as it can let the mast pump in heavier air, which can break things. I bent a spreader first season due to Too-Loose (Latrec) rigging...

In summary

Make sure rig is tight enough. - especially uppers
Make sure that turnbuckle is staying put.
Sweat the details after you have some water under your feet.