Formula 330SS Bulkhead Replacement

[bigdirty]

Re: Formula 330SS Bulkhead Replacement

Just read through the thread, Looks like a bit of a project, but better you catch it now.. few more years it would have been a LOT worse i think.. and i gota say I'm liking the '90's cad drawings' :lol: although.. I must be stuck back in the '80s, cause I'm still making drawings and plans with a pencil and paper..

 

[tpenfield]

Re: Formula 330SS Bulkhead Replacement

Just read through the thread, Looks like a bit of a project, but better you catch it now.. few more years it would have been a LOT worse i think.. and i gota say I'm liking the '90's cad drawings' :lol: although.. I must be stuck back in the '80s, cause I'm still making drawings and plans with a pencil and paper..

Yup, I am happy to be catching it now. I compare/contrast this boat to my previous boat. I *think* the bulkhead on that boat had some issues when I bought it (at 13 years used), yet I did not discover it until it had really rotted out and spread its 'joy' to the stringers.

I was able to make the 'CAD' drawings by taking some factory tour photos and initially making a 'wire frame' diagram super-imposed over the photo . . . (that is sort of 1980's CAD). Anybody know of/remember "ComputerVision" ??? That was a CAD system that I used briefly in 1982.



Once I had the wire frame overlay, I deleted the photo portion, leaving just the line drawing, then filled in the line drawing a bit to make the final 'solid surface' drawings. It sure helped me visualize the structure of the boat before I started cutting into things.

It is interesting to note that the 'main' stringers only run along the mid-section of the hull, dead-ending at the bulkhead. The secondary stringers are more contiguous, running to the engine mount stringers. I would figure that the main stringers must exert some amount of force on the bulkhead, since they stop there.

Also, I am wondering about the 'lop-sided' support that the main stringers give the cockpit liner (i.e. decking) since the main stringer on the starboard side is 'full height' and the main stringer on the port side is mostly 1/2 the height with a few contact points fore & aft. I was thinking of taking a closer look at that once I finish removing the bulkhead and exposing the rear of the fuel tank.

 

[Scott Danforth]

Re: Formula 330SS Bulkhead Replacement

Ted, that is similar construction to my Cruisers, however I only have a single

are the areas to the right/left of the fuel tank empty voids like my boat was, or are those filled with something? I made two 55 quart coolers to go into that space and access them from deck hatches in the floor. not as easy to grap a beer like a cooler sitting on deck, however works well for us.

 

[tpenfield]

Re: Formula 330SS Bulkhead Replacement

Ted, that is similar construction to my Cruisers, however I only have a single

are the areas to the right/left of the fuel tank empty voids like my boat was, or are those filled with something? I made two 55 quart coolers to go into that space and access them from deck hatches in the floor. not as easy to grap a beer like a cooler sitting on deck, however works well for us.

Hi Scott:

The areas along side the fuel tank are basically 'cavities' in the structure to accommodate storage compartments that are part of the cockpit assembly. However the storage compartments do not come in contact with the stringer support structure; they are suspended slightly over the structure. Here is a mark-up drawing along with some pictures that I took during my pre-purchase survey.

The red lines are where the stringer/bulkhead structure makes contact with & supports the cockpit liner . . . it seems that there is more contact area/support along the starboard side. The port side is largely suspended along its length, having contact points fore & aft.



Here is a picture of view "A" (port stringer) . . . so you can see that there is somewhat of a void, as the stringer does not directly support the decking above in that area.


Here is View "B" . . . the ski locker protrudes down from the cockpit floor (decking) and the waste tank is suspended over the fuel tank.


Here is View "C" , which is just outside the starboard stringer . . . There is a storage compartment that houses the cockpit table & sun pad cushions, and it too is suspended over the stringer/bulkhead structure. The red line shows the contact area where the starboard stringer supports the cockpit assembly above.



Notations "D" and "E" . . . I don't have any pictures of those areas. But "D" is is over the forward port settee (seat) and there is a storage compartment that extends downward for scuba tanks, etc. So the stringer structure is somewhat lower in that area. The cockpit deck is supported at a couple of points up in that area as shown by the red lines on the first illustration.

Then there is the areas marked "E" on both port and starboard . . . it seems that the structure does not extend out to the sides of the hull at any point along its length. It would seem that a fair amount of force gets 'transferred' up to & through the hull/cockpit liner joint, which is the rubrail along the perimeter of the hull.

