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I guess my inexperience caught up with me this weekend and it's going to cost me on my '96 . I'm swallowing my pride and asking for advice so that hopefully I won't make the mistake again. Here is the situation:

Sailing cose hauled.
Wind: Forcast 10-15mph gust 20. Don't know what the actual was. I would say it was probably close to that.
Full main and genoa.
Heeling about 20 deg gusts would temporarily push over to 25-30 deg when I would ease the main to level out.
Speed 4-5 mph.

Now my obvious first thought is that I had too much sail. I always thought you reduce sail when the heel angle got too great. I figure 15 deg is the sweet spot for these boats. I'm on a lake so the winds aren't very erratic other than their direction. I figured if I was heeling too much more I would reef but I never got that far.

Does it sound like I was sailing beyond the boats capabilities? Or do you think there are other factors involved? The mast snapped clean at the spreader bolt. Could there have been a weak spot in the mast? shrouds too loose? Somethign else?

I guess mt pride is hoping it was something mechanically wrong with this old boat. I just bought it less than a month ago. Unfortunately, my gut is telling me I was just pushing it too hard. I guess I expected it to handle more than it did. Also figured it would heel over uncomfortably before damage occured.

What do you all think? I can provide more info if needed.

It does seem odd, I would expect that a correctly rigged boat should be able to be pushed right over "flat" until it "rounds up (automatically, regardless of what you do to stear it) and corrects itself.

In this case the "failure mode (method of correction of failure " was to snap the mast rather then round up and relieve preasue on teh mast. We don't know why it did this, it could be wrong rigging, it could be a weak mast. one this I have found on my mac- is that the shrouds like to "twist" themselves so that the eye is kinked in the chain plate, rather then pull straight the way it should.

For my own experience, can you explain the experience of this happen, what goes through your head, so that should it happen to me, or others, that we are a prepared as we can be when it happens?

The #1 thing I learned is that when the wife says it looks like the mast is bending too much you don't tell her the boat should be able to handle this much wind without trouble.

My thought was the same as yours. I figured the boat would be able to blow over sideways without dismasting. One thing that I think of now that could have had an impact is I still have the spreaders that can swing on the bolt. They aren't the rigid mounted spreader bars. I had just placed an order with BWY for the spreader upgrade to resolve that issue.

It's obvious that I had too much sail for what the boat in it's current condition and rigging would handle. But I thought it should be able to handle it. There could possibly have been unseen cracks around the spreader bolt hole. The rigging might have been too loose. I just don't know at this point.

It's sad because this was the first time we had her out in winds greater than "light and variable". We were having a blast actually sailing and getting somewhere.

I cannot imagine anything but a compromised mast..or improperly tuned rigging. That said....I have been in Winds in excess of 30 and with frequent gust in excess of 40 MPH and more, with waves crashing over the bow, almost to mast. Though I did have a single reef in place, I sailed under those conditions, for well over an hour.. I sailed the boat regularly after that, and never had a problem.. I had reason recently, to inspect my mast very very closely, and and my mast appears to be fine..
I also cannot imagine how on earth you could have a compromised that mast to the extent that it failed , yet the issue had gone unnoticed.. You say you sail on a lake . There by , I will assume your on fresh water. Boat lifts sit submerged IN fresh water 24/7 for months at a time, and I have never seen their aluminum structure compromised , let alone to the point of failure.. I am clueless as to why your mast failed..
If was I to " guess" I could only guess the rigging was way too slack .. Could your rigging have been that loose? Shock load exerted on an improperly tuned mast could easily exceed 10 times the normal load exerted on a properly tuned mast and rigging..
Brighter minds than mine, will have more accurate reasons and no doubt , solutions..

I like Divcoz's explanation the best. I often sail with the daggerboard almost out of the water and we are in a very gusty area wherethe wind forecast always seems to have gusts and double or more the average windspeed. Shockloading due to loose stays or an already compromised mast sounds like the culprit. You should be able to go way over and never worry about this happening.

I have certainly pushed our to about 40 degrees in a 30 knot wind with gusts above that, carrying a full load of sail (no reefs). With no ill effects (other than the Admiral giving her thoughts and opinions voiciferously). Having heard (and heeded) advice from more experienced users on this forum, I now try not to go beyond about 20 degrees and we put a reef in above 20 knts..

Since I just purchased the boat I can't say much for it's history. The only thing I know is that it has always been in fresh water. The previous owners kept it in the water for at least 3 years so who knows what kind of issues arise from that.

