There's a banana in my mast

[John, CD28]

Ok, I finally get around to the rig on my old boat. This is a 30 year old Cape Dory 28, masthead sloop with single spreaders. I buy a Loos PT-2, and Ivar Dedekam's book and have at it. It didn't take long to realize there's a banana in the mast, big one too. The mast was bending forward above the spreaders; the headstay's too short.

The four lowers (3/16") look fine - each has 500lb tension. The lower section of the mast looks straight and plumb.

A prior owner put the Harken roller furling on. The turnbuckle in the roller drum is as far open as it can be; no more length in there. I put a couple forged toggles under the roller drum and gained about 3". I tightened the backstay (1/4") to about 1,600lbs (per Dedekam) and she looks much better, but she's not there yet.

I take both ends of the mainsail halyard, pull each end down and tight along the front and back of the mast; I see I've still got a 1" gap on the front at the spreaders. The halyard on the aft side of the mast lays tight to the mast - there is still some forward bend.

The turnbuckle on the backstay is nearing its limit with about an inch to go top & bottom section - can't take up too much more.

Is it ok to just put a third toggle under the roller drum, or is there something better than "toggle chain" for lengthening a headstay? And what about the backstay? Can I put shorter threaded rod in the turnbuckle so I can take up another inch or two to keep the proper tension?

Any ideas? Or, is it time for a new headstay and a new backstay? Both appear to be in very good condition.

John

[Figment]

Something ain't stirring the kool-aid. With a masthead rig the length of forestay and backstay should affect rake, but not induce bend. How's the rake?

Bend has more to do with the lowers. Can you ease the aft lowers?

Is it KINKED at the spreaders, or is this merely the easiest landmark for the point of greatest depth of a nice even bend?

Is the CD30 keel-stepped or deck-stepped? I can't recall. I assume the spar was straight before it was stepped, yes?

[jollyboat]

[quote - Is it ok to just put a third toggle under the roller drum, or is there something better than "toggle chain" for lengthening a headstay? And what about the backstay?]

Yes you can put another toggle under the drum. You can also buy or frabricate plate links and get rid of the toggle chain if it bothers you. I would not tighten the back stay any more - nor would I leave the tension at 1500lbs that is great for windward work but not needed for off wind work.

Also keep in mind that your rig may have been set up with forward rake to help with weather helm. I would also consider an adjustable back stay tensioner - I have one on my Triton and very happy with it. 12:1 purchase is nice - can pretty much make my mast dance the tango if I want it to. If you are deck stepped don't forget to put in a removable compression post if you decide to install a backstay tensioner.

[/quote]

[John, CD28]

Something ain't stirring the kool-aid. With a masthead rig the length of forestay and backstay should affect rake, but not induce bend. How's the rake?...Bend has more to do with the lowers. Can you ease the aft lowers?

Before I added the two toggles under the roller drum, If I slacked off the aft lowers the mast would be straight, and leaning about 1° FORWARD (fwd rake). The top of the mast was about 5" too far forward. The two toggles I put in brought the top of the mast way back, but not enough to make the mast perfectly straight with the lowers tightened. I think the lowers have the right idea.

Is it KINKED at the spreaders, or is this merely the easiest landmark for the point of greatest depth of a nice even bend?

The aft lowers are causing the mast to take a bow shape as they try to pull the mast back plumb. All the lowers have 500lbs of tension on them. The mast itself isn't damaged, dinged, or bent. It looks like the headstay just isn't letting the top of the mast go back enough. It's a smooth curve, not a sharp bend or hook.

Is the CD30 keel-stepped or deck-stepped? I can't recall. I assume the spar was straight before it was stepped, yes?

This is a CD28, but both the CD28 and CD30 are deck stepped. And yeah, the mast itself is nice & straight. If I slack off all the lowers, she'll straighten right up (and lean forward). I'd like the mast to be straight. And between plumb and maybe 1° AFT rake at most; just slight aft rake. This leaning and bending forward stuff is not what I had in mind.

Any and all help much appreciated.
John

[Tim]

First off, stop using arbitrary numbers from a gauge or instruction book, and instead tune the mast by eye and feel, both in a static condition and under sail. Numbers don't mean a thing here. Every boat is different (even season to season), and there's no single "right" setting for your boat or any other. I note that you've had this boat sailing for several years prior to this; has this condition existed all along, or have you changed something about how you have set the mast up this time?

I feel that using gauges tends to lead one to overtension the shrouds on their cruising boat. They only need to be as tight as they need to be to hold the mast in column and to hold it in the proper shape and position, and this is usually less than one thinks; what this shape and position actually are will also vary widely from boat to boat and according to many intangible factors that one can't name, but can't ignore. Tension gauges may have limited use in one-design racing and the like, but in my opinion have no purpose on a cruising boat rig and only lead to awkward setups and overtensioned rigs that do more harm than good.

