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Mast Step Repair

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Jeff Roy
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Username: Jeffr

Post Number: 106
Registered: 03-2001

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Posted on Thursday, November 17, 2005 - 07:40 pm:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

I found the rest of the pictures. I have tons of them, every step of the project.

Here are a few good ones taken just before I started the rebuild.
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jeffcantrememberhispassword
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Posted on Thursday, November 17, 2005 - 07:05 pm:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

I have more pictures somewhere, but this is the only one I could find on this computer. In this photo the only thing left is the main stringer that runs athwartships under the mast step.

There is one more keel bolt hiding uner there! I eventually ripped that out too and rebuilt it all.

If I find more pictures I'll post those later.
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Walter Kawula
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Post Number: 9
Registered: 12-2003

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Posted on Thursday, November 17, 2005 - 03:43 pm:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

Jeff,
Thanks for all of the photos of your repair job. Do you have any photos of the hull after you removed the old step and before you installed the new one?
Walter
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Walter Kawula
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Posted on Thursday, November 17, 2005 - 03:41 pm:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

Jeff,
Thanks for all of the photos of your repair job. Do you have any photos of the hull after you removed the old step and before you installed the new one?
Walter
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Jeff Roy
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Username: Jeffr

Post Number: 104
Registered: 03-2001

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Posted on Wednesday, September 07, 2005 - 10:17 am:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

So far the repair has held up very well. I have not seen any signs of anything moving of deforming. There has been no more weeping at the hull keel joint either.
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John
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Posted on Friday, July 22, 2005 - 07:55 pm:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

Jeff....The extensive description and photos of your mast step repair were excellent and a great service to the 9.1 fleet. I will need to rebuild mine this fall (2005). How has the repair held up after four years? Would you do anything differently? In the top photo, why did you insert that G-10 cover. It would appear that the mast plate would be equally well supported by the fore and aft members of the mast step without it.
Thanks,
John Brady, #50
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Jeff Roy (Jeffr)

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Posted on Thursday, June 14, 2001 - 02:06 pm:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

Lets try these photo's again. Unfortunately, they are out of context.

g10

plate

done
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Jeff Roy (Jeffr)

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Posted on Thursday, June 14, 2001 - 02:01 pm:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

Final Report:

Well my boat is going in the water tomorrow. Yesterday I had to go crazy getting everything ready at the last minute.

The yard was going to put the mast up this morning, so for good or bad I am finished with this repair.

Sure there were many other ways to go about it, but I think this all turned out pretty well and is much stronger and better designed than the original step.

g10
Here is the mast step just before I put the plate down. Unfortunately I did not leave enough width for the plate that takes the tenision load from the tie rod. I had to do some last minute butchery with a chisel to make it fit. I coated everything with epoxy again, so it is sealed up, but it is a shame I had to hack up such a neat job at the last minute. I stacked up 2 1/4" pieces of G10 to span the space I left to access the foremost keel bolt. In the future all someone will have to do is unscrew the G10 and the bolt is clear. All the other bolts are already clear. If anyone doubts the strenght of G10 or it's suitabity for jobs like this I suggest you take a good look at the specs of this stuff. Boatyards are using it for repairs all the time and some of the builders are using it now too. It is good stuff.

plate

Here is the step with the plate installed. The tie rod was permantly corroded in place in the aluminum plate. This made the removal of the plate very difficult. Since my new step does not extend as far aft as the original one, it is much easier to get the plate on and off, even with the tie rod attacked. No need for a BF hammer any more :)

done

Here it all is as I left it for the yard to step the mast.

The only thing I could not do, that will have to wait until next season, was to repaint the bilge. I even bought the paint but there just wasn't enough time in my schedule to get to it.

I have been going at this full bore for a while now. I had so much stuff to do this week that I was out there at 9:30 pm painting my bottom. The paint job came out respectably considering I was painting black on black in the dark!
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Jerry Salaja (Jerry)

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Posted on Friday, June 08, 2001 - 10:15 pm:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

For what its worth. On my boat, when the mast area was repaired the yard used a type of polyethelyne (I think that's the spelling) to replace any wood they took out. They glassed it in. It is usually used for bridge pads so it can take a lot of load pressure without compressing. It is also pretty much immune to rot and water. It was covered with glass and has held up well.
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Jeff Roy (Jeffr)

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Posted on Wednesday, June 06, 2001 - 03:22 pm:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

another photo of my project

my picture
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Jeff Roy (Jeffr)

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Posted on Tuesday, June 05, 2001 - 10:24 pm:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

If it weren't for sacrificial zincs there would be plenty of broken prop shafts. I like to avoid using dissimilar metals whenever possible. SS does corrode when underwater there is no way around it. While SS is an excelenet material it is not perfect.

