Basic Terms

Monday, March 7, 2016

Cracking The Case


                      

There is something to be said about the allure of a good Mystery-Crime drama. It doesn't matter if it's  fact or fiction, this genre has captured our attention for ages and will continue to do so for many years to come. Whether it's  Sherlock Holmes, Mickey Spillane, or even CSI, it seems as though we just can't get enough of this stuff!  Why? 

I don't think we are entertained by the fact that crime dramas depict a dire situation which usually involves an unassuming or helpless victim... No it's not that...

It's the mystery which surrounds the crime that draws us in. We are problem solvers by nature and simply can't resist the challenge of solving a mystery! 

Just like our next repair. The damage shown in the following photo was somewhat of a mystery to me...


So what makes this so mysterious? It's a big crack and it needs to be fixed. No mystery there...  The real mystery however, is how did the crack occur? It didn't just happen while sitting on the trailer, nor was it a direct result of the pick-axe which caused the cannon ball damage that we repaired earlier. 

I needed to know how and why the crack happened in order to apply the appropriate repair. 
My intention was to not only to fix the crack but keep it from happening again. Some of you may be thinking,why bother? Just fix it and move on to the next repair. Well, that's ok too but It's important to remember that with any type of Restoration or Repair project, there's usually two ways of doing something- 'The right way'  or 'The wrong way'. There's a good example of this later on in the story. 

On that note, how would I figure out what actually happened? I was not there when the crack occurred so I really couldn't be sure what caused it. 

I decided to treat this situation like a crime scene investigation.  I mean, why not, right?
Boat Restoration is so much more fun when pretending to be a crime scene investigator (CSI). 
I figured this would also give me the opportunity to treat my nosy neighbors as criminal suspects!
Now, I know they are not guilty of anything other than being nosy but I thought that if I treated them as suspects they would probably go away faster.  ... Feeling guilty...  ....For no good reason... 
See what I mean? Fun! 

Ok, like any good investigator -before we can crack the case- we need to go back over our original notes.

A few months ago I posted this diagram on our reference page  to help us understand the different parts and locations of a sailboat.


This is a pretty busy diagram and it presents quite a bit of information so we are going to simplify things in order to get a better assessment of the crime scene. 


                       

The crack is located on the left side of the boat which is referred to as the "Port" side. The right side of the boat is referred to as the "Starboard "side.

Now, even though the little guy in the boat looks really guilty, he didn't cause the crack so I eliminated him as a suspect. If you look closely however,  you will notice that he is pointing to the Mainsail... 

Hmmm... 

I took the Mainsail downtown for questioning and -as expected- he immediately pleaded innocent and anxiously provided an alibi. The Mainsail claimed to be on the starboard side of the boat when the crime took place and since the crack was on the port side there was no way he could have committed this crime. I thought about this for a moment and although, it kind of made sense I still wasn't buying it...  After a few more hours of grueling interrogation the Mainsail finally gave up a few of his cohorts.



Boom, Mast, Jib, and Forestay! I knew these guys... They were always in some sort of trouble and I knew just where to find them.

We picked them up at a seedy little joint called "Gales" down on Waterfront . It was a local bar where all of the usual suspects liked to hangout. 

Back at the station I questioned the suspects individually. 

Boom was not the brightest guy in the world but he was a shifty character. His answers seemed to shift in whichever direction the wind was blowing.

Mast wasn't the best witness either and he just sort of stood there. However, He did complain quite a bit about being tied to to the top of the squad car on the way to the station.  Boom didn't seem to mind. 

Jib was somewhat cooperative and corroborated Mainsail's alibi. Apparently, they were both on the starboard side when the crime took place. 

Forestay! Now this guy, he had something to hide. He was recognized as the leader of the bunch and I had a gut feeling that he had more to do with this than what he was letting on. He was taut in posture throughout the entire interrogation and no matter how hard I tried, I just couldn't get him to snap.

Having hit a dead end, I released the suspects and told them not to leave town.

I decided to go back to the crime scene photos to see if there was something I missed.




The major crack is depicted by the red arrow. Most of the cracks that I have found so far have been horizontal. This one however, is vertical which tells me that there may have been an upward force applying stress to  this area of the boat.  The  yellow arrow shows signs of the deck separating from the hull which indicates that I may be on the right track with my theory. I would have to remove the black rub-strip though, in order to take a closer look.