Even if your headstay is too short, which is certainly possible or even likely here, you can tune the mast to be straight and in column if you do it without any preconceived ideas about what your various tensions should be. You can add additional toggles as needed to effectively lengthen your headstay, put more tension on the forward lowers, and more tension on the backstay. Some combination of these applications ought to help you correct this bend, as long as you're willing to do it on the fly without regard for some random numbers published somewhere.

There aren't many (any?) absolutes in the sailing world, much as some would like there to be. The seat of your pants is almost always a better guide. Learn what tweaking a shroud here or there does to the shape and support of the spar, rather than trying to slot things neatly into a preconceived notion that, ultimately, will not get you to where you need to be anyway.

[Ceasar Choppy]

Amen to what Tim says.

Last time I used a Loos gauge, I turned my boat into the banana because the rigging was too tight. Obvious sign was not being able to close the head door.

Set everything up be sight, go sailing to make adjustments. Certainly the forestay will be the hardest part of this, but you can use the toggles to get it how you want, and then you'll know how long to make the tang that will replace them.

Good Luck!

[John, CD28]

As Yoda said, "USE THE FORCE, LUKE."

That's how I set the rig the first few years; I had been using the "twang" method for the 4 summers I've had the boat in the water, and just went to the Loos gage this summer. The rig tension isn't that much different in the end, but I do like having the gage. Maybe the tension numbers aren't perfectly accurate, but the gage itself is consistent, and it allows me to set and monitor relative tensions. And yeah, the banana's been there as long as I've owned the boat. It's only after reading and learning more about rigging this summer that it really started to bother me. Ivar Dedekam's book is a gem, and really enlightened me on the subject of rigging. The online stuff at Selden Mast is also helpful.

Yes, it's this particular set of tension numbers that keep this masthead centered over this boat and the rig standing properly. They are not target numbers, rather convenient numbers near the middle of recommended ranges. The tension feels about right for the boat, and is only a bit more than I would have twanged them to. Going to windward in 12kts, the leward cap shroud and leward lowers are no longer under much tension, but they aren't quite floppy either. The mast is still straight port/starboard too; it's not falling off to leward.

This boat appears to suffer no ill effect from these tension levels. The doors to the head and V berth still work fine. The supporting bulkheads show no sign of movement whatsoever. Nothing in the structure seems to be sagging, stretching, or compressing, as the tension is still the same weeks after I set the tension. The 1,600 lbs on the backstay feels about right too - the headstay keeps the luff of the genoa nice and straight now, and with most of the forward bend gone, the leach of the mainsail is no longer too tight and the foil shape is much better. The boat definitely goes to windward much, much, better now.

With most of the bend out, and rig nice & tight, the improvement in the boat's performance is nothing short of amazing. I think if I can just get the mast back into column, and hold these tension levels, she'll sail as Carl Alberg intended her to. Anything else would be a disservice to Carl's masterful work.

After reading the responses, I did find and order a single 5" stay extender from Defender, a cleaner solution than my "toggle chain" under the roller drum. This really ought to do it. I'll put the extender in and take up as much as I can on the backstay turnbuckle, and leave it at that. If I can't get good tension on the backstay with the extender in place, I'll put new stays on next season.

[Tim Mertinooke]

As Yoda said, "USE THE FORCE, LUKE."

[/Geek] Sorry John, but that was Obi-Wan in Episode IV when Luke was in the X-wing trying to blow up the original Death Star.... [/Geek]

[John, CD28]

I think you're right - it was Obi Wan.

I wonder if they had these rig tuning troubles on the X wings ;)

Apologies to George Lucas!

[Figment]

If you ease the aft lowers, does the bend go away?

[John, CD28]

If you ease the aft lowers, does the bend go away?

Sure does; nice & straight, with lots of forward rake.

[LazyGuy]

John,

If I am reading history right, you have been sailing the boat for 4 years with a considerable forward rake on the mast. You are now trying to get an extra 5" on the forestay and take 5" out of the backstay to make the mast plumb. That is going to change your helm considerably. Right now, I am working on moving the top of my mast forward to get rid of some weather helm. Yesterday we sailed from Point Judith to Watch Hill passage starting in 10Kts of easterly (actually ESE) getting up to about 25 and then back down to about 18-20 as we came through the passage. My arms grew about three inches along the coast of RI. That is why today will be spent moving the mast forward and cleaning up the boat after a week of cruising.

[Peter]

John,
It sounds like the person who made the forestay for the furler may not have "measured twice, cut once".

I got a Loos gauge for my birthday last year, one of the better ones (the gauge, that is). I find it very useful to get equal tension on opposite sides of the boat. When I bought the boat the rigging appeared too tight, and when I re-stepped the mast I had it too loos, so the gauge has been helpful to establish "bench mark" settings from which to experiment further.



I record all my settings and occasionally check them in the hope that if a stay was starting to stretch from failure or pull out of a fitting it would show up on the gauge reading.

It's also interesting to see the stresses a backstay tensioner puts on the different stays.