I only removed tha floor under the mast step, The others all seem to be in pretty good shape. If I notice a lot of flexing this season I may use your suggestion to stiffen up the hull around the 2 sets of double bolts. They seem to be providing the most resitance to keel flexing.

Did you rebuild one of these boats? It would have been great to have had your input when I started the whole project. Things are all pretty wrapped up for this season's project. Time will tell how effective I was. I expect things will prove to be pretty solid.
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Russ Fender (Commodore)

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Posted on Tuesday, June 05, 2001 - 10:18 pm:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

Tommy Hawk

It's nice to see your input to our class board. It would be nice to know who you are! Could you please fill out a profile or at the very least list your e-mail address on your postings. I checked our member list and the information we have on the known S2 9.1's and your name didn't come up. It's appears you have some knowledge on boat repairs and maybe even own a 9.1. In any event if you have any questions feel free to contact me personally if you so desire. My contact information can be obtained by clicking on my name at the top of this posting.

Thanks for your input.

Russell Fender
S2 9.1 Class Commodore
"Sails Call"
Hull #18
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Tommy Hawk

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Posted on Tuesday, June 05, 2001 - 08:14 pm:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

Couple of quick points. Countless boats have SS prop shafts and bronze props without any problems with galvanic corrosion. Countless boats have keel bolts, nuts and washers made of SS without any problems with crevice corrosion. In the unlikely event of a problem, the nuts and washers can be easily replaced with new ones.

Since you're committed to using wood for the floors and stringers, than locust, or another type of wood that's been pressure treated with a fungicide, is a much better choice than mahogany. Mahogany will not hold up well in a moist setting and S2 should not have used it for such an application.

After the old floors and lead keel were removed, I would have laid down about 3/16" of new fiberglass on the original hull surface. I would have started at one berth bulkhead and run it athwartship down into the keel sump and up to the opposite berth bulkhead. I'd use mat and biaxial roving. This new laminate would greatly strengthen the hull and provide a good bonding surface for the new locust floors. I'd cover the locust floors with about 3/16" of new fiberglass and bond it to the aforementioned fiberglass. The whole idea is to build a strong grid that is an integral part of the hull.
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Jeff Roy (Jeffr)

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Posted on Monday, June 04, 2001 - 08:44 pm:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

Certainly there were many options in material to replace this part of the boat. Doing it entirely of glass is a good way to go, but not the one I chose for several reasons.

I wanted to work with material I have experience working with and the right tools for. This made using wood to provide strength a practical choice.

I wanted to use material similar to the original structure. They used mahogony and I chose locust. If they had glassed over all of the wood as I have done the boats would have lasted better. They also screwed up the weep holes which accelerated the problems.

I was not as confident in my ability to build it up entirely of glass and get everything in the right place and be strong enough. I thought about glassing over foam core but was concerned about the compression load. I opted for a very dense material to avoid any risk of compression. I am positive the structure I have built is much stiffer than the original construction and will out last the rest of the boat for certain.

Lots of the boatyards around here are using G10 for all sorts of applications, especially as backing plates. Bronze would create a glavonic problem with the stainless. Stainless would have been a good choice except it will suffer from crevice corrosion if the bilge is wet. It is also difficult to machine without contanminating the edges which only accelerates crevice corrosion.

G10 is almost as strong as SS. It is only going to further stiffen up the sump. Because it is basicly super fiberglass it is a great choice. I fabricated them with tools I had.

I know there are many different ways to do this, but this is what worked best for me given what I had to work with. I not only saved a ton of money by doing it myself, I got the job done two weeks before the yard could even get to it. I would have no complaints if a yard did it this way.
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Tommy Hawk

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Posted on Friday, June 01, 2001 - 09:17 pm:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

My recommendation would have been to replicate what better boat builders have done very successfully for many years. They would have constructed the new ribs and stringers of either fiberglass or fiberglass with a foam core. If S2 had built them that way in the first place they wouldn't have failed.

