Cave Paintings - The evolutionary History of Ariel #330

Always remember that these are PRODUCTION boats...and that meand hurry-up. You can look in any other production boat for the most part (including those of the brand-new Hunte-Bene-Lina ilk that cost 200K) and find just as much chicken crap in the places they figure the owner isn't too likely to look at or see. There are exceptions, but they are always in lower-production boats for the most part (although my pal's little Vega has incredible attention to detail...well, it is the Saab 99 of sailboats, after all...).

Another friend of mine once observed that old Pearsons are HEAVILY and STRONGLY built boats, ENDURINGLY buitl, even...but not particularly WELL built boats. Fair enough.

I have found parts in my Triton which bear hull numbers a few away from my own, as I did in my Commander, as I did in a friend's Triton. Not too hard to understand if you think about it, I guess...when a build order is issued materials are gathered, grouped and staged, sometimes on pallets, sometimes on rolling carts. Sometimes the boats move to the parts, sometimes the other way around, but there is always gonna be a "hey! where's the ______?" "Dunno, Fred, just grab one off that pallet over there and GET MOVING!!" and that sorta thing. Probably well exacerbated by the fact that the actual hull number is indeed only on that plate and was only assigned permanently to the boat, more-or-less at least, on the boat's way out of the plant. No biggie. Also remember that in all truth and honesty the majority of the Pearson production workers in the old days spoke little or no english and read even less. And drank home made port wine from hip flasks throughout the day as we would drink water at work now. Dead serious.

Dave

Scott, yes,
over time the area in question did change from its original configuration. Many have noticed a sag in the deck under the mast (showing up in an out-of-square doorway) even tho Pearson obviously intended the compression beam and bulkhead to support the downward pressures entirely.

No rot may be present. My theory is that over time wood naturally shrinks. Shrinks a little.
The compression beam, bulkhead, and braces are screwed together without glue. This does not make a monolithic structure (tho, on 338, one relatively easy to take apart.)
Another important observation is that the bulkhead is NOT tabbed to the overhead. Pearson, on 338, made some sloppy allowances for the meeting of the cabin liner, the compression beam and the bulkhead. This definitely was no grand piano they were building. So, I believe there was space fot downward movement anyway.

If you are taking the time and going to the expense IMCO I would restore the area in question to its intended specs. The deck under the mast is a fair curve, after disassembly on 338 it nearly went back to its original shape.
Because of the holes in the deck under the mast 338 had some deterioration in the balsa core. Some deflection there may be evident. Solution on 338 was to cut the core out in way of the mast and replace it with solid fiberglass.*

The top of the whole unit is not attached to the overhead or under the decks. On 338 we avoided the possible tabbing mess by glueing the new laminated beam to the overhead and the ply - and glueing the replacement struts or braces to the ply bulkhead.

I'm not sure that the metal cross brace does anything except stablized a happening problem. If you adjust (rebuild) all the original parts upward or carefully fill the space between the beam and the overhead AFTER the deck has returned to its original shape without any weight on it, and rebuild the doorway etc to squareness, and keep water out, it ought to last another half century.

*the new beam on 338 - and I would think an original one after it has been detatched from the plywood - was snugged up in place - carefully - with a bottle jack. Under the micarta, there are maybe 4 large screws going thru the ply into the beam. Had to use a brace and bit to 'start' them, and winde them out. You may be able to cut the micarta away in a nice curve that matches the beam in the forward stateroom. Jack the beam with or without glue (If you use epoxy on top you don't want to squeeze all the glue out.) , insert some filler (ply) on top of the braces. Replace the micarta with a nice piece of mahogany trim in the cabin. Something like that may be a 'quick fix.' :)

I still have 338's original beam. It has no rot, and still has the nice fair curve it had the day it was put in.

Simply put, the strong back will deflect downward as pressure from the mast increases as the shrouds are tightened when tuning the rig. Since installing the fix on Maika'1 in 1982, there has been no downward deflection in the strongback. (At the time I installed the plates, Maika'i had more than a half inch of "sag" in its strongback.) BTW - this "fix" was designed by an engineer who was an owner/member in the early 1980's.

