A crack at the top

[capta]

Did a visual inspection aloft today and thanks to digital innovation, got numerous pictures.
Going through the pics, I found a crack at the masthead, on the headstay fitting that wasn't noticed aloft. Thank you Pentax.
If you notice in the second pic, the other side is not attached in any way. The whole unit is installed in the mast, seemingly held in place by the sheave bolts. This weld does not seem structural or even be necessary, unless it's to hold the top on?
It looks very old and seems to be nothing of immediate concern, but I would appreciate feedback from you all out there.

 

[Gunni]

Are you fishing for a good reason to ignore it? :neutral: How has your luck been recently?

That sheave bolt that you are relying upon is in some very corroded and eaten up coated aluminum. It just looks like a spar that is past due for unstepping, and repair. Those painted sticks are a maintenance hassle, and the missing paint seems to accelerate the corrosion. I think you are seeing evidence that your masthead has been compromised. Doesn't mean your headsail is coming down any time soon, but you might want to have plan b for when it does.

 

[Lake Superior Sailor]

It doesn't look like anything to worry about to me. I would keep an eye on it and see what it does, may very likely been that way from the factory,Paint covers a lot. Looks like you are ready to repaint soon...Dale

 

[Brian D]

I know nothing about aluminum, but can't you weld where the crack is to reinforce the metal there?

 

[Sanman]

Dude, That looks pretty dodgy to me. I'd get that fixed.


You know what they say" Boat= break out another thousand...Yacht =Y'add a couple hundred thousand"

 

[Jackdaw]

That's TROUBLE.

On a masthead rig, the mast-top fitting is designed to spread the compressive loads of the fore and backstay over the entire mast top. So, stay loads attach to that fitting, and the fitting presses down on the mast column. That weld is what is holding your forestay to your mast.

 

[Don12364]

Do you think there might be another matching crack on the other cheek as well?
Your photographs don't show whether there is or not.
Perhaps you have others that show all is okay.
Either way I wouldn't put any load on that rig until the present defect is re-welded.

 

[higgs]

I would take the photos into a rigger and get his opinion.

 

[dscribner]

I was going to say NBD but now that I see the size of your boat, I'd suggest you drop the mast for a paint job and to weld that masthead. The loads imposed on a 60' mast are significantly greater than a 28' mast like mine. And if you have a fractional rig, loads can get even dicier. Don't put her ear in the water any time soon and get that looked at. The aluminum can be welded but be sure to get somebody with credentials. Unlike steel, welding aluminum weakens the material and deciphering the alloy used and the proper welding rod required should not be left to amateurs. Probably one of the reasons that they used what looks like 3/8 or 1/2" plate. Also, note the lack of penetration. I think the top plate is oversized in thickness in order to balance welding to the tension plates. Not an uncommon practice. But is does help take some of the load out of the bottom of the slot od the mounting hardware.

Don

 

[WayneH]

Just my biased opinion.

This and $5 will get you a Starbucks coffee-like substance.

If this was a load bearing weld, it would have been welded on both sides of the plate and across the front. The plate on the left side shows that the outside edges were only tack welded together to keep the top plate stationary on the mast. I adjusted the brightness and contrast on your "Crack 1" picture to better look into the recess area. Using your finger for width, you've got a 2 inch long tack weld there holding the top plate to the mast on the outside only.

"Crack 3" clearly shows the end of the tack weld and no progression across the end. If the top plate is such an issue, where is the weld continuation on the right side of "Crack 1"?

Having spouted all this "non-sense", something cracked your plate loose. You need to look inside "Crack 3" and down a bit to see if you have a crack just inside of this shot against the mast. THAT would be a problem.

Just one man's opinion and worth every cent you paid for it.

 

[DAVA390]

Re: Just my biased opinion.

would not the load bearing weld be along the mast,
vertically where we can`t see?

 

[Bill Roosa]

Since the shrouds and stays attach to it they tend to pull it down onto the mast. so this weld is keeping it from moving laterally. Now if there is some sort of shoulder on the bottom side of the mast head to make it fit to the mast proper then there is almost no chance this weld is anything more than a construction weld. If all this is true then the weld just keeps the mast head from falling off during raising and lowering the mast.
Course if there is no shoulder then the weld is VERY important. This is similar to the way a tabernacle works, no welds just shoulders and the shrouds hold it in place.
I'm thinking a trip to rigright to see an exploded view of the mast head might tell the tale