Why did you use G10 instead of stainless steel or bronze for the washers? No other boat builder does. Again, it's risky to ignore what others have done successfully for many years.

Locust may be okay for a wood boat but it's far from the best choice for a fiberglass one. While I don't know what G10 was designed for, I do know it wasn't designed for what you're using it for.

Tommy Hawk
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Jeff Roy (Jeffr)

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Posted on Thursday, May 31, 2001 - 10:29 am:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

Here is another picture.

plates on

Note the backing plates I made out of 1/4" G10.

I have the fore and aft pieces all cut and fitted, I will glass them in this weekend. The keel is going to be rebedded next week.

Almost home.
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Jeff Roy (Jeffr)

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Posted on Thursday, May 24, 2001 - 08:49 pm:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

I got the new floors made and in place in the boat last weekend. I am very happy with the way things are going.

I cut the floors out of black locust. I just learned about this wood and it is the perfect choice. It is twice as strong as white oak and is virtually rot proof. It is the densest wood I have ever lifted.

I removed one 4" mahogany floor ( I verified it was mahogany ) and replaced it with a new 4" floor and 2 additional 2" floors. One of the 2" locust floor weighed more than the 4" mahogany one!

The only thing that is less than ideal is that the foremost one is asymetric because it was so limitting in work space under the head. The whole thing is so over built now it is not an issue. (I have a habit of going overboard on jobs like this).

I laid them in thick strips of epoxy and put thick fillets on the sides and rounded the tops. I am going to put a few layers of glass over them. One of the only drawbacks of locust is that because of it's densitiy it reportedly does not glue well. I glued up some test pieces and they are pretty damn adhered. Oh well.

The fore and aft pieces are yet to be made. I plan on making these easily removable. The plan is to coat them in epoxy, wax them up good. Bed them in the hull and across the floors in epoxy and lag bolt them in place. After the epoxy is cured I will pop them off. Then I'll treat the bolt holes with epoxy.

I have taken hundreds of digital photos of this project. At some point I will publish a photo essay on it.

The image below is one taken last weekend. The plywood is just temporarily holding everything in the right place.
floors
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Scott Corder (Pastcommodore)

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Posted on Thursday, May 24, 2001 - 02:34 pm:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

Sorry it has taken me so long to toss my 2 cents in on your progress. You appear to be doing very well on your project!!!

Your plans to re-position the "floors" (I've known that term for some time, but nobody ever seems quite comfortable with it...) seem well founded. My only thought (and I'm sure it is already under consideration) regards making sure they retain (and perhaps even embellish) the continuity of the hull's stiffness from bulkhead to bulkhead near the mast step.

Making the keel bolts accessible is also a great idea. On this note: I've recently had opportunity to inspect my bolts and nuts and there is a little rust on them. The yard tells me it is no problem, but it reminded me of all your thoughts on the subject. I have no interest in replacing them now that I have a brand new "grand prix" finished bottom, and have had the keel faired and templated. I think I'll just keep a very good eye on them.

If you get the chance, please weigh your keel while it is off the boat and also make a note of the weight stamped on the top surface of the lead. That data would be very useful to the Class effort to research keel weights and discrepencies. I would expect that the yard could get a fairly accurate weight using their travel lift?

Wishing you continued success!
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Jeff Roy (Jeffr)

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Posted on Thursday, May 17, 2001 - 02:54 pm:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

Update on my progress.

I ended up removing the floor (often referred to as a stringer, but it is a florr) under the mast step. I clung to the hope of leaving it alone and building around it, but when I started to plan the rebuild it became obvious it had to be replaced, not just sistered.

So now I have a very clean work area to start from. I am going to modify the way S2 built the step as follows.

I am going to put the replacement for that double floor about 1 1/2" aft of it's original placement. That will prevent it from covering the fore most keel bolt, I still can't beleive S2 did that. I am going to add a small floor about 2 1/2" foreward of that original floor to help spread the mast compression load. I am also adding a full width floor between the floor I am replacing and the #3 floor aft of it. This will be the aft end of my new mast step. I am doing this to prevent covering the #'3 and #4 keel bolts and to help stiffen the hull at the leading edge of the keel. The #2 keel bolt will end up between this new floor and the one I moved aft 1 1/2"'s. My goal is to create a mast step that will not have to be dismanlted to get the keel nuts off. I probably will never have to do it again, but there is no way I could sleep if I put things back together the way S2 did.