The boat does not seem as 'tight' as my 242 when coming down hard off of waves . . . So, I may consider doing some modifications to provide a bit more rigidity & support between the hull structure and the cockpit assembly to 'stiffen' it up. Not sure what the rationale for it being the way it is, or any ramifications of changing it :noidea:

Over the past year, I have gone through the structure trying to figure how everything goes together, which is helpful in determining how best to replace the bulkhead and address the moisture issue.

As for the beer cooler, that is at deck level in a storage cabinet below the sink. So, access is quite easy

 

[alldodge]

Re: Formula 330SS Bulkhead Replacement

The boat does not seem as 'tight' as my 242 when coming down hard off of waves . . . So, I may consider doing some modifications to provide a bit more rigidity & support between the hull structure and the cockpit assembly to 'stiffen' it up. Not sure what the rationale for it being the way it is, or any ramifications of changing it

Maybe ask Formula. Maybe it needs the flex to keep it from cracking, probably not but just a possibility

 

[tpenfield]

Re: Formula 330SS Bulkhead Replacement

Ted wrote: >>> The boat does not seem as 'tight' as my 242 when coming down hard off of waves . . . So, I may consider doing some modifications to provide a bit more rigidity & support between the hull structure and the cockpit assembly to 'stiffen' it up. Not sure what the rationale for it being the way it is, or any ramifications of changing it <<<

Maybe ask Formula. Maybe it needs the flex to keep it from cracking, probably not but just a possibility

Yea, I should probably send them an email to see what they say. I hate to 'bug' them too much, since I am not a direct customer, having bought the boat used. However, they are generally responsive regardless.

 

[bigdirty]

Re: Formula 330SS Bulkhead Replacement

A friend of mine bought a 261 liberator a few years back, twin 260 mercs, and the first few runs out it felt a bit loose.. the thing shook and shimmied, rattled, bits of teak were falling off.. quite comical actually.. :laugh:... well, it only got two runs that season, then one motor poped.. turned into full tear down/winter project.. Ended up finding a few similar issues with structure as you are describing, and just seemed like it could use some more strength in a few areas. So we 'stiffened' it up a bit during the rebuild (full gut job, down to the inner hull/glass) and in the end filled most cavity/openings and lower areas near the hull with foam. Was a completely different boat the following season, could take it through a 6 foot roller/swell at full throttle (65-ish mph) and had next to no shudders or shakes.

 

[tpenfield]

Re: Formula 330SS Bulkhead Replacement

Yea, it would be nice to 'tighten' the boat up a bit while I am in there fixing the bulkhead. I sent an email to Formula Tech Support regarding the question about bonding the stringer grid to the cockpit liner. After Googling a bit, I have found that some boat companies specifically advertise that they bond the cockpit liner and stringer system together, making the boat more rigid.

So, we shall see what the folks at Formula say about doing it.

 

[tpenfield]

Re: Formula 330SS Bulkhead Replacement

Yea, it would be nice to 'tighten' the boat up a bit while I am in there fixing the bulkhead. I sent an email to Formula Tech Support regarding the question about bonding the stringer grid to the cockpit liner. After Googling a bit, I have found that some boat companies specifically advertise that they bond the cockpit liner and stringer system together, making the boat more rigid.

So, we shall see what the folks at Formula say about doing it.

I got a response back from the folks at Formula Boats today, and they indicated that although I could 'stiffen' the boat up a bit with bonding the cockpit sole to the stringer grid, it really was not necessary and may cause the cockpit liner to flex in some places that it normally would not flex. So, it sounds like some good advice that I will take into consideration.

 

[alldodge]

Re: Formula 330SS Bulkhead Replacement

Wasn't for sure but thought there was a reason why they didn't. If anything else, these guys know how to build a boat hull

 

[tpenfield]

Re: Formula 330SS Bulkhead Replacement

Wasn't for sure but thought there was a reason why they didn't. If anything else, these guys know how to build a boat hull

Yes, it looks like their reason is that it is not needed and if I bonded the cockpit sole to the stringer grid, I might see some crazing of the gelcoat in parts of cockpit liner as it may flex more than intended.

I may still want to stiffen up the boat, but may do it in a different way; just need to think about it some more.

I probably won't get to work on the boat again until early January, at which point, I'll be taking out the foam from the rear of the fuel tank and cleaning things up for measurement & fabrication of the new bulkhead.

