Hobie 18' Missing Hull Floatation Blocks

Evening Folks:

Have started rebuilding my newest project a 1980 18' with wings.

No sooner than when I took the boat to the car wash to try to start getting some of the almost quarter of a century worth of grit and grime...that I noticed....no foam in either hull.

Now I am pretty sure that Hobie never made an 18' without foam in the hulls (somebody correct me if I am wrong) so I suspect an ealier owner pulled the water logged foam out and never thought any more about it.

Ok gang, how do I put some floation back in? Are there ready made inflatables...or am I going to have to play around with some D.I.Y. foam in a heavy guage plastic bag? Am not comfortable at all thinking about sailing around off shore in Lake Michigan without hulls I know will float...even if holed or worse.

Anybody who has solved this problem...feel free to chime in!

Thanks In Advance,

Poor Paul

Go to Walmart and buy several of the cheap long 'floating noodle' kids pool toys. Cut them into manageable lengths, insert them into the hull port and VIOLA! Hull floatation made easy...they are made of closed cell foam and perfectly suited for this task.

I think we have been through this a few times. Remember you need at least 3 cubic feet (1.5 in each hull) Here are a few options:

1) Easy and expensive 2 floatation bags made for monohulls $80. Call Layline or a Vanguard dealer can help you.

2) Pour Foam - mix 2 liquids and it turns into Styrofoam. Pour through the portholes into a trash bag. You need ~3 ft3 ~$80

3) Styrofoam - cut a sheet into strips that fit through your portholes a 4'x8'x 4" sheet is around ~$20. Look in the phone book and call for best prices


4) Foam noodles - They are on big sale now

5) Super Heavy Duty Beach Toys - They are on big sale now

6) Empty 2l soda bottles

7) Be inventive, go to the discount stores and look in the sale bins. I have heard some good ones over the years. Really cheap life jackets, Foam pool lounge, Giant green foam frog, Puncture proof tractor tire and my all time favorite "The inflatable pool woman". You were supposed to impress your friends by having this strange looking silicone rubber woman floating in your pool. She normally floated face down. I saw 4 of them and a piece of plywood being used as a work raft

Rob:

I gotta tell ya; I don't think there is foam in there! I have a 1990 Hobie 18 magnum and I stuff things in the ports all the time, I've never seen anything like this in the 18s I've dismantled. I do have about four large foam noodles in each hull, though; I originally put them in for floating on when we're in the middle of the lake on a no-wind day with a cold beer in our hands.

Wyatt

But I can atest (please don't ask me how) that a Hobie 18 completely swamped in both hulls and void of air will still stay on the surface of the water....

The Hobie 18's were of a "foam core laminate" in manufacture, which, although it doesn't give a lot of bouancy, it does mean that when the hulls are full of water, they do have minimum positive bouancy

A trick used by some kayakers is to shove a deflated basketball (football?)or two inside a port and inflate.

How can you tell you're missing the foam? Isn't the foam between the crossbeams, like right in the center of the hulls? Can you see that without cutting a hole in the hull, or are the ports centrally located?

Whatever you replace with, keep in mind that: 1. It should be very light and 2. It should resist water absorption

sea ya
tami

Possitive floatation blocks of foam are placed inside of all Hobie Cat hulls. Fiberglass ones that is. On the 18, the foam would be behind the dagger wells.

The blocks are large. Get a stick or something like it and probe through the port toward the aft end. You should find it. If it's not there then someone removed them. How? Certain chemicals will turn foam into liquid and it will pour out the drain holes. Why? To remove weight from the boat.

I am a big believer in building additional flotation into hulls. I was very thankful for the foam blocks in my 18 after an eventful weekend...(see attached photo).

Chris.

I'll bet your boat was a mid 80's model

Looks like a weekend I once had.

You guys might be able to salvage one good boat between ya!

Indeed....1986

Not the first person that happened too eh? Whenever I repeat my story there is often someone else who suffered a hull failure on a hobie 18 of that vintage.

No doubt that was a problem in the late 80's. In 1984 Hobie reduced the weight of the 18. To do this they reduced materials including some "patches" of glass that strengthened the crossbar connection points. Before that... the 18 was bullet proof. After a few years, problems started showing up. Didn't help that we also started adding wings in 1984. Took about 4 years to unwind from that and get the boat bullet proof again. That whole mess was thrown in my lap when I started at the factory doing Warranty back then. I got the warranty extended from 5 to 6 years and the prorated coverage increased to a minimum of 60% over the entire 6 years. Under the Coleman warranty program at the time, the coverage went down 20% per year over 5 Years. 100 1st year, 80-60-40 then 20.

Any 18 in that range should watch the area below the forward crossbar and add reinforcements inside the hull and be retrofitted with anchor plates.

Thats not a bad weekend, this is.....

Oh, and by the way, there was foam flotation all over Biscayne Bay after the "incident" and the boat never sank. I say flotation is critical!

ewre

try www.aircraftspruce.com

Try:

http://www.fiberglasssupply.com/

It costs more if it says Aircraft

To you three guys with photos of broken hulls, how did you do it? I'm in the market for an 18 and your experience has been helpful.

What ever you add to one of these boats needs to be light! Don't fill it up with heavy basketballs or pool toys! Expanding foanm is a no-no because it has a tendency to absorb every drop of water that enters the hull, making the boat heavier and heavier.
Get a strong plastic bag, fill it with styrofoam balls, seal it up and then squeeze it through the inspection port and back past the centre case. Repeat the exercise till you are satisfied you have the reserve buoyancy you require.

Skipshot,
The problem with those hulls occurred mid 80's. Keep in mind while looking for a boat you don't have to avoid a boat of those years. Many of those boats received upgraded replacement hulls. There might be a way to tell if they've been warrantied by looking at the VIN. # on the back of the hulls. Maybe Matt might be able to tell you how to find that info out. When looking at boats check under the shear by the front beam. If you find cracks in the gel coat that extend more than a couple of inches be careful. If they're 10 inches long run away. I had a 81 that I bought in 85 and there were some cracks 2-3 inches when I got it and after 17 years of heavy use they never got any bigger. Good boats.

I saw anchor plates on several of the busted TheMightyHobie18 hulls. Excess load from wings, and lightened boats under design weight....may = trouble.
At a Nationals in Florida, Larry Mondragon was putting his brand new TheMightyHobie18 into the water- weight only 408 pounds! (YAYAYAY- a real winner!) HULL BROKE ON THE BEACH; never even made it to the water!