Formula 27PC Transom Work

[alldodge]

How deep is it from the top of the tank to the bottom of the tank. Let's guess 12". That being said get a 12" sawsall blade {wood blade with rough teeth** and go completely around the tank to separate the tank from the foam. If you have to keep it up an inch then so be it. The tank will be sitting on a "deck" that is not the hull. The hull will be 2-3" below the wood deck. Then try to pry loose like you have been doing. You need to separate the tank from all the sides.

Sorry I must not have been clear, I have totally separated the tank from all sides. There is "no part" of the tank on it's sides which I cannot be able to slide my tool between it and the hull. The foam is stuck to the hull, it is not just sitting there,

Thanks for the tank drawing , but I have the actual drawing for the factory tank from Formula. A new tank with fittings and sender will cost we 1100 plus shipping

 

[kcassells]

Can't wait till you get the tank out to see what the heck is holding it in. Good luck!

 

[tpenfield]

I guess at this point you could use the band iron or similar metal stock to slide in along the bottom of the tank and separate the foam from the tank . . . kind of like a paint scraper (treating the foam like it is paint to be scrapped off the tank).

If you get enough of the foam separated from the rear portions of the underbelly, then you should have enough mechanical advantage using the wedge boards and 2x4's as levers to pry the tank up.

Urethane foam is an awesome adhesive . . . so it is good for installing the tanks, but not so good when you gotta take one out.

 

[Scott Danforth]

too bad there isnt enough room to wedge a deflated basket ball in under the tank, then inflate it. works great for popping dents out of automotive panels that you can not get to. Much cheaper than the eastwood kit.

http://www.globalindustrial.com/pro...dFUfrL9Ckdqv65WapdF2phoC6GDw_wcB&gclsrc=aw.ds

I agree, the foam is a fantastic adhesive

 

[alldodge]

I'll keep trying, may try the port-a-power again, but last time I did I heard some cracking and it was the wood I had it on, Figure with that much force something should have given.

 

[alldodge]

I have the towel at the ready but not throwing it in yet. Cut almost the entire length of the port side plywood out. Took a drywall saw and went down the length. Then pried, banged and nothing, it's not budging.

Pulled my great grand dad's saw out, I have my own but hoping I could get some help, look for anything. Took the saw and went down the entire length of the tank with it. Was going in most all the way down in most places about 2 feet. With this much I could say that half of the foam has been cut from the port side length. Still pry, bang, wedge, the dang thing is not bugging.

As much pressure and force being applied, I'm starting to worry about cracking the hull

Need some more ideas, or some ideas or how to safely cut a hole through the tank to run a chain through it

 

[tpenfield]

Tank is empty (right?) No more straps holding it down (right?)

I would not cut into the tank . . . or even want to use power tools around it. Remember, it is still quite the 'bomb' in its current state.

My only idea, and something that I am not sure I have seen in any of the pictures so far, is wedge boards at both rear corners of the tank pounded in so that they are putting constant upward force on the tank.

With constant force on the rear of the tank, it should give you a bit more daylight to get some scraping or cutting tools further in along the bottom of the tank. It may actually be more practical or effective to scrape the foam away from the bottom of the hull rather than the tank. The whole idea is to progressively reduce the area of the foam that is holding down the tank to the hull.

As you gain on it then add more wedge boards at the corners of the tank to continually keep upward pressure on the corners of the tank. At some point, you could get the 2x4 under the tank and pry upward from the keel.

Keep in mind that the tank probably has 1800 sq. inches of area holding it to the hull and the foam is probably good for holding 5-10 lbs per sq. in. So that is 9,000 - 18,000 lbs of force.

It sounds like you have cut about 1/2 of the area from the access along the port side. So, I would be wedging boards on the starboard rear corner and then wedging some at the port rear corner to see if you can get the tank to start separating from the foam.

Even if you scrap the tank by cutting it . . . you will still have to lift many thousand pounds via a chain.

BTW - I did find a thread on a Bayliner forum (IIRC) where someone did exactly that, cut open the tank to run a chain through, but it did not matter, because the tank was already perforated from corrosion.

Hopefully, your tank will be usable and save you about $1500 total for a new one.

. . . and don't feel bad about the amount of time it is taking to get the tank out . . . my F-242 tank took me 2 weeks to remove. Since it was below deck and I had good access from the deck, I lifted it with a 6,000 lb (rated) scissor jack and a 10,000 lb strap. (I tried a 1,000 lb strap but it snapped and the tank sat there and laughed at me)

Sorry that I can not be more helpful. If I lived closer, I'd be right over.

 

[Arawak]

Ugh, what a PITA!

I don't know if such a thing exists in the length you'd need, but one of those abrasive wire saws might be able to cut through the foam if it was slipped over the open end and worked down the length.

If the tank was full of water, could you use a heated piece of metal to melt/cut it underneath?

Talking out of my @ss, but maybe it will trigger better ideas....