Thanks for all of the helpful comments regarding production standards at Pearson, hull numbers, and strongback/bulkhead issues.

I have been tearing into my main bulkhead in search of possible damage, and repairing things as I go. I am starting at the edges (top and bottom, and I probably won't go much deeper. I have been chasing cracks, but so far they have led to workmanship and assembly issues that happened forty years ago when my boat was built, and not to damage caused by this recent accident. So I’ll strengthen a few of those things that look odd. This bulkhead and strong back have served three owners well over the years. My somewhat destructive examination continues to show virtually no bulkhead damage from the accident, despite damage to the deck and cabin liner. Both experts that I have consulted here fail to see how through bolting steel plates on either side of the strong back would improve the boat, in as much as in my boat there is no evidence of sagging whatsoever. Once the teak doorframe was removed, the horizontal beam above the door is level. One of the vertical frame members is actually vertical, but the other is not, so that the door opening is a lopsided trapezoid. Since the plywood opening is cut this way and there is no separation from the hull on either side or underneath, I must conclude that this “as built”, rather than “as failed”.

Although the Main-salon-side plywood bulkhead panel is not glassed to the cabin liner, I can see over this panel to what appears to be a glassed seam between the strong back and the deck. I’ll have to take another look at that, but my first glamce told me that this seam was solid and not indicative of any sag or separation. I could have concluded that from the V Berth side by looking at the seam between the strongback and the underside of the deck, but I have not removed the paint from that area, or relocated the many wires that are clamped to the strongback on the V Berth side. However, the area above the plywood on the Main Salon side of the bulkhead is unpainted and looks as fresh and solid as the interior of Ebb’s rebuilt boat.

So the cracks that I am chasing and the voids that I am discovering were probably left by the builders (the failure to wet out tabs holding key braces in place, voids in the fiberglass, the use of AC plywood with significant internal voids, etc. So I would have to say that my boat might have been both hastily built, but it was also overbuilt. It's sort of like a Sherman tank built by the low bidder. This is one strong boat, albeit one built somewhat strangely in places.

Because it is conventional wisdom to strengthen the strongback, I will continue to explore options to do this, although I can find no evidence whatsoever in my boat that there has been any downward sag in the strongback. I very much like Sirocco’s treatment and may pursue a similar design, but I am also exploring a retrofit paralleling Ebb’s design, but without the tear-out. My thought is to use unidirectional cloth or 20 weight triaxial cloth (not an original idea on my part, but one suggested to me) glassed onto the bulkhead and or strongback in a sufficient number of layers to reinforce the strongback/bulkhead without drilling holes through it. This would allow the strongback to be glassed to the deck also. This would also permit filling of the void above the plywood section of the bulkhead on the main salon side that was originally filled by that strange foamy wire-reinforced trim piece. That piece was glued into the void above the plywood. Those little wires are sharp and hard to remove. What the heck was that stuff anyway? Hmmmmm?

So anyway, my problem currently is not a sag in the strongback, but is instead a compressed and crasked deck and cabin liner that did not result in a failure or sagging of the strongback. The top of the deck is depressed in the vicinity fo the mast step. The mast base is damaged, and the mast step plate is lifted from the deck in the front and driven down into the deck in the back. Two bolts attaching the tabernacle mast step were driven through the cabin liner behind the main bulkhead. The solution to these problems will be chasing all cracks in the deck section (top), and then replacing all of the damaged glass and core with solid fiberglass and fairing it all out to match the rest of the cabin top. This will be done from the topside. The bottom side will also be delt with by chasing cracks, and replacing and reinforcing all damaged glass, then tying the liner, and deck together to the reinforced strongback.