I researched all my options and ended up using Black Locust to make my new floor and the mast step. This wood is stronger than white oak and mahogonay and is virtually rot proof. There is an excelent article about it in this months's Wooden Boat (#160). It grows locally and I found someone who mills it for wooden boat constrction. This is without a doubt the heaviest wood I have ever lifted. I am sure it will add some weight but given it's location in the boat and the function it performs I am comfortable doing so.

I just cut the new floors last night. I still have to glue and tab them into the hull and then build the mast step over them.

My keel is scheduled to come off on or around June 4 and I am hoping to go in the water around June 11.

I have lots of photos, eventually I will put some more on the web.
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Jeff Roy (Jeffr)

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Posted on Tuesday, May 01, 2001 - 04:40 pm:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

Here are a few photos from last weekend.

Photos of my mast step and Keel bolts
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Jeff Roy (Jeffr)

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Posted on Monday, April 30, 2001 - 10:15 am:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

Oh boy!

Just when I thought things were looking promissing, I have been hit with a huge set back.

I took a bizillion measurements and digital photos of the mast step. Then I carefully removed the mast step without damaging the stringer under it.

Now I could see 7 keel bolts.

My bolts have glavanised nuts and washers that are rusty. My hull/keel joint has a little bit of weeping so I wanted to at least repalce the nuts and washers, knowing that at some point the keel may have to be removed.

I almost threw up when I realizes there is an 8th bolt under the front half of that main stringer the mast step was on top of. It was entombed in resing and I only discovered it becuase I was trying to clean out the weep hole in that stringer.

Excuse my language but what the f#&ck were they thinking when they built this?

It seems they put the keel on the boat and THEN buuilt the stringers and the mast step. THEN they put the head assembly down on top of it and then trapped it all under the deck.

As far as I can tell there is almost no way to fix this.

Didn't they anticipate that someone would need to get a keel off the boat at some point? What if you hit a rock?

OK, now I need some good advice from the class, especially those of you that have had to deal with this.

How in the world can you replace that stringer without taking the head out. Taking the head out looks like it can only be done with a lot of damage, more than I want to do.

This discovery has ruined my day! I am really worried this is going to get worse before it gets any better.

I really would like to hear from someoone who has had to deal with this. Scott, you said your boat did not have this forwad bolt, consider yourself lucky!
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Scott Corder (Pastcommodore)

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Posted on Thursday, April 19, 2001 - 08:58 pm:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

Jeff,
Although my memory on some matters is foggy, a few thoughts come immediately to mind:

First, I can't remember if the original stringer under my maststep was one or two pieces. However (a BIG however), it became very apparent to us that the replacement should be a single piece in order to solidify the transfer of loads in as uninterrupted a manner from the chain plates through the bulkheads to the keel. A single piece stringer presents the most inflexible way to accomplish this. My previous descriptions of my repairs should bear this out. Two pieces simply allows far too much opportunity for flex and possible disconnection under the mast step.

Again, we positioned the stringer to bear the load of both the mast and the loads being carried down through the chain plates. I am of the opinion that compression alone does not address the desire of the boat to "fold" in from the sides under pressure from the rigging.

Also, the mast step itself does not appear to experience significant loads fore/aft. Hence, we focused on the downward load primarily. This is why we built the remainder of my new mast step around the new stringer.

All this sort of eliminates the quandry over lag bolts vs. tabbing. The fact is, the mast compresses the step enough to hold it in place to some extent. The stringer is what you want to prevent from moving in any way. If it stays put, everything else will follow suit.

I'll reply to your keel bolt questions in that thread of posts to the board.
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Jeff Roy (Jeffr)

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Posted on Friday, April 13, 2001 - 10:23 am:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

Scott,

My boat is on 5 jack stands, not a cradle, but essentially it is all the same thing. My surveyor and I looked at all of the bulkheads for signs of things having moved and couldn't find any.

I suspect the yard put the keel down on the blocks before they put the jackstands under the boat.