After removing the black rub strip I also had to remove the screws that attach the aluminum track and deck to the hull of the boat. This is a two person job because the nuts that secure the screws are located inside the boat. 



               

With the track removed and a quick hit of the sander you can start to see the severity of the situation. This is not just a surface crack, It's all the way through. What a heinous crime! 

Let's take a closer look at the separation towards the front of the boat.


It's apparent that the forward portion of the deck's attachment holes were literally ripped past the screws at one point in time. The person who discovered this issue simply cut the damaged area out and put the track back in place. This is a prime example of what we were discussing earlier- repairing something the right way or repairing something the wrong way. Whoever performed this repair most likely thought that there were more than enough attachment screws securing the deck to the hull so the damaged holes wouldn't need to be repaired.  

While building a timeline for this crime, I hypothesized that the crack actually occurred after this half-hearted repair was implemented. The upward force that affects this area was not offset by any resistance because the attachment screws were gone. 

I was going to revisit the little guy in the boat! Though, he may not have committed the actual crime he was now considered an accessory. 

At this point in the investigation I have all of the crime scene photos pinned to the wall, some new clues as to why the crack occurred, an accessory, and a new theory regarding the timeline of events. I still didn't have my main suspect though!

Frustration was starting to build but I knew what I had to do next. I poured myself a stiff drink, lit a cigarette and leaned back in my chair. Now, we have all read or watched enough crime dramas to know exactly what happens next. 

There it was... A knock at the the door! 

It was Gale, the owner of that seedy little joint down on Waterfront.  She blew in without warning  as she so often did and tossed a yellow envelope on my desk. 

"Here, now stop coming around my place, you're bad for business!" she blustered. 

"Nice to see you too Gale" I calmly replied.

Gale hated when I was calm. She and I had a thing way back when but it was a stormy relationship that landed me on the rocks. She was gone as fast as she arrived. 

I took a sip of my drink, a long drag off my cigarette, and opened the envelope. It was a grainy picture from the surveillance camera located outside of Gale's bar.

             
                                  


Forestay! I knew it, my original hunch was correct! Let's take a closer look at his rap sheet.

The Forestay is a 3/16" stranded cable that has a breaking strength of over 3700 lbs. It needs to be strong because it keeps the Mast from falling backwards and it's also the attaching point for the Jib. The Forestay connects at the top of the mast and is secured to a chain plate on the bow. This is where the upward force on the bow comes from because the Forestay is in tension (pulling in two different directions). 

                                                       

So, remember how I mentioned that during the interrogation Forestay was taut and wouldn't snap? Well, of course not- there were no screws in the attaching holes which allowed Forestay to pull up on the deck with little resistance. 

But wait a second? He couldn't have done this on his own, he had to have help! 

Mainsail and Jib said they were on the starboard side when the crack happened so the wind force would have had to be coming from the port side. 




That means the force of the wind would have been pushing the sails to starboard causing increased tension on the Forestay.  Since the starboard side had all of its attaching screws, the greater force would have been concentrated on the port side. 

It must have been a really strong wind though to create enough tension to crack the deck.... 
Possibly a ......   Gale?!?!   Oh no... They were all in on it.

I dispatched a paddy wagon to haul in the whole bunch in. While I was waiting I decided to clean up the crime scene. 



I used a cargo strap to draw the bow down as close to the hull as possible. Then I filled the crack and and all remaining attaching holes with structural epoxy. Once the epoxy cured I started reinforcing the deck with new layers of fiberglass and epoxy resin.



The nose of the bow was completely separated and had to be restored.



I decided to reinforce the starboard side as well, just to keep things fair.



First reshape and primer coat! Things are looking up...



On the inside of the boat, I added backer boards which were not there originally. 
This would provide additional support.


This Case Is Cracked! 

Obviously, I had a lot of fun writing this post but there is a serious note to all of this. While, we may never be able to pinpoint the specific events, components, or environmental conditions that resulted 
in such severe damage,  it's important to remember that all three elements play a significant role in the integrity of a vessel and the safety of its passengers. Making the effort up front to learn -or even refresh your current knowledge- when implementing any kind of repair, will always pay off in the long run.

As for the perpetrators, the little guy in the boat ended up getting away never to be heard from again. The judge gave the rest of the gang lifetime probation and appointed me as the Officer in Charge... 

