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Deck joint-Who, What and When

Started by Tony G, January 04, 2003, 12:49:05 AM

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Tony G

Those voids look all too familiar.  The ones that didn't open with the 4 1/2" angle grinder got punctured with a dremel tool with a burr bit.  The toerail cavity was attacked with a 4 or 5 inch diameter wire wheel that I mounted on a 6 inch length of all-thread and chucked the mighty power drill.  That pretty much chewed out any unsaturated glass in the cavity.  Before I taped the seam each of the voids were dabbed with straight epoxy and while still in a green state filled with thickened epoxy.  Then the whole seam got another pass with the grinder with much less aggressive grit before washing.  That helped the tape lay flat (as possible) to avoid replacing the original voids with more voids of my making.  Hope that makes sense and helps you out a bit.
My home has a keel.

ebb

You know you might get good info from Commodore Triton his self.  Rob knows more about Tritons than anyone,  and works on them for a living.

Photos show a fine job of prep and the what-looks-like impromptu tabbings look pretty solid and attached pretty good.
Still think that if any of these bandages look suspicious to you, test their adhesion by trying to slip a sharp Stanley chisel under an edge and gently pry on it....see if it wants to lift off.  If you can follow the 'seam' with the chisel, I would assume a bad bond and remove it.
When you see those obvious empty white glass flaps  (you show a patch of small ones)  I'd use the same chisel or a utility knife with a Lenox blade (Irwin has decent bimetal blades)  and just core them out.  See what they covering up.  Fill them with epoxy gell with chopped strand.

The deck in our boats were laminated upside down in a mold.  Most of that lamination is OK.
After it was turned right side up and glued to the hull, any additions (by anybody) had gravity and access going against it.
Tabbings overhead might very well sag and make a 'bubble'.  I found unsaturated white roving in A338.
Tap any suspicious area, if it sounds hollow cut it out, especially if there is a possible leak.  Might have water in it.
You can fill a deep overhead cavity in stages with structural filler, so that the goop doesn't fall out.  Fill it a couple times until flat and  maybe add a piece of cloth to blend it in.

If you have to do it all at once, this I've done for vertical repair with structural gel.
Have a piece of plywood roughly the size of the repair, with a piece of mylar stapled on in.  (Mylar is a 'stiff' film.   Backed by ply, it'll makes an absolutely flat surface when braced over a repair.)  
Prop this against your freshly gooped depression, press firmly to squeeze the filled cavity flat thereby forcing epoxy into cracks & holes (and extra filler out from under the edges of the ply persuader.  If done conservatively, it'll cut your grinding time.)
The trick is to brace it in place with one or more 'spring battens'.  Bendy pieces of fir lumber that are just a little longer than any opposite bulkhead, or stringer, or the hull itself...that you are able to bend the batten slightly between the plywood and a hard place....to create firm  compression.   You want to hold and put some positive pressure on the ply pad...  without breaking the battens.  More battens , more pressure. Pressure is stronger coming from sticks that are just about to straighten out, but can't.

When set, disassemble - mylar peels away - and you  have a glass smooth mirror surface of the filler you used.
You can do this with many repairs, and not just flat (use thinner ply or polyethylene sheet against the hull, for instance).  Big diameter coves can be made with pieces of pvc tube, covered with seranwrap or mylar Thin ply can be bent and twisted - using spring battens.
The technique (if it can be called that)  compacts the bandage/repair, squeezing fillers and fabric,  making a  bond  as good as your prep.... and you get an almost too perfect surface as reward.

I've added epoxy and glass cloth and biaxial any where I thought the hull could use it.
A338 has a consistently thin hull.... that Pearson did NOT make progressively thicker  as they laminated from sheer to keel.  
The Ariel hull is mostly 5/16" thick in the turn of the bilge and keel where the 2500lb lump of lead is encapsulated.   Quality control problem.  