It seems to me that the main stringer at the middle the mast step is actually 2 half stingers which rely on the ability of the mast step to resist compression for strength. The full stringer aft of the mast step seems to only be tied to the mast step by f lag bolts. It may have been tabbed at one point, but I can not find any sign of it now. When you dismantled this area is was this the case?
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Scott Corder (Pastcommodore)

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Posted on Friday, April 13, 2001 - 09:35 am:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

Jeff,
The first thing that comes to mind is this: You may be well served to back-off the perimter pads on your cradle and let the boat "relax" for a couple of weeks (resting mostly on its keel). The reason for this is that a weakened mast step can allow the rig to "push" the keel down and can result in some distortion of the cabin (and the bilge). This may account for some of what you're finding.

The stainless solution I have described on my boat several times allowed us to worry less about how well the mast step area was installed. The primary weight and pressure support is the stringer underneath the mast step (not the entire step). The remainder of the mast step is supplementary to that and far less structural. We built around the stringer with mahogany to complete the rectangle area under the mast plate.

In your case, I'd stick with your "laminated" approach and attempt to make the stringer the strongest component of that area. As long as everything you install is impenetrable, you shouldn't have to tab it too extensively on ALL sides. There is NO way to remove the lav to work there, and I'm convinced it would never be worth it to try. Again, the most critical stress point is where the load of the mast and rigging transfers directly to the stringer (and the keel). This is clearly the stringer itself.

Finally, if you let the boat relax back to its natural shape before performing these repairs, you are much more likely NOT to have problems when you get out of the cradle and get the rig all tightened back down.
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Jeff Roy (Jeffr)

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Posted on Friday, April 13, 2001 - 09:00 am:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

I have had a little ceramic heater with a fan on the boat blowing hot air at the mast step for a week now.

Now that everything is drying up nicely I am finding the integrity of the tabbing holding the mast step to the hull is all compromised. I can get my knife in between the tabbing and the wood structures so I do not think it is doing much any more.

Obviously this entire assembly needs to be replaced with new materials. At the same time I need to replace my keel nuts and washers and reseal the hull/keel join because the factory confirmed the forward nuts are inaccesable with the mast step in place.

My question is how have people tabbed in the port side longitudinal member of the mast step? This edge is under the head unit. It looks to me that taking the head apart would be a HUGE job, not one I want ot do at all.
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Scott Corder (Pastcommodore)

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Posted on Wednesday, April 04, 2001 - 10:53 am:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

Jeff:
While I cannot remember the specific grade of stainless we used on my stringers, I do recall a conversation about corrosion that led to a clear choice being made.

Your concern about glassing these in is legitimate, however the stringers "fit" the bilge in such a way as to make it very difficult for anything to move down there. Yes, we did glass the daylights out of the areas contacting the innner hull. If you recall my other descriptions, my new stainless stringers are actually shaped like an "I" beam in cross section. That means that the bottom of the "I" was in full contact with the inner hull. We glassed over this "ledge" the entire length on each side of each stringer overlapping the inner hul at least 3-4 inches. We left the stainless above this otherwise exposed because we needed to connect the extended keel bolts to the tabs.

The bottom line was that, by bolting the keel to the stringers, the new stringers became "one" with the keel. For the keel to fall off, it would have to take the entire bottom of the boat with it (the keel bolted to three of the stringers). Any random weakness in the stainless/hull connection has been more than compensated for by the sheer quantity of contact surface. It also helps that there are bulkheads and cabinetry in close proximity to much of this work. Remember, we also created small tabs from one of the stringers to the lav and closet bulkheads. Suffice to say, the center of my boat does not flex.

Your choice to use laminated stringers (mahogany?) is a very good one that I might have done had my keel not needed more support. This, in fact, is what we did to reconstruct the mast step around the new stringers. Carbon fiber is also a good idea.

I think anything you can do to reduce the chances of water penetration, compression or decomposition is a good thing. In my experience, no matter how hard anyone tries, a bilge is a naturally hostile environment where there is no such thing as "too few" preventative measures.

Please keep us posted on what you finally do. I'm confident we are not done learning what works best on this repair.
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Scott Corder (Pastcommodore)

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Posted on Friday, March 02, 2001 - 10:56 am:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

John:
Don't despair. Because your hull (#5) is similar in age to my own (#2), I think I may have some info that may help.