Ivar's book: what more can I say .... he certainly follows the "one picture is worth a thousand words" philosophy!

[Figment]

Yesterday we sailed from Point Judith to Watch Hill passage starting in 10Kts of easterly (actually ESE) getting up to about 25 and then back down to about 18-20 as we came through the passage. My arms grew about three inches along the coast of RI.

Reef? Twist?

;)

[LazyGuy]

Reef would have helped but it is bad on a good day.

[The Good Goose]

John
I Agree with Lazy Guy. My triton had alot of weather helm until I raked the mast forward. I f you have neutral helm with the mast forward I think you will find more weather helm with it aft. 5" does seem excessive for the forward rake but some forward rake may be desirable. I do not believe that the mast needs to be perfectly vertical for the lowers to keep it straight. Before you try any major backstay changes sail it for awhile and make sure the helm is ok.

Brock

[Figment]

Bad on a good day.... yeah I hear you. A PO shortened my boom, presumably to soften the helm, and I still chose to move (not rake, but MOVE) the mast forward a bit a few years ago.

I may have gone too far. In light air I actually have a bit of lee helm that I could try to rake-out if I cared to. Otherwise nicely balanced, though.

[Zach]

Hey Figment,

Did moving the mast forward mess around with your spreader angles at all?

I've been pondering the effect of chain plate placement (Which I guess has the same net effect as moving the mast...) and haven't found a whole lot out there. Getting the feeling its an eyeball it and go type art... grin!

Signed,
Zach...

(The guy thats been pondering putting the mast beam and supports on the forward end of the bulkhead... Weather helm sucks when ya have a torn rotator cuff!)

[The Good Goose]

Zach
I also moved my mast forward and I have not noticed any affect on the spreaders I moved it an inch or inch and a half. My guess is that there is this much play in the spreaders.

Brock

[Figment]

If there's enough play to rake the masthead back and forth 6" or so (there is), there is enough play to accommodate moving the mast step a few inches. Like Brock, I think I only went 1-1/2" or so, I didn't go completely nuts with it. I added a steel plate behind the mast beam (which is now mostly cosmetic as a result) and furred it forward somehow as well so that the step load still transfers to the bulkheads.

Thread drift is a beautiful thing. Why on earth are you planning to monkey with the chainplate locations? I can't imagine any detrimental effects, they're in different places on different tritons straight from the factory after all, but why?

[Zach]

Moving the chain plates to the outside of the hull on account of no bulkhead left between the tabbing on the starboard side (don't want to have that leak again!) and big feet. Have to stagger the plates one side or the other of the bulkhead to give clearance for the backing plate and bolts.

Been figuring to move them to the forward side of the bulkhead on account of the weather helm and moving the mast forward. (On a tabernacle too...)

Really though, I just spend to much time thinking about this boat, and how all the systems relate.

[Tim]

I just spend to much time thinking about this boat

It's a slippery slope. One thing you find after a while is that it's just all too easy to overthink everything.

Don't.

[John, CD28]

It's a slippery slope. One thing you find after a while is that it's just all too easy to overthink everything.

Tim's right (again).

On my boat I overthink everything. Invariably, when the job's done, I realize there was something I didn't think of.

I happily cruised coast of Maine two summers in a row with my old banana mast leading the way. Sometimes it's best to leave well enough alone, and just go sailing.



Cheers,
John

[bcooke]

Moving the chain plates to the outside of the hull on account of no bulkhead left between the tabbing

Per the original construction, a couple of holes on my chainplates missed the main bulkhead altogether. The bulkhead doesn't reach to the hull and the holes only went through the tabbing. I thought about panicking and then thought that they have been that way for 40 years with no signs of ill effects. Instead, I filled the space with thickened epoxy, and redrilled the chainplate bolt holes. It may not be great but it is better than it has been for its 40 year history.

As for thinking too much, that was a lesson I learned too. It is way too easy to start wondering how all the parts are going to fit and suddenly have spent two hours just sitting and looking around. It is actually quicker to occasionally tear out something you put in by mistake than to think out the whole process ad nauseum. Try not to think too far ahead. It only hurts you in the long run.

[Figment]

Instead, I filled the space with thickened epoxy,
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Way to go, chucklehead. Just made yourself a nice little hard spot that'll never ever fair-out.
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(kidding, kidding, come down off the ledge now, it's all going to be ok...)

[bcooke]

hehe, well I didn't actually put enough in to completely fill the gap. I actually considered hardspots at the time.

I should add that I was a mere babe in the woods when I did this. My first summer with the boat before I sailed it.

[jollyboat]

Thread Drift? This is more like a RipTide, quick somebody throw me a life ring! -

"I'v got a monkey in the mast chasing a banana and thinkened epoxy behind my chain plates and Zach is in bilge with his thinking cap on. . . . strum, strum, Chorus: Oooo aaah Loos Guage, Oooo aaah Loos Guage . . . strum, strum ...