We know  polyester is not water-vapor proof.  Certainly gelcoat is not water proof.  A338 has at least one coat of some sort of 2-part epoxy everywhere on the hull from the water line down around the keel.     Much of the interior is epoxy coated up to the sheer.
Awlgripped topsides were prepped and filled with epoxy. The bottom extensively epoxied from waterline down.
Coating olde raw polyester with epoxy will seal and help support the historic polyester.  Imco it's the best present you give your classic plastic.
Naturally there will be someone who says  polyester needs to 'breathe'.:rolleyes:  Prefer the boat to purrrrrrs.

A nice shiney white 'tank coating' will make those diffricult areas of the boat (forepeak/lazaret) easy to keep clean,  easy to sponge,   easy to illuminate, easy to find sttuff.  AND easy to forget those cheap-shots & blemishes that once stared you down.... when its all shiney white.
However, that is another kettle of....epoxy.

ebb

To go along with Tony's post.....here's my two feet of electric cord.....
I've had success with SANDING SLEEVES, the ones that slide over a 1/4" shank rubber drum
that you expand by tightening a nut (the wrong way) on top.  Not all sanding sleeves are created equal.  
You want best quality mahogany-colored aluminum oxide sleeves in coarse grit, like 80 or 60 grit.
So far, I trust Klingspor* abrasives.   //www.woodworkingshop.com  + 800-228-0000

Find the correct diameter drums and sleeves.   So that you can clean out both sides and 'bottom' of the cove inside the toe rail with the same effort.
 Looks like you can use a range of widths.   Ariel toerail cove was quite even, clean and open, probably due to stingy laminations -and a rediculous attempt at bonding the seam with a stingy layer of fiberglas mat..... that worked!
 Shorter drums are probably more manuverable, and cheaper to replace.
If you jam them  the covers can tear apart....so loose fit is best.  
 Get more than you think you need, because it's rough going for even a well made sleeve.

Imco your best bet tool for this project is an ANGLED DRILL.
I've nearly wore out my old special order 3'8" chuck Milwaukee angle.**  And 100s of sleeves, nearly all coarse grit.  
Klingspor catalog has a generic for $59.95 (TZ20000) that maybe's worth trying.  
This 55 degree angled design is perfect  for  boats.  
You grasp the body of tool in one hand, it becomes a bionic extension with the working end at an ergonomic slant.
-And the angled gear part of the tool is relatively tidy,  allowing you to get IN close and personal anywhere,
 including the tight cove up in the corner against the hull.  
Don't believe a right angle drill has anywhere near the versatility of a half angled drill.
..................................................................................................................................................................................................
Have never figured out how to freehand a stone bit.  They clog or dull or disintergrate immediately.
Equally useless are the conical rasps of different profiles. Too short and dangerous, they come already dulled.
There are carbide coated disks & burrs.  Wouldn't use them where I couldn't keep an eye on them.  $$$ and wear quickly.
...................................................................................................................................................................................................
The Klingspor has other helpers:
3" wide rolls of 80 grit aluminum oxide with cloth backing (like SANDING BELT.)
Make yer own sanding blocks with plywood pieces.  Stick the two together with 2-sided fiberglass carpet tape.
Make reach-in paddles with thin ply and sanding belt on both faces. (Keep yer fingers out of the cove!)
You lightly score the cloth side with a utility knife and snap the piece off the roll.
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Another great tool used on both wood and glass is a Nicholson CABINET RASP #49.
This is a versatile 7/8" wide half-round rasp-file with staggered teeth on both sides, about 12" long OA with about 9" of teeth.
I use it without a handle for every little task.  It's a shame to use it on fiberglass..... but sometimes you have to.
This is a  treasured woodworking tool. Expensive.  A joy to use, doesn't make much noise, and it's always ready to get you out of trouble.
 Don't know who has them right now.  Have to find them  'on sale'  to afford one.
Get three.
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A Fein type oscilating MULTITOOL would be a safer power tool to use.  There are mutiple brands.  Not one of the idiot imitators has come out with a more versatile angled design.  Right angle tools are OK in a right angle habitat, like house or shop.  but have limited use on a boat.  (Exception is the dogleg plunge cutter)
Some have a carbide rasp attachment.  But I found (the Fein rasp) too coarse to be useful.  An imitator may have a mo'betta rasp for  the cove.  I've really used few attachments that came with 'multimaster kit'.