Speaking of tabernacles, last Friday when sailing his boat, a friend had his tabernacle rig fail. His mast dropped all the way down and smashed into his bow pulpit. All three of the attachment points failed (two fixed eye boat snaps on the bridle and the other, a Shaffer snap shackle on the main sheet block failed. The original boat snap that failed was undersized for the load in my humble opinion, but there could have been a defect in the part. The fracture was either not a clean break, or there was a void in the metal at the site of the break. Only one half of the part remained to examine, so I could not tell which was the case. The resulting asymetrical load tore the Shaffer mainsheet block shackle apart. The Pacific Seacraft 25 has a much shorter mast than the mast on the Ariel.

Someone could have been seriously hurt on this fellow's boat last Friday. I examined the broken parts today. The metal attachment snaps sheared in half and the Shaffer mainsheet shackle did as well. It was both lucky and a testimony to the quality of the boat (a Pacific Seacraft 25) that no serious damage was done to the boat beyond the aforementioned shackles and attachment clips. I never would have guessed that the failure of one of the bridle attachment points would so overload the rig that the Shaffer shackle on the mainsheet would break.

Is not a problem, Scott.
Only a matter of level of involvement,
and talking it over with a couple of guys or gals.

You have to remove those two screws that held your mast step on.
You then let (or persuade) the deck to return to its undeflected self.
See if the composite core is ok.
You should make all skin repairs and patching first.
In other words I would do all the cosmetics first (except finish) then stabilize the deck over the beam. You may be saying in what I read that you don't have to do that. That is quite true - you won't drive that mast much further into the boat. But it would look a lot better without the flattening of the liner which could be pushed back up again. "Shippy" is the word.
You can invisibly repair the crack in the cabin.
Then access the mast compression beam shrinkage problem.


IMCO you could probably get by by carefull shimming, carefully fitting in long shims above the beam. AND YOU PROBABLY COULD DO IT DRY. Without fabric and glue. Tho an easy glue to use (assuming you'ld be shimming with long thin wedgies of something like white oak or mahogany) is Titebond II. Without taking anything apart.

I'm not an engineer, IMCO if you fill the top in, you don't need the metal stabilizing straps. Each boat is different, each with it's individual problems. If your bulkhead and beam are in good condition, it is not a problem. You do have to have access from the V-berth side, not the salon side, to put in those shims Good luck!

By the way, I have not done this myself. You have invented the process so that we can see your results - in those bitty pics you post!

Well, like I say, I will further meditate on the strongback issue, but there is no compression in evidence there. It appears that the deck section itself absorbed 99% of the impact, with the remaining 1% resulting in damage in the main salon side cabin liner as a result of the fact that the two bolts that held the tabernacle deck plate in place were pushed downward which caused a deflection and crack in he cabin liner.

The solution wil be to completely remove the deck skin and the core and build a new solid fiberglass deck beneath the mast and above the strongback. The extent of the damage to the laminate will dictate how larger this new solid fiberglass deck section wil be.

There is nothing to shim from below, because the beam as far as I can tell is “as built” with absolutely no sagging and no separation of depression caused by the impact. In other words, the strongback ably withstood the force of 6000 + lbs (boat plus three crewmembers and gear) coming to a sudden and complete stop, with said force directed at the six by ten inch tabernacle mast step directly above said beam. Now in all fairness, since the mast was lowered to shall we say 45 degrees, the force was diagonally aftwards, and so the rear portion of the mast base plate pressed into the deck at a location behind the strongback, and this is where those two bolts penetrate the cabin liner. We wil be repairing that area.

So whatever reinforcing I do to the strongback will be in the way of preventative maintenance rather than remedial maintenance, and I am struggling with that issue because after nearly forty years the strongback appears to be as good as new. So despite the intuitive benefit of adding some stainless steel plates, the dis-benefit of drilling holes through what appears to be a perfectly functional strongback for any reason is also a concern. That is why I like the idea of a non-invasive approach such as beefing up the area with a laminated section of unidirectional or triaxial cloth to replace the Formica on the top of bulkhead on the main salon side of the main bulkhead and wrapping that around the strongback to meet an equivalent reinforcement on the V berth side of the strongback.

This forum is so very useful to me in the process of maintenance and upgrading of my Ariel, that I am almost overwhelmed by the responses and the years of experience that the members contribute to mutual support. Your Gallery thread alone Ebb is a wonderful resource. For those of us who are not inclined to tear our Ariels limb from limb and rebuild them, (unless we have to do so of course) your thread is like a short course in Ariel anatomy.