The rigging itself survived just fine. There was no other damage to the boat or rigging. I just disconnected it all, coiled it up, and zip tied them to the lifelines. Maybe it was age related or there was previous damage from the previous owner. The only other thing I noticed was a slight sideways bend in the mast when it was on the trailer. I appeared to be straight once it was stepped up.

It seems like most have pushed their boats a lot further than I did so there was likely other factors involved. I guess I'll just be shopping around for a new mast and go from there. Make sure everything is rigged correctly and try and stay around the 15 degree heel angle in the future.

tlgibson97 wrote:The mast snapped clean at the spreader bolt. Could there have been a weak spot in the mast? shrouds too loose?

Winds alone should not have done this. Something was wrong with your hardware.

I don't understand the "spreaders that can swing on the bolt" you describe. Nevertheless, the boat should have taken the winds just fine. I'm going with rigging too loose or a structural defect in the mast at the spreaders. You describe it "bending" which makes me think something was too loose.


--Russ

Can you post or send some high resolution pictures of the mast where it is broken, of both ends of the break?


Im sure it will show either corrosion failure or fatigue failure - you cant break the mast on these boats at the spreaders in 20 mph winds under normal conditions imho...

Could be as simple as someone using regular steel hardware on Al and corroding the mast at this location.

Ditto Steph on the photos.. can't tell much without seeing the damaged area. But on first guess I'd say it would have to have been compromised in some way, and perhaps loose stays compounded the problem.

Here is a photo that was taken shortly after it snapped. You can see the type of spreaders that are on it. I guess they were on pre 1996 X's and apparently were still on some '96's. They are just an F bracket holding the spreader bar with a bolt. The lower shrouds attach to the bottom part. But the bolt basically just acts as a hinge and the spreaders are held at whatever angle the shrouds hold them at. BWY has an upgrade kit that addsa bracket to make them rigid and non pivoting. Looking at the pic it looks like those spreaders is what saved my rigging. They just basically folded up and created slack in the upper shrouds when the mast snapped. I'll probably have to replace the spreader bars anyways because when I took them out one of them had the hole all elongated from years of rotating on the bolt.



Here it is after everything was tidied up.



I will take some close up photos of the ends of the breaks in the mast to see if there is any corrosion or any other signs of fatigue.

My 96X was built in April of 96 and had the swiveling spreaders you have/had. Macgregor sent free replacements to owners when the factory converted to the fixed type. The explanation I remember was that certain conditions could stress the mast and when sailing in some conditions problems could develop. 1.)Sounds like the PO of your boat didn't upgrade when or if it was offered. 2.) The boat may have been moored or stored in mast-up mode and subjected to sustained winds causing flexing and vibration in the spreader attachment area. 3.) I agree you rigging was too loose.

I think mast failure is more rare but I have had both spreaders become separated due to grooving and metal fatigue at the inboard ends and fall away from the sockets upon lowering the mast. (Macgregor replaced for free, thank you Steve K.). I upgraded my D model to the new spreader socket type as soon as I got it.

Closely inspect your old rigging when you replace the mast.

I have read of afew "X" masts breaking at the spreader bolt in recent months which makes me wonder why? My guess is metal fatigue at the spreader bolt hole due to the squeezing of the mast every time that bolt is tightened. I'm sure no-one uses a compression sleeve between the two spreader brackets and every time that bolt is tightened, it crushes the mast slightly. Noone could tighten that EXACTLY the same each and every time, and in fact probably tightens it alittle more each time and then it relaxes as the spreaders are removed. Repeat this process at Xtimes per year, times Xyears and you got fatigue. My question would be to those that have had this happen, do you take down/put up your mast frequently (as opposed to mast up storage) and do you take the spreaders off each time? How tight do you make that bolt? Any bolt going through a mast should have a compression sleeve going through the hole so that one can tightly hold the item to the mast without crushing it. Add in Catigales theory of metal corrosion at the hole and its now even weaker there.

I was not aware of the hinging spreaders before now. Seems a combination of that design and a loose upper shroud would be all it would take IMO. When mine snapped all it took was a little pressure on the outer stay at about spreader level, the spreader bent back (which it sounds like your spreader mount is designed to do) and that was it, a little twist and down she came. I was amazed at how little it took.

Trying to stay on the positive side replacement is not near as expensive as it would be on many other boats. Beach cats use similar masts and used their masts go for around $200.

Here is a link to a thread from when I replaced mine which lists a few different masts that could work:

http://www.macgregorsailors.com/forum/v ... .2#p221108

Interesting.. just exactly which sources have relayed this information? I was surly unaware of any issues..

THE CUSCUS wrote:I have read of afew "X" masts breaking at the spreader bolt in recent months which makes me wonder why? .