Haven't tried this:  For some of your what-looks-like very narrow coves - maybe carpet taping a loop of sanding belt over a 'dog leg' plunge blade might get into those narrow places.  Possible !
 
[Elsewhere here I've put down the Fein as being WAY  W A Y   too expensive for what you get, not only the power head but its sanding and cutting attachments have insulting prices.  I'd try Harbor Freight. And then look for better bimetal cutters on the internet.  You can see what Fein has in the Klingspor catalog.  Then look elsewhere.  Most after-market blades (Imperial) fit all mutitools. Ocilating multitools are held by the body which quickly get too HOT to handle. Source: forums.]  
If you have a Bosch multi and want a plunge cutter, try their new Carbide Blade OSC114C - actually cuts metal ! :eek:

.................................................................................................................................................................................................
*Klingspore are the progeny of Klingons:D

** McMasterCarr has a Milwaukee  3/8"chuck 3.5Amp 55degree angle drill (0370-20) = $132.50
[Brutilized my 15yearold, never replaced anything, altho the cord at the tool is leaving - dislike gear chucks that have to have keys attacht  to the cord.

Triton106

I stopped by Blossom this evening to test the fit of the Tide's Marine Strong Track I received yesterday. I will post the installation of the strong track and Code Zero furler in a separate thread once I am done with them.  Anyway, it was blowing 20-25 knots gustting to 30-45 in the marina when I got there.  The marina is situated in the Oakland Estruary on Alameda Island. It certainly was not an auspicious night for working on the hull deck joint. But ever since I read Ebb's suggestion I have been wanting to test the soundness of the bonding of the hull deck tabbings with a sharp chisel.  One reason I feel this is important is that when I looked at Vento Dea's hull deck damage I can see that the fiberglass tabbings appear to have been ripped clean off the hull, indicating a very poor state of bonding.
 
 
As you can clearly see from the pitctures below the tabbings between the anchor locker bulkhead and deck on Blossom are also not well bonded. I could almost tear off the outer layer the entire length of the bulkhead by hand. The tabbings between the bulkhead and hulll are in better shape. However, I still would not know if they will survive a knock down by a freak wave. So my plan is to cut out the entire bulkhead and make a new one. I will then reinstall the new bulkhead in a ring of foam cushion between the bulkhead and the hull and deck. In addition, I also intend to install two longitudinal stringers that run the entire length of the v-berth and the anchor locker. As I mentioned before, when I painted the hull a few years ago I noticed stress cracks in the gelcoat all the way around the hull where the bulkhead is. I suspect the lack of the stringers to support the forward hull and the tabbing of the bulkhead directly to the hull are the main reasons for the stress cracks.
 
 

 

ebb

That's amazing.... and instructive!
If those tabbings are factory, ie original, then it's textbook that polyester is not a glue.
And therefore you cannot expect a bond when using polyester resin to tab a cold seam.
If the tabbing was 'after market', and the resin used was epoxy.... then prep, or DFO, or resin, can be to blame.

May have had a discussion on a thread here once about bulkheading (Tony G?).....
The main aguement for 'floating' a bulkhead is that you (hope to) avoid point loading.
In other words, if you install a plywood bulkhead tight to the hull,
you're going to create the problem (like Pearson did), such as you describe with gel coat grazing on Blossom's hull.
The bulkhead is 'photographed' on the exterior hull.  
Textbook technique is to space the bulkhead off the hull by, say, 1/2" and attach it floating to the hull with tabbings.   To avoid the hollow, you'd use 1/2" foam rubber strips to get form fit....and tab away.  But running fillets on  foam gasket could be problematic.