All your questions have been answered.

Every cavern should have a few dripping springs and some turquiose pools, don't you think? If you are wondering what sort of valve this is, see the "New Fangled Hose" thread in the Technical forum.

A few lines from "A Sailor's Yarn" by J.J. Roche....

They bored a hole below her line to let the water out
But more and more, with awful roar, the water in did spout.

"With simple shackles costing forty bucks, and the basic no-chart GPS running $200, why would anyone voluntarily select an in-line ball valve over a seacock to save forty bucks. A two-inch hole in the bottom of a boat is a formidable thing to face at sea."


Or at the dock!

Look. the yard is not going to admit to any wrong doing. Like a police investigation of a police shooting of an unarmed citizen.

Bill is correct, I'll paraphrase: There is the best way (flanged seacock) and the ok way (ball valve). It is possible, probable, you will find anecdotal support for your installation. However, that ball valve depends entirely on the thruhull for its strength. You, they, the experts, can't get away from that. When you turn the handle, it being at the side, you are putting forces on the fitting that couild crack it or bend it or unseat the thruhull.

A seacock installation protects the thruhull and therefor protects the boat from sinking.

I would only trust a yard or a surveyor who can spell out impartially all your options. They may very well be influenced by your desire to be correct.


You photo does show a nice fat backing block which helps in supporting the thruhull.

Ebb's right--

No one, certainly not a boat manufacturer, a yard/installer, the surveyor who recommended the yard and/or personally felt it was just fine...is going to say that in the interest of a bit more profit and productivity that they have installed/added/recommended/sold to you something sub-par. I mean, no one is gonna say that!

There is a defined reason for proper seacocks...Llloyds' standards are VERY specific about it, and I mean the Lloyds standards for small craft insuranve here. To my understanding ABYC standards were pretty specific too...if nothing else, at least about the hose.

You gotta watch surveyors, too. In most respects, you or I or my dog spot can go out and print business cards, hang up a sign, and be a marine surveyor...it is not a regulated industry. This I get from a friend of mine who is a very talented marine surveyor. He also advises me that there are a lot of surveyors in this world who will tell the pleasureboat owner what they want to hear rather than being the contrarian, as repeat business and word of mouth do depend more on warm-fuzziness than accuracy in a lot of cases---at least in the minds of the unscrupulous.

If, for example, I do a lot of business inside a certain yard across town...and if, for example, they have the ability to either recommend me or talk trash about me...or just take me off the "approved contractors" list...I may think or even know that I would not let the crew over there haul and block a dinghy of mine so to speak, but I can't be running around saying it loudly. For that matter, I could be the very worst contractor they ever saw, but as long as I make the customers FEEL good and as long as I keep sliding 'em the referral fees...they will keep on handing out the cards!!! Sorry to seem cynical, but I see this all the time and it is just a matter of how it works. You can't walk into the liars' club and expect someone to tell the truth!

This is not to say that there are not good yards, good yard crew, or honest surveyors to be had in the world--there sure are, and I am glad to know the ones that are who I am fortunate to know. For every one honest and forthright outfit or person, though, there are a gaggle more who are looking to gouge, get-over-on and generally decieve the customer as this is traditionally how the money is made from the pleasureboat community! That's gone on for years and years, but in the main this sort of thing is a cancer that sweeps all bounds of our society anymore.

Agent Mulder has it right: Trust No One. Especially when they are making money off of you and your boat.

OK, off my soapbox.

Dave :eek:

Interesting philosophical musings my friends. Confucius said one picture is worth a thousand words. So here are two thousand words. I do think, however, that yards would make more money in parts mark-up and labor by installing sea cocks unless built-in obsolescence of the ball-valve-to-thru-hull option brings boaters back sooner for replacement or repairs.

