cracked mast

cracked mast

Postby BillSmith » Thu Jul 13, 2017 3:18 pm

If a picture is worth a thousand words, am afraid these might be worth tens of thousands...

Have read the documents on this site by Eric Sponberg. A few other repair related articles online were helpful. My questions:

Could this be a mere 'cosmetic' outer layer crack? (Going aloft this weekend to shove a thin blade in portside crack to check depth.)
If it is just a hairline fracture from mast flex, can I throw some white duck tape on it to protect from UV and critters?
If I were to caulk and brush on some protective paint layer, assume I need something neutral or run risk of having disparate materials cause more damage?

Given there are no other visible cracks, fearful that this is structural. If so...

Anyone have experience in the SF Bay Area with carbon fiber mast repair? (Talked to SF Boatworks, will revisit them next week. Headed to Alameda and maybe Sausalito.)

Just got the boat up to speed with repaired instruments and the like. Can recommend Myles in Florida if you have B&G gear.
Attachments
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Starboard view
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Port view
resize 25 port view.jpg (92.8 KiB) Viewed 662 times
Bill & Carole Smith
Freedom 35 Pedrick
SweeTART
Coyote Point
San Mateo, CA
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Re: cracked mast

Postby Camino » Fri Jul 14, 2017 12:37 am

Bill - have you checked with Jock at KKMI Richmond?
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Re: cracked mast

Postby BillSmith » Fri Jul 14, 2017 10:27 am

Thanks, Tom for the reference. He will be my next consult.

Did the rounds over at Alameda. The disparate responses to seeing the above pictures is amazing. Everything from "You need a new mast" to "It's just a flesh wound" and carefully crafted caution from those that have no real experience with carbon fiber.

My current assessment is this crack is the outer layer of material. Probably no structural issues. If we can figure out how to haul my fat fanny up to poke around, I'll further the investigation and slap some silly putty or tape on the fissure as a temporary protectant against UV and whatever else (ozone?).

Don't know how easy it would be to ream and sand the crack, apply some filler and repaint. Not my skill set. Dropping the mast isn't a frugal fix.

Research suggests the mast might have been painted originally with Awlgrip white. There a few shades of white and this mast may have been repainted. Perhaps a racing stripe is in SweeTART's future?
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Freedom 35 Pedrick
SweeTART
Coyote Point
San Mateo, CA
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Re: cracked mast

Postby Goose13 » Fri Jul 14, 2017 10:59 am

Bill,

I Have the blue F33 KC up in Vallejo. I noticed similar cracks on both of my masts about half way up (it runs the circumference of the mast). My mast are colored black and it looks like that is where TPI joined the two halve together during the production. I've been up my mast a few time and I do not believe it is structural. I sailed my boat up from Oxnard the winter of 2015 and I was in winds up to 30knt with full sail and she was sailing fine. So I'm thinking mine are cosmetic and I don't loose any sleep and don't reef until the wind is over 30.

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Re: cracked mast

Postby gamayun » Tue Jul 18, 2017 12:17 am

My mast has something similar near the gooseneck. Appears to be cosmetic. When I had the mast down last year, I had repairs to the jib/spinnaker sheave done by Panda Love in Alameda. His thoughts were that these were cosmetic, too.

Carliane
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Re: cracked mast

Postby philipl » Tue Jul 18, 2017 11:24 am

I had similar lateral cracks on my F38 mast. I posted my concern on this website some years back and got an interesting response from the engineer (Rick) who worked on Freedom masts from 1980 tom 1985. I have copied his response below.

"I am the engineer that did the structural engineering on Freedom masts from 1980 - 85. I would not worry about the crack you are seeing. The laminate that creates the bulge below your crack is different from that which comprises the main body of the mast laminate. Most of the fiber in the mast runs straight up and down (some plus/minus 45 glass plies). The laminate in the collar runs 0/90 and is comprised of woven glass fiber. The dissimilar expansion and contraction of the glass and carbon fiber laminate will ultimately yield that type of crack. There is fairing material that forms the transition between the collar laminate and the mast laminate. Your crack is probably only in the fairing material which is rigid and homogeneous (not unlike polyester body filler). The constantly high torsional forces on the collar laminate as well as the expansion contraction are what caused the crack. You might explore the crack to see if it is in the fairing material. If it is, this can be carefully sanded out (dremel tool) and replaced with a white flexible caulk (white GE silicone) and should not return."
Philip Leahy
F-38 ex Manchester, MA.
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Re: cracked mast

Postby mike cunningham » Tue Jul 18, 2017 12:37 pm

gamayun wrote:My mast has something similar near the gooseneck. Appears to be cosmetic. When I had the mast down last year, I had repairs to the jib/spinnaker sheave done by Panda Love in Alameda. His thoughts were that these were cosmetic, too.

Carliane



Ditto on my Freedom 30, cracks around the collar where it tapers to the mast, been there for years in all kinds of heavy wind.

BTW I had some sharp bolt ends sticking out of the sail batten sockets along the luff of my main. These rubbed against the mast while sailing deep on the trip to Hawaii. Didn't realize it at the time but the bolt ends were gouging fairly large craters in the mast about two inches from the track on the port side of the mast. When I had the mast out to repair lights and other stuff after the race I inspected these gouges, cleaned them and epoxied them up. None had reached the carbon layup. Well, one of them was right at the carbon but did not penetrate. Point is the coating on top of the carbon layup is quite thick, maybe as much as 1/4 inch. I wouldn't be surprised to see a crack in the surface coating but it might be worthwhile to remove some material and see if the crack extends into the carbon. This is pretty easy to investigate. Someone mentioned a dremel, that would work but I would be mindful of not taking any carbon out by accident. Go slow.
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Re: cracked mast

Postby yarrow » Thu Aug 03, 2017 11:24 pm

not sure from pic if cracked through laminate or just filler on top with paint. best way is to sand down through paint and filler to see if when you get to carbon there is no crack, if there is a crack in laminate, a basic wrap of material will do with staggered layers to make up for amount removed to get to solid material.
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