This may be good for major bulkheads.  It definitely spreads the point load.  And would work.....but I'm not total on that.
I'm an egg crating fan,  (mostly persuaded by what I considered is the starved hull on Ariel338) and therefor worked in a number of minor 90degree web intersections with the hull - lockers, mostly in the galley and accommodation.
It seems unneccessary to offset all these minor bulkheads.....with foam.  Because one could argue that there are multiple sharing point loads  spread out over an area of the hull.  
The hull would have to be very thin indeed to photograph web construction thru the hull.   Depends on your definition of egg-crating!

Imco the crazing on your hull comes from the hull being unsupported on either side of the bulkhead.

LittleGull's hull had horizontal hollows on either side of the STRINGER - a  mahogany 2X2 tabbed to the hull about 15" down from the sheer - the stringer stopped abruptly at the main bulkheads: mast and cockpit.  I added  'extensions' to this stringer running into the V-berth forward to the bow - and aft from c'way blkhd to the lazaret blkhd behind the cockpit.  
 litlgull also had vertical hollows on the hull forward of the mast blkhd, where there were no stringers. - extending below the waterline.
Wanted to even the stresses of the stringer's obvious pointload out to the ends of the hull.  Wasn't going to remove them.
A338 topsides hollows became evident when I spent two months endlessly filling, fairing and long-boarding prior to painting.  [Ebb'sGallery pg7#126 & pg10#126.] However the 'bumpouts' on A338 didn't show any gelcoat crazing per se'.  But long-boarding removed gelcoat on all the highpoints.....bulkheads and stringers.
The hull's permanent topography happened when it was being laminated.  But it's fixable cosmetically if you go to the trouble of arduously filling and fairing.  They are, perhaps, more unsightly than dangerous.  Original blkds now have added tabbing,  and all furniture is tabbed or filleted in web or box like constructions.
 
Could argue that a line of gelcoat crazing showing up on the hull is a sign of stress....of glass laminate in the hull stressed continuously,  and might act as a zipper and open the boat up....on a dark and stormy night.  VientoDeo's hull zippered open, not at the seam, but above the seam where glass was forced into a radical  angle to make a flange.....obviously  broken strands of glass there.  They broke during layup 50 years ago.  
Cove fillets are called for where glass lay-up changes direction.
And stopping the tabbing on the hull  is done gradually...tabbing is always stepped to the hull.....espeially at major bulkheads.
It's plausable that a Triton or Ariel rigged and loaded for cruising, punching through waves where it experiences dynamic forces on its quarters,  on its mast and rigging - or yanked by mooring loads - grounding on shore....... can TWIST and zipper open hidden and unintentional construction seams.

Didn't remove major  bulkheads in the Ariel , some sloppy tabbing came off easy, tite stuff I left on.
But both cabin bulkheads in A338 were substantially altered.... the main under the mast (and the lower shroud 'knees')... and  at the companionway where nearly half was removed to create a quarter berth (but with an added  wide  'rib' constructed where the blkhd had terminated.
The cheat was to add wide fillets and mutiple tabbing on either side of the original bulkhead.  Thinking is that would spread the pointload of the original that was glued in hard (without a space.)
This is where bialial tape, or strips, was used.  Did it backwards from norm by filliting first,
then laying in a narrow strip, then wider strip, then finishing with the widest....thereby ending with fairly smooth super tabs.   If you can't do it all at once, dry edges can be reduced/faired - easily if still green - with BACHO 625ergo carbide scrapers.  "Don't go down to yer boat without them!"  
They come with belt holsters too!:D

SUGGESTION for a new major bulkhead:
 I think, altho didn't have the opportunity in A338,  that pointload from a new hard plywood bulkhead  can be reduced or eliminated
by first laying down graduated biaxial strips on the hull where the bulkhead is going.  Eg: 2"/4"/6"/8".
In other words strengthen and support the hull and spread the load befor a nicely fitted ply blkd goes in.  Finishing off with similer graduated tabbings from bulkhead to hull.  Imco strapping the hull like this might enable the hull to resist twisting.  Of course, this is all opinion.
 Using biaxial will allow neat work on compound shapes because you can tease the material ... into neat straight lines of buildup.
Neat enough anyway, so that grinding is kept minimum.  "This ain't no grand piano..." as a carprenter once said to me.
Aye know...aye know...but it is..... Blossom!