Confucius said one picture is worth a thousand words. So here are two thousand words. But first a few dozen words about the two thousand words:

The first photo is the outside of the thru-hull removed from my boat today. This was my second haul-out this month and was solely to replace this thru-hull. The thru-hull was installed as a new part this month. Note the green corrosion on the shaft.

The second photo shows the interior. You can see a faint line about a quarter to a third of the way down the barrel, which the yard and I presume is a castling flaw (crack) that occurred during manufacturing. The crack is not parallel to the bastard (supplier’s term for non-standard) NPS (straight) threads, but it is at the precise location of the corrosion stain on the outside of the barrel.

The haul out today was at yard expense since they sold me the part and did the installation. My third haul-out scheduled for tomorrow is also at their expense. But this time we have a different sort of leak in the same cockpit drain assembly. So I really don’t think yards save money by installing inferior products. I think that they try to so their best to keep pace with the market and keep their costs and risks in line. Usually the stuff they install seems to work, and it doesn't come back broken very often, or so my yard say about their ball valve to thru-hull installations. However, I am with you guys. Sea cocks are a better way to go for a number of reasons. This cracked thru-hull shaft would have been inside the barrel of the sea cock, embraced by NPS sea cock threads and downstream of the valve rather than above it.

Now, considering the crack, calculate the structural integrity of the exposed section of this thru-hull as pictured in place below the ball valve in the photo above.

This is the promised phtoto number 2. The faint green line is the business end of the thru-hull leak.

Can't really SEE the crack or the green line inside the thru hull. If not a trick of light it looks like some of the threads are galled on the top of the fitting. If this is so, you might share your research with the yard. It means the Taiwan tail was not a match with the Malaysian ball cock.

If those two pieces were hard to get together by the installer because of a mismatch between the SOB and the bastard threads, then it was the installer that more than likely cracked the fitting. And caused your leak. Right, blame it on the fitting!

I'ld wager, despite pipethread letters and numbers, you'ld better use a thruhull made by the same manufacturer as the valve. You'ld be more likely to keep galvanic action at bay because the alloys might be a closer match. If you're lucky. Parts come from all over the world now - nobody knows brass from bronze anymore either.

So far as I know there is only one maker of Marelon. The parts ought to match. The stuff has gained a pretty good rep over the decades. You can get a ball valve or a seacock. Don't think there is much of a price break any more.

Look how thin than wall is with the threads cut in it. Scarey, huh?

Ebb,

Sorry that very thin line 1/3 of the way down shows up only as a hairline. I can see it plainly, but I know what I am looking for, because I have seen it up close and personal. Here it is blown up a bit in the photo below. This "crack" appears to the yard experts and to me to be a casting flaw. Upon close examination it corresponds precisely with the corrosion stain on the outside of the threads as shown in the above photo. The leaking occurred precisely at this location.

The ball valve and thru-hull were made by one and the same manufacturer. The thru-hull valve has bastard (supplier’s term for non-standard) NPS (straight) threads. The ball valve has NPT (tapered threads). By their very nature the two thread designs are not the same, but they are intended by the manufacturer to go together turning by hand for 3.5 turns and tightening mechanically from there. I spoke to the manufacturer's engineering department personally to obtain this information. I use the term manufacturer loosely, since I believe that this manufacturer is actually a supplier who may actually procure the parts elsewhere, but my yard endeavors to match thru-hulls with ball valves from the same manufacturer.

Anyway, I spoke with the manufacturer’s engineer, and he told me that it is possible to "ring off" the thru hull by over-tightening the nut, however, this crack was above the nut in the exposed part of the thru hull as you can see from the horizontal green corrosion stain in the "as-installed" photo several photos above on this thread.

After this experience and a few days of obsessively playing with various thread designs, I am more convinced than ever of the time worn wisdom favoring flanged sea cocks. As a result of my new found devotion to flanged sea cocks, today I experienced my third haul-out in less than a month for a replacement of the cockpit thru hulls and ball valves with Groco full flow flanged bronze sea cocks with bronze handles and matching Groco thru-hulls. One of those Groco sea cocks is pictured in the second photo below. Just looking at it gives me a much greater sense of personal safety.