 

[alldodge]

The wedge I sledge hammered in under the port side can not be moved a bit. It's in there tighter then Dicks hat band. The starboard side is pressed directly against the side of the plywood stringer. Have been able to get a saw blade in between but that's about it. This whole project has been slow going trying to save things to reuse. Don't now if that was the best method.

If I could get something under the tank I could pull it outside and connect it to my backhoe. It will either give or rip apart but at least something would happen. Under that same thing if I could somehow get a wire to slide around the tank, it could be used to cut through the foam.

 

[tpenfield]

An additional thought . . . and I made a sketch this time.



If you got:

1. a few (3) 2x8 - 8 footers (wood colored in sketch above)
2. a nylon strap (5,000 - 10,000 lb rated) (blue in sketch above)
3. Hydraulic jack (gray in sketch above)

You might be able to configure a giant lever arm across the tank and provide many 1,000 of pounds of lifting force without damaging the tank. This is a similar method that I used on my 242 tank, but the span I had was only about 2 feet, whereas your boat/situation would require about a 6 foot span. I assume the strap and lever arm would have to be positioned at the rear of the tank, but enough in from the end to have a decent grip on the tank.

You will probably have to put some boards under the end of the 2x8's (and the jack) to distribute the load and go over the 2x8's with the strap and under the tank twice with it so that the 2x8's will want to stay upright.

After that, I think I am fresh out of ideas.

 

[Arawak]

You might be able to configure a giant lever arm across the tank and provide many 1,000 of pounds of lifting force without damaging the tank.

Since he's got a backhoe, I think that would be better, no force applied to the deck. But it seems the problem is getting something under the tank.

 

[alldodge]

Thanks guys, I like your idea Ted but the down side is the starboard side of the tank. For some reason Formula appears to have put another layer of wood on that side, there is no room. I can barely get my saw blade down the side and that is using some effort to push it in. This is the reason I an unable to keep the strap on. Maybe try to design some kind of steel brace that will go under the front edge of the tank at the keel so a jack can be used

 

[alldodge]

Starting to look into safety gear today, have a half face. Found the 3M 6000 series full face mask. Uses the replaceable filters (looking at 2071 P95) my issue is does anyone know how these things are sized? Looking around the net I can find no sizing chart for the face

 

[Tail_Gunner]

Cant see the whole layout from here...good thing to. Your patience is to be admired envied actually. What come's to mind is why that tank is in such pristine condition structure wise......This would be get even time for you to.... actually get ahead time, A through soapy water flushing and then that aluminum tank would be flashing for someone's old barn, I guess when I posted that prayer is was a subconscious thought...time for the tank to go away...

I can tell you I once messed up a foam pour on a deck, about a 2x2 square area on a 4x8 wood insert. The final solution 4 large lag bolts a engine puller.. and sheer carnage. This is almost the same thing id be willing to bet if you lagged that tank up took a engine pulley and tried to pull her out it would lift the boat...no kidding the bond urethane foam achieve is nothing short of remarkable its a bit like separating two peice's of wood that have been clamped and glued...................... Cry havoc and let slip the dogs of war




Just a thought....

 

[tpenfield]

Yea, I was thinking that the backhoe would end up lifting the boat while the tank stays put :facepalm:

 

[alldodge]

Working on an idea of a lifting jig. Angle iron on the bottom under the tank (7in wide base), angles welded to that going up, then another angle on top facing out (jacking face). Put something on the keel to help distribute the weight and use a hydraulic jack. Guess this same fixture could be used on one side to use a twist action and distribution of the load could be wider in that case.

 

[Tail_Gunner]

Yea, I was thinking that the backhoe would end up lifting the boat while the tank stays put :facepalm:

Not really at this point id be willing to bet someone has a bit of pent up frustration. Looking at this person's ability's I can assure you....tank deconstruction is well with in his wheel house.....it would be quick death...maybe.

 

[alldodge]

Not really at this point id be willing to bet someone has a bit of pent up frustration. Looking at this person's ability's I can assure you....tank deconstruction is well with in his wheel house.....it would be quick death...maybe.

I have now yet begun to fight !!!!
OK, settle down, a bit short of breath.... I would say this, if it was not a GAS tank, the saw would have already been out. If I had to do it all over again, I would dig out as much as I could of the wet foam, put a fan on it for a month, re-foam and start the glass work. But cannot do that now with half the tank separated.

 

[Tail_Gunner]

:ranger:.........Carry on my good man..

 

[Scott Danforth]

FYI - from the us composites site

2# density foam has a compressive strength of 40psi, a tensile strength of 30, and a shear strength of 30
3# density foam has a compressive strength of 60psi, a tensile strength of 70, and a shear strength of 50
4# density foam has a compressive strength of 90psi, a tensile strength of 110, and a shear strength of 70

Assuming you still have a 2' x 2' area of 2# density foam, it has a holding force of 17280#

just brain-storming. if you put about 2psi pressure in the tank, it should bulge the sides enough for you to wedge something between the hull and welded corners. then you could put a vacuum on the tank and try to suck the bottom up a bit. maybe you can slowly tear the foam in this manor.