Triton106

Been away for a while.
 
I did make some progress in the meantime. I finished retabbing the hull deck joint in the lazarette. After grinding out the joint I filled the low spots (especially the cavities in the toerail) with thickened epoxy. I then retabbed the joint over with two layers of 5" and 8" biaxial tape. I did not take any pictures as I was rushing to get it done but I did spot a couple of white spots which indicate to me air bubbles under the tape. I am a little disappointed by that but overall the joint is much stronger than it was before. I hope I will never have to find if it is strong "enough".
 
In the anchor locker I likewise ground out and then retabbed two spots under the deck that had been poorly tabbed at factory that I mentioned in my ealier post (see pictures in that post). That was straight forward. On the other hand, the bulkhead deck joint was a little more interesting. I was able to pull large pieces of outer tape (weaved cloths) off by hand and was able to easily chisel out the remainer. The inner tabbing was made from fiberglass matt most of which were not properly wetted out (much like the pictures in Vento Dae). I was able to chisel that out fairly easily. For the most part the tabbing came off cleaningly, only a small piece of plywood came off with the inner tabbing. It was so clean that I had a second thought about replacing the bulkhead.
 
Thanks Ebb for the detailed treatise on proper bulkhead installation. A lot of timely and good ideas to think about...

Triton106

As long as I am moving the anchor locker bulkhead I might as well take advantage of the opportunity to address the chain plates which are all original. For reasons I don't understand West Coast Triton lower shroud chain plates are installed longitudinally and are screwed on to the knees which are basically pieces of 2x4's glued to the hull. The main side stays, on the other hand, are installed athwartship and are bolted on to the main bulkhead.
 
 
The knees and the chain plates are then encapsulated in a couple layers of fiberglass. I did not understand the point of the fiberglass until I cut them open. I found out that the knees are now partially separately from the hull. So the fiberglass that encapsulates the chain plates and knees are actually holding them onto the hull. Here are a couple of pictures of the chain plates, knees and fiberglass shell that I cut out. I plan to rebuild the knees and reinstall the lower shroud chain platess longitudinally like the East Coast Tritons and late model West Coast Tritons.
 
 
 


I also cut out the original shelves in the v-berth and plan to install full length shelves from main bulkhead to anchor locker bulkhead. I mentioned in my previous post that West Coast Tritons don't have stringers in the v-berth for some reason. In addition to providing more storage space the full length shelves will also stiffen the hull.

Triton106

As long as I am moving the anchor locker bulkhead I might as well take advantage of the opportunity to address the chain plates which are all original. For reasons I don’t understand West Coast Triton lower shroud chain plates are installed longitudinally and are screwed on to the knees which are basically pieces of 2x4’s glued to the hull. The main side stays, on the other hand, are installed athwartship and are bolted on to the main bulkhead.
 
The knees and the chain plates are then encapsulated in a couple layers of fiberglass. I did not understand the point of the fiberglass until I cut them open. I found out that the knees are now partially separately from the hull. So the fiberglass that encapsulates the chain plates and knees are actually holding them onto the hull. Here are a couple of pictures of the chain plates, knees and fiberglass shell that I cut out. I plan to rebuild the knees and reinstall the lower shroud chain platess longitudinally like the East Coast Tritons and late model West Coast Tritons.
 
I also cut out the original shelves in the v-berth and plan to install full length shelves from main bulkhead to anchor locker bulkhead. I mentioned in my previous post that West Coast Tritons don’t have stringers in the v-berth for some reason. In addition to providing more storage space the full length shelves will also stiffen the hull.

ebb

Don't know if the old adage  'looking a gift horse in the mouth' works here.  It's not about how rotten the boat is.  Maybe it's about which end of the horse we're looking at.