When we performed my mast step repair, we probably did a more extensive job than most. We replaced all the ribs in the bilge with new stainless ribs (as opposed to mahogany). One of the reasons we did this was that we discovered my keel had only 6 keel bolts (versus 8 on most others). Most importantly, the 2 bolts that were "missing" were at the extreme fore and aft of the keel. This meant that the keel was significantly more "cantilevered" at each end (fore and aft).

Here is how we utilized the stainless for the new ribs: We fabricated extensions for the existing keel bolts and then aligned them with stainless "tabs" fabricated onto the new ribs. The result is that my keel bolts now attach directly to the new stainless ribs in my bilge (in addition to the fiberglass stub), spreading the load much further than simply the fiberglass stub (it now transers the stress throughout the entire bilge).

You will need to find some folks who are gifted with stainless fabrication. We took special care to remove the old ribs "intact" and used them as templates for the new stainless ribs. The new ribs are actually "I" beam in nature using 1/4 inch stainless strips 2 inches wide at the top ("flat"), and again at the bottom (bent to match the shape of the inner hull), with (2) vertical 1/4 inch elements between (a cross section would resemble the symbol for "pie" with a line across the bottom). The "tabs" were welded onto one side or the other of the "I" beam as necessary to align their respective holes with the keel bolt extensions. The keel bolt extensions were simply larger diameter stainless rod bored and tapped at one end to thread over the exisitng bolts, the other end was externally threaded to accept a larger nut where the extension attached to the new "tabs". It should be noted that we still used the old keel nuts to attach the keel to the "stub" before we "added" the other attachment above that to the new stainless ribs. Suffice to say, my keel ain't gonna fall off without taking the entire hull with it. The boat appears to be VERY stiff and performs like a rocket upwind in a blow.

Obviously, you'll need to repair the damage already done (bummer). We did not have any problems in that respect. Still, the job cost me around $4k. That included alot of time spent figuring this problem out for the first time. Hopefully my experience may be of some use and may help keep your cost from getting out of hand. One advantage to the technique used on my boat would be that your repairs to the glass will not be complicated by their need to carry the huge weight of the keel by itself.

Please feel free to call me if you'd like to discuss this more. Maybe I can fax you some hand sketches to help illustrate our efforts.

Scott Corder
Past Commodore
"Scooter" (former Irish Rose as seen in the S2 brochure)
Hull #2, 1983
616-732-3400
616-866-2670
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John Stefancik (Jstef)

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Posted on Tuesday, March 06, 2001 - 10:42 am:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

Scott,

Your comments were heartening! I have spoken with an experienced surveyor who described this problem as common to many lighter boats with bolt on keels. He told me that it was not the end of the world and that an adequate fiberglass repair job (after grinding out the entire crack on both sides) would be sufficient.

Since I've already had major repairs to the mast step area (including new fiberglass over the ribs, I am hestitant to introduce new keel bolts (thereby adding in another repair $$) unless absolutely needed. However, I did like what you said about your improved upwind performance.

I let everyone know of the repairs when completed.
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Jeff Roy (Jeffr)

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Posted on Sunday, April 01, 2001 - 10:47 am:   Edit PostDelete PostView Post/Check IPPrint Post   Move Post (Moderator/Admin Only)Ban Poster IP (Moderator/Admin only)

Scott,

since I am faced with replacing my mast step and rebedding my keel I am leaning very strongly to a repair similar in ways to yours.

I am not sure I agree with the use of stainless as a material though. Most experts discourage the use of stainless in bilges becuase of crevice corrosion. (SS in oxygen deprived water corrodes quickly). Also most SS is weakened significantly when welded. I hope you use 316L since this is one of the better grades and is designed specifically for use in welded construction.

I am considering laminating new stringers in place using WEST techniques. I have experience with this technique and can do it myself. I am considering using some carbon fiber to make it extra stiff.

I do not think I will be able to tie in the keel bolts using this technique and I assume that was one of the main reasons you went with all stainless. How did you tab in the stringers to the hull. From everthing I have read, acheiving a good secondary bond to stainless is difficult. Did you glass over your new stringers?

Also, what material did you use for the mast step? I am considering one of the high density polymers because they will never rot, do not compress and can be bonded with epoxy well.

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