Center stringer? Do I need it?

[GaJeff]

I'm redoing the deck and stringers on my 81 citation 19.5'. I have a center stringer and was wondering if I need to put it back. I feel like its going to be a problem for water flow. Can I not just do the two sides and a few bulkheads between them and call it good or go back with what I have?

 

[electric603]

Re: Center stringer? Do I need it?

The safest way is put it back the way it was originally designed. The stringers are structural and if you hit a big wave or even a stump or something the hull may not hold up without the intended support of the stringer.

 

[jbcurt00]

Re: Center stringer? Do I need it?

Yep ^^^

 

[Woodonglass]

Re: Center stringer? Do I need it?

Uhmm, What water flow??? If the deck is sealed properly and the boat is maintained properly, there is not supposed to be any Water flow below deck on a fiberglass boat!!! Put it back exactly like you found it. It lasted 30 years, and you'll do it better than the factory so it'll prolly last 50 years.

 

[Yacht Dr.]

Re: Center stringer? Do I need it?

I'm redoing the deck and stringers on my 81 citation 19.5'. I have a center stringer and was wondering if I need to put it back. I feel like its going to be a problem for water flow. Can I not just do the two sides and a few bulkheads between them and call it good or go back with what I have?

By the time you have glassing the dual stringers .. your going to be ok with that option.

I think your 20 footer will be a tank after a proper dual stringer/bulkies design again . .. after the glassing.

Do what you wish but make sure its at least stronger than the OEM.

I dont know why MFG's put stringers right up the spine/bilge of the build myself.

YD.

 

[GaJeff]

Re: Center stringer? Do I need it?

Thanks for the replies. It's just that most of the rebuilds I see don't have this center stringer. It kills my option for a floor mounted fuel tank. Right now the tank is a stand up design at the port side of the transom. I really want that floor tank and a ski locker. And I know water isn't supposed to be in there but if something happens I feel the water will not flow properly. As I started doing the floors I found the front motor mount wood was gone... just like the rest of the deck so I pulled it. That led me to the transom which is just fluff anyways. So now I'm doing deck stringers and transom.

I was planning on making bulk heads to tie everything in, and since they are all out I can make it as strong as needed.

Has anyone used the quad glass before? I found a really good deal for a roll of it and was thinking about using it. I'm not much of a glass layer so I'm not sure what's good or not. It's 37oz. Seems thick enough to lay a single layer but I'm not sure. Any advice on the quad?

 

[Woodonglass]

Re: Center stringer? Do I need it?

Did your boat have foam flotation in it? If so are you planning on putting it back? Is she an I/O or and Outboard? There's a lot to consider when mounting a tank below deck. It really helps us to help you if you could post some pics of what you are doing.

 

[GaJeff]

Re: Center stringer? Do I need it?

Im having a hard time uploading my pics at the moment. let me figure it out and ill post pics.

Its an 81 19.5' citation bowrider with mercruiser 120hp and MC-1 drive. It did not have any foam in the floors, although i would like to go back with pourable if the budget allows. it has foam only under the top cap and in the bow from the cap to the keel. i already have a nice 50gal. tank and it will fit perfectly between the stringers, minus the center stringer. What kind of considerations am i looking at with below the deck tank?

Jeff

 

[electric603]

Re: Center stringer? Do I need it?

Easiest way to post pics is to start a photo bucket account and post them from there.

 

[Woodonglass]

Re: Center stringer? Do I need it?

What kind of considerations am i looking at with below the deck tank?

Jeff

Installation of a Filler Tube, Ventilation tube, Space between deck and hull, proper installation and securing tank to the hull. All can be done...just need to be well thought out and planned. Not sure how large your previous tank was or this one is but a larger tank means more weight to the back of the boat which can cause changes to the way the boat handles and performs.

 

[GaJeff]

Re: Center stringer? Do I need it?

I've got a rough plan on the tank install. Larson make a citation that looks exactly like mine. Not sure if mine is a Larson or not because it just says citation on the side. I'm using that layout for my tank install. It is a 22gal tank and the hoses run along the stringers and up the back of the boat.

My old tank is 19gal and when it's full it throws the weight off bad being its installed on port side of the transom. I'm going to center this one for better distribution.

I'm planning on using that quad axial glass for the install is that a good glass to use? And I'm still working on these pics. My iPhone takes them to big and I'm trying to resize to post

Jeff

 

[jbcurt00]

Re: Center stringer? Do I need it?

Never heard of quad axial glass

Was the tank to port to help counter your weight when solo in the boat? Maybe.

Was it 100% responsible for the port list? Also maybe.

Will a low & centered tank help 'right' the boat's list? Again, Maybe.

Was the port list at rest only, more or less list at idle, 1/2 throttle, WOT? Or no change?