Knees in the Ariel were pieces of exterior plywood (thick lams with voids in the middle - but nicely tabbed) at right angle to the hull which brings the plates up thru the deck also at a right angle to the toerail.
Found that to be backarseward and ended up with macho plates slapped on outside the hull, parallel with the toerail and loads on the bolts.
Read once that the weight of the boat should be able to be supported, HUNG, by the rigging.
Took that as gospel and way overbuilt what littlgull has now.  Probably too much.

Just heard this one...
There were these three guys going to the quillotine during the French Revolution:
a priest, a drunkard and an engineer.  "Any last wish," asks the guillotinair to the first.
"I'd like to go face up to God in heaven, where I'm going," says the priest.  The great
knife falls.... but stops short of slicing his head off.   "It's a miracle!" yells the crowd,
"Set  him free!  Set him free!"  So he is let go.   The drunkard is next, and he says,
"I wanna go to heaven too, face up for me." Same thing happens,  the knife stops
 just befor it chops off his head.  It's a miracle! It's a miracle! set him free!   So he's let go.
Now, it's the engineer's turn.  "I want to go face up, too..!"   Just as the executionor is
about to pull the lever,  the engineer yells,  "Wait, wait, I think I see what the problem is.":D

Triton106

Well this is weird... I just posted this posting and Ebb apparently responded to it and now poof it is gone. So I am reposting it in reverse chronological order with Ebb's posting above. Just like a flash back in a movie;)
As long as I am moving the anchor locker bulkhead I might as well take advantage of the opportunity to address the forward lower shroud chain plates which are all original. For reasons I don't understand Aero Marine installed the lower shroud chain plates longitudinally, screwed on to the knees which are basically pieces of 2x4's glued to the hull. The main side stays, on the other hand, are installed athwartship and bolted to the main bulkhead.
The knees and the chain plates are then encapsulated in a couple layers of fiberglass. I did not understand the point of the fiberglass until I cut them open. I found out that the chain plates are screwed onto the knees and the knees are glued to the hull but are now partially separately. So the fiberglass that encapsulates the chain plates and knees is actually holding them onto the hull. Here are a couple of pictures of the chain plates, knees and fiberglass shell that I cut out. I plan to rebuild the knees and reinstall the lower shroud chain plates longitudinally like the East Coast Tritons and late model West Coast Tritons.
Additionally, I cut out the original shelves on both side and plan to install full length shelves from main bulkhead to anchor locker bulkhead. I mentioned in my previous post that West Coast Tritons don't have stringers in the v-berth for some reason. In addition to providing more storage space the full length shelves will also stiffen the hull.

 

Triton106

Ok, I spent the day cutting out anchor locker bulkhead and removing forward lower shroud chain plate knees. I then started the miserable job of grinding down the thick tabbings of the bulkhead and chain plate knees and sanding down the v-berth and anchor locker as preparation for installing stringers and full length shelves. For those of you who ever wondered what is holding the forward lower shroud chain plates in place here is a picture. Just three size 12 wood screws holding the chain plate to a piece of 2x4 that is considered a kneed - sure is not much.
 

 
Well, finally, I have some good news. I mentioned in my posting previously that the tabbing between the anchor locker bulkhead and the under side of the deck was rather easy to pull out. Not the case with the tabbings between the bulkhead and the hull. I had to cut tabbings with cutoff wheel and then chisel where I could not reach with the cutoff wheel. I pulled and pulled and even gave it a couple kicks but it refused to come out. Finally, I had to cut the bulkhead into two pieces to get the upper piece to come out first. Then I hammered and chiseled to get the lower half to detach from the tabbings which were hard to reach. The moral of the story is that I am encouraged by the tenacity of the tabbings. I dicovered that the key difference between the bulkhead tabbing to the deck and the tabbing to the hull is that the former used what appears to be chopped strands and the later used weaved rovings. The difference in bonding quality if HUGE. I am hopful that the hull and deck joints are tabbed with weaved rovings. Nevertheless, I still intend to grind down the hull and deck tabbings and add two more layers of biaxial (1708).
 