8 comments:

  1. Hello GI-Curious, as a fellow boat owner, I enjoyed your article and hope that I never have that level of damage in my 34 footer. The detective work was superlative although you craftily fed in a false clue because I do not think you knew what the boat was doing when the deck cracked. As an aviation engineer, I want to answer your crack with a crack. Many years ago, an English aircraft company designed a new aeroplane and the test pilot took it skyward. Hearing a noise he headed quickly back to the airfield where it was discovered there was a long crack on the underside of the port wing root. As a crowd of engineers stared up at the crack in amazement, Sam the toilet cleaner walked by. Barely pausing, he said, 'I know what happened there.' The engineers decided to put a stiffening plate along the wing root and once more the aeroplane was taken to the skies. Back it came 10 minutes later with a near identical crack under which the engineers gathered again. Once more, Sam the toilet cleaner walked by and said 'I know what happened there'. 'Oh bugger off Sam,' said one of the junior engineers. The next day the aeroplane took off again with an even thicker stiffening plate, made from high grade, hiduminium but returned shortly afterwards with an identical crack. The engineers stood around scratching their heads as Sam the toilet cleaner passed by. 'I know how to solve that problem,' he said. 'Oh bugger off,' said the junior engineer responsible. Sam picked up his bucket and headed off for the toilets of the flight shed when the chief engineer ran after him. 'OK, Sam,' he said, 'tell me how you'd cure it...' and the chief engineer listened intently before returning to the underside wing. He told the fitters to take off all of the stiffening plates and go back to the original design and then draw a line along the wing root where the crack always appeared and drill a serious of very small holes all along the line. Job done, the aeroplane was taken to the skies again and returned an hour later, undamaged. Sam walked by and the chief engineer called to him, 'How did you know that would work Sam?' 'Well, Sir,' he said, 'I must have handled thousands of rolls of toilet paper and I can tell you, that try as you might, the sheets never tear along the holes.

    Anyway, joking aside, one of the golden rules to prevent crack propagation is to drill a hole three times the diameter of the widest point of the crack right with its centre line right on the end of the crack. You didn't say you did and you didn't say you didn't, but just filling up the crack with glass fibre I feel may only be a temporary repair because it looks to me that there is a stress raiser running from the deck cleat to that hole for the trim. It would only need a badly placed fender and an over-taut rope to initiate the crack. Fortunately, your internal stiffening will save the day. Anyway, I enjoyed your crack and I hope you enjoyed mine.

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  2. Hi Richard,

    Excellent feedback my friend-very much appreciated!
    You are absolutely correct, I really did not know what the boat was doing when the deck cracked which is why I mentioned the following in my closing summary, "...we may never be able to pinpoint the specific events, components, or environmental conditions that resulted in such severe damage..."
    The crack really was a mystery to me but the likely assumption made for a creative telling of one of the many repairs that goes with this project.

    Thanks for sharing the 'Sam the toilet cleaner' anecdote! It's funny, that's the second time I heard it. The first time was many years ago in Air Force tech school... They actually used it as a teaching analogy for exactly what you mentioned- stop drilling.

    Not sure if you can tell, but if you look at the picture where I stated that I was cleaning up the crime scene (you might have to expand the photo-it's not the best quality) you may be able to see where I did drill and fill the top of the crack to mitigate the stress-riser. The photo is post-sanding, following the first cure of the structural epoxy and if you look closely you can see the cross-hair that I scribed to mark the centerline of the crack. Thanks for bringing it up though because I did forget to mention it in the writing...

    Glad you're here with us Richard! Your Engineering and Sailing experience is invaluable and will undoubtedly keep us on the right course throughout this restoration!

    On a side note, I think we share similar backgrounds? I started with Dowty Aerospace who were eventually purchased by Messier-Bugatti.

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  3. Good morning CS! You did an amazing job with the repair...and of course cracking the case. Kudos to you. I may just tune in to your site instead of the next Sherlock Holmes episode. :)

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    1. Thank you so much Diane! I'm glad you enjoyed it! I really did have fun writing it...
      Don't skip Sherlock Holmes... Just read the blog during the the commercial breaks.. Lol

      P.S. Luv the new pic... :)

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  4. You are such a talented man just as I remember!! Great job with the repair. I am very happy for you!

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    1. Thanks for the compliment! You know I only work hard to take breaks! ;)

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  5. So? That's it?
    Kind regards
    Josef

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Comments are welcome