Some tin & glass projects have loaded the boat w/ approximate weights & placements of weight to mimic how the boat will float once finished. 19gal vs 22gal of fuel is @ 19lbs +/- variation, not much.

You might try a float test to see the impact of the placement of the tank. 20lbs isn't much additional weight, it'll be how the change in location affects the boat & it's handling.

Handling can't really be addressed w/ the boat gutted though. But if she floats, moving weight around may help you find the best combination of weight & it's placement.

W/ the fuel at the stern port side, where was the battery(s)? Moving them also, may help counter some of the change in tank location's impact, particularly if there was more then 1 marine battery.

You don't mention any waterlogged foam, perhaps it caused the port list?

I don't know if you've pulled all the below deck structure yet, but you don't want to do a float test w/out the support of the stringers, and the cap secured in place.

 

[GaJeff]

Re: Center stringer? Do I need it?

None of the foam was water logged. Probably because its under the cap and not really touching the hull at all. Not sure why there wasn't any foam added to the deck but I would like to put some back. All the wood on the other hand is completely water logged and rotted. It looks like there was no effort at all in glassing these stringers. I have the two main stringers and a center stringer that the deck mounts to. Beside the mains I have these 1 1/2 x 1 1/2 pieces that go transom to bow rite under where the deck meets the hull but the aren't tall enough to actually touch the bottom of the deck and port side is 3 pieces and star is 4. Almost like there wasn't enough wood to go the whole length so the spread it out. They're rotten and will be replace with something different that WILL touch the deck. Outside of those is 2x4 or 3x4 and those are at the chine. Since that wood is so high it's perfectly fine and solid. No moisture at all.

At a stand still the boat tends to list starboard, on idle and plane it switches to port. This is riding solo. I have 2 big truck batteries on star side. That helps out a good bit but the stern is just to heavy. I bring this big cooler with me to put at the bow to keep it down when I'm alone. I'm hoping the 50gal tank in the middle will help level this out.

The quad axial glass I found is 50"x20' and its 37oz. Weighs 25lbs for that roll. I haven't gotten a whole lot of info on it or feedback from others who have used it but its pretty solid stuff. I wanted to do my transom and engine mounts with it.

Jeff

 

[Woodonglass]

Re: Center stringer? Do I need it?

I've been trying to research the Quad Axial glass fabric ever since you posted about it. All I've found so far is that it's used a lot in the manufacture of the large windturbine blades and Large Yachts. I suppose it would be ok to use for your transom and motor mounts but I suspect it might be hard to wet out and conform to shape but...I've been wrong before!!!!

Since you have no foam issues and you've had a large tank "Off Center" in the boat already, I suspect that mounting the tank as you desire might actually help your boats performance. 50 gallons of gas will weigh approx. 450 lb + the weight of the tank. What motor does this boat have?

 

[GaJeff]

Re: Center stringer? Do I need it?

Yea I figured since it was 37oz that it would be difficult to work with. I guess I was going for strengh. I know 1708 is a biaxial and its also expensive. So quadaxial would be stronger with less layers... Maybe? Or would I still need to do multiple layers. It has one layer of chop strand and the other side is the 4 direction cloth. I got 20' that should be enough to do the transom and engine compartment.

The engine is an 81 Mercruiser 120hp 4cyl. The outdrive is an MC-1 190 ratio. I get great fuel economy and the tank is plenty for this app. but since its a standup type putting that one in the floor is not an option. I bought the 50 at the end of last season in prep for winter tear down but I was busy with other projects. Since I stepped through the floor last week it's time. Not to mention the safety hazard.

I swear I feel like my motor and drive is going to fall out the back of the boat so it's time

And I'm just going to get a photobucket link for the pics

Jeff

 

[Woodonglass]

Re: Center stringer? Do I need it?

1 layer of 37 oz should be adequate. I would really like to see a pic of it. I still think that 50 gallon tank might be a bit much. That's a lot of weight.

 

[GaJeff]

Re: Center stringer? Do I need it?

I'm trying to get these pics. My uploads keep failing. I've posted pics before. It's even failing on photobucket. I don't know what's going on. If its on my end or not.

Ill get back with you guys

Jeff

 

[jbcurt00]

Re: Center stringer? Do I need it?

I've got a rough plan on the tank install. Larson make a citation that looks exactly like mine. Not sure if mine is a Larson or not because it just says citation on the side. I'm using that layout for my tank install. It is a 22gal tank and the hoses run along the stringers and up the back of the boat.

My old tank is 19gal and when it's full it throws the weight off bad being its installed on port side of the transom. I'm going to center this one for better distribution.

I was using this 19 & 22gal tanks in my comparison posted earlier. The 22