As mentioned I intend to move the bulkhead forward approximately 6 inches. Tritons have a huge anchor locker but a small v-berth. I am 6'2" whereas the v-berth is only 6'0" long bulkhead to bulkhead. Moving the anchor locker bulkhead forward 6" should make the v-berth a lot more comfortable. It will also enable me to install a 20 gallon water tank under the forward half of the v-berth.
 

 

Triton106

LOL... Ebb, that's a good one.  Being an engineer myself I admit us engineers love to solve problems regardless if the problem needs to be solved or not, who will benefit, how the solution will be funded, etc, etc...  I also admit in many ways I approach boat projects the same way - solve problem first, define goal later, if ever.  Sad isn't it?  But you live and you learn.  I am getting better at defining goals first and then finding solutions.
 
I think someone must be eating my postings.  For two days in a row now I have posted new postings and verify that they are posted only to find later in the day they are deleted for some reason.  Maybe they were not posted correctly.  This will be my test posting to see if it will disappear again.

Bill

T106, the subject here is hull to deck, not the restoring of a particular yacht.  Please search to find an appropriate thread for other subjects.

Bill

Peter Theis (Solsken, A-82) wrote the following Email in response to a notification that there were new posts to the deck joint thread.  I believe he wanted this conversation posted to that thread – Peter is asking for comments.

-Moderator
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

Here's a comment from one of my sailing friends.  The crew dropped his Renegade off the hoist as I recall.  That is the fall he is talking about.  He got a new boat out of that disaster.
Peter

-------- Original Message --------

Subject: Re: Reply to thread 'Deck joint-Who, What and When'
Date:    03 Dec 2013
From:    Rex Miller
To:    Peter Theis


Not having seen the joint on your boat it is hard to assess the applicability of the thickness.  On my Renegade the hull turned in and the deck was epoxied to the top of the turn.  Not super thick.  It was thru bolted through a hollow toe rail but the bolts did not go through the deck lip as I recall.  No amount of tightening would stop leaks at the through bolts.  The jib sheet car track was on top of the toe rail, compounding the problem.  The hollow had been filled with a goop that dried over time.  Tightening the bolts just collapsed the toe rail. I fixed the problem by making stepped aluminum blocks with a 1/4 inch step 1/2 and inch wide to address the thickens of the deck section.

The major damage to the Renegade when it fell was at the deck to hull joint splitting for over 8 feet. Within one inch of the outboard edge the deck became cored and was substantially thicker until it reached the coach house turn.  The stability of the monocoque hull relies on the hull to deck joint so relying on a small surface area, of less than a inch wide, of contact area, which to boot would have be a secondary bond.  It was in my opinion a poor and inherently weak design at that critical junction.  The failure described below does not surprise me in adverse conditions.
Had the joint been shoe box joint it would have supplied much greater strength.

The Ariel, Renegade and the Triton were similar designs and had much in common and much to commend them, but not the construction of the hull to deck joint.  The 5200 would add some strength to the joint as it is primarily an adhesive.

On Mon, Dec 2, 2013 at 1:23 PM, Peter Theis wrote:

    I'd be interested in your thoughts on this disaster.  When I rehabbed my  Ariel, the baby brother to the Triton,  I used a Dremel tool to establish a groove outside of where the deck and Hull were joined.  I had had leakage through that joining but never a clear break.  I filled the groove with 5200 to join the deck and hull and close any leaks when the boat was healing.  It seemed to have worked, at least so far.  The deck overlay creating the gunwale where they join is very thin and there is not much for the epoxy or the 5200 to adhere eight at the juncture.

Triton106

Ok, that explains the disappearing posting mystery.  I commend the Forum for its discipline.  At the same time it would be nice to get an explanation or at least a note to the effect.  I literally posted the same postings three or four times thinking that I must have done something wrong in the posting process.