 

[tpenfield]

Re: Formula 330SS Bulkhead Replacement

Winter Update:

I removed the foam from the rear of the fuel tank today. The weather had been quite cold over the past few days, so some of the foam that was holding water was actually frozen. I found that the water seemed to have penetrated parts of the foam, in "veins", rather than spreading evenly across the lower portions of the foam.

Here is a picture of a fairly isolated water 'vein' the I found on the starboard side.


It took a few hours to pry most of the foam loose from the rear portion of the fuel bay, exposing the butt end of the fuel tank and the last few inches of the main stringers. The fuel tank looked pretty good . . . As expected, I did see some darkness (i.e. moisture, etc) penetrating the main stringers, but it looks like it is in a fairly early stage. So, I may try some 'chemotherapy' to the stringers. Pictures below . . .

Starboard side:


Port Side:


I also made a video of the day . . .

Next steps will be to clean up the cuts and to apply some treatment to the main stringers. I probably won't be able to do too much more for a few months, unless there is a winter thaw . . .

 

[tpenfield]

Re: Formula 330SS Bulkhead Replacement

A couple of follow-up questions from what I found when I removed the foam . . . just looking for any thoughts or ideas on a couple of things.

1) The darkness that is starting in the main stringers: My plan is to let things dry out a bit, then 'inject' some rot preventative liquid into each main stringer at the darkened areas. Two types for rot deterrent liquids come to mind; Bleach or Ethylene Glycol (Green antifreeze) . . . any preferences or rationale of one versus the other. Any additional thoughts?

2) The separation of the foam from the sides of the fuel tank: I'm thinking that this should be remedied in order to prevent water from being trapped between the foam and the fuel tank. I was thinking that I could inject either more foam into those areas or perhaps inject an epoxy of some sort to re-bond the foam and fuel tank. Worst case is that I would have to remove the tank and re-foam it. Any thoughts or ideas on the fuel tank/foam bonding?

TIA for any thoughts and ideas.

 

[jbcurt00]

Re: Formula 330SS Bulkhead Replacement

Can't answer the 1st, but for the 2nd I'm unclear how you'd get good coverage on the tank injecting something between the tank & foam that's no longer in contact w/ the tank.

Unless you paint the tank to protect the aluminum, the foam against the tank can encourage water to be trapped against the aluminum. And as seen in several threads, foamed aluminum tanks that have trapped water against them, corrode.

So I'd be inclined to either pull the tank & paint it before refoaming it, or figure out a different method to secure it below decks w/out the foam.

 

[alldodge]

Re: Formula 330SS Bulkhead Replacement

A couple of follow-up questions from what I found when I removed the foam . . . just looking for any thoughts or ideas on a couple of things.

1) The darkness that is starting in the main stringers: My plan is to let things dry out a bit, then 'inject' some rot preventative liquid into each main stringer at the darkened areas. Two types for rot deterrent liquids come to mind; Bleach or Ethylene Glycol (Green antifreeze) . . . any preferences or rationale of one versus the other. Any additional thoughts?

I have heard good things about Git Rot though I have not used it. Buddy has a Regal and has used it in several areas with good results.

2) The separation of the foam from the sides of the fuel tank: I'm thinking that this should be remedied in order to prevent water from being trapped between the foam and the fuel tank. I was thinking that I could inject either more foam into those areas or perhaps inject an epoxy of some sort to re-bond the foam and fuel tank. Worst case is that I would have to remove the tank and re-foam it. Any thoughts or ideas on the fuel tank/foam bonding?

TIA for any thoughts and ideas.

Once the water gets in I don't see anything getting it back out in the area in question. I think the foam acts more as a method of securing the tank from vibrations and most will stick but not all. If it did move it would only be in the slightest. Formula and others have been using this method for a long time with good results, I would stick with the same method. If the water never made it in the first time your 22 year old boat would still be in great condition.

 

[Scott Danforth]

Re: Formula 330SS Bulkhead Replacement

the small moisture that you encountered looks similar to what I ran in on my Cruisers

on the two sections of stringers along side the fuel tank when I did my bulkhead, I stripped back the fiberglass about 2" per side, cut 3/4" off the end.

I then liberally sprayed denatured alcohol on the wood and left exposed to dry out for about 3-4 weeks. I then sprayed bleach to kill any mold spores, let dry. then resprayed denatured alcohol to dry out any remaining moisture. after that I was done with my floor coolers and could put the bulkhead in and tab everything in to seal it up to the best of my ability.

that being said, I would almost cut your bulkhead a bit more to expose the end of the stringer there, and grind back about an inch of the 'glass covering it on the end to allow to dry.

 

[tpenfield]

Re: Formula 330SS Bulkhead Replacement

Thanks for the replies so far . . .

Exposing the darkened wood areas on the stringers by grinding off the glass sounds like a good approach to get it to dry out. Then I could kill the rot and re-glass the tabbing, etc.

The tank is definitely the trickier part. The foam is supposed to be well adhered to the sides of the tank as per the USCG regulations regarding foam tank installation. I suspect that the paint pulled off the tank, based on the fact that the paint stuck to the foam and not the tank. In my prior dialogue with Formula Boats, they indicated that using foam to install the tank provided the most support for the tank and adds strength to the boat. So, I'll probably stay with that approach.

I'm thinking that some condensation has made its way into the 'gap' areas between the foam and the tank walls, but not sure if any problems have resulted yet. The butt end of the tank looks OK, but I will have to pull some of the foam out from under the tank to see what that looks like. I also do not know how much of the foam has separated from the tank. From what is visible, the rear face and the rear portion of the sides have separated. If I decide to 'inject' some foam or epoxy, then I would probably have to make sure it is really well dried out and then bore some holes along the sides in order to pump some sort of 2-part foam or epoxy into and along the 'gap' and have it expand.

It maybe best to pull the tank out, inspect & repaint, and then re-install. (I think our fellow member 'zool' just did something like that). Of course in order to get access to the tank, I have to remove the 'dual helm seat' assembly. I think it weighs several hundred pounds, so I'll have to look into that a bit more.

 

[Scott Danforth]

Re: Formula 330SS Bulkhead Replacement

a piece of 1/4" PVC line line for connecting water to ice makers, etc. and a can of expanding foam sealant works great for getting into tiny cracks 6' long. you can use a piece of heat shrink to connect them and seal the nozzle to the tube

 

[tpenfield]

Re: Formula 330SS Bulkhead Replacement

Thanks . . . I just found on my computer a document that I came across a while back, showing how to remove the helm seat and the cockpit floor. Looks like a 2-3 person job.

I'm not sure at this point which is going to end up being the bigger project . . .

. . . Replacing the Bulkhead . . . or . . . Fixing the Fuel Tank . . . :noidea:

 

[jigngrub]

Re: Formula 330SS Bulkhead Replacement

Hey Ted! I just noticed who the author of this thread was and thought I'd pop in for a looky see. I've been wondering if you were ever going to do anything substantial about these problems besides your "white witchcraft" with the holes, antifreeze, vacuum cleaner, and heaters.

A couple of follow-up questions from what I found when I removed the foam . . . just looking for any thoughts or ideas on a couple of things.

1) The darkness that is starting in the main stringers: My plan is to let things dry out a bit, then 'inject' some rot preventative liquid into each main stringer at the darkened areas. Two types for rot deterrent liquids come to mind; Bleach or Ethylene Glycol (Green antifreeze) . . . any preferences or rationale of one versus the other. Any additional thoughts?

2) The separation of the foam from the sides of the fuel tank: I'm thinking that this should be remedied in order to prevent water from being trapped between the foam and the fuel tank. I was thinking that I could inject either more foam into those areas or perhaps inject an epoxy of some sort to re-bond the foam and fuel tank. Worst case is that I would have to remove the tank and re-foam it. Any thoughts or ideas on the fuel tank/foam bonding?

TIA for any thoughts and ideas.

1. Since the rot in your stringers seems to be in small isolated areas, I would "skin" (cut and remove) the fiberglass off of the area with a decent lap on to good wood, then I would drill out the rot with something like a 1" auger bit in a "honeycomb" pattern. Let the wood dry and fill in the voids with a thin epoxy like the USComposites 635, let cure and then glass everything back in.

2. The fuel tank dilemma is a booger bear! Wet foam/trapped water against unprotected aluminum causes galvanic corrosion... and that aint good! I also suggest removing the tank and painting it, then reinstall with a 4 lb. density expanding urethane foam. The 4 lb. foam is much more water resistant than the 2 lb. density.

I don't know if you've already seen this or not, but it's a USCG circular on Underwriter Laboratories research and testing of below deck metallic fuel tanks:
http://www.uscgboating.org/assets/pdf/recalls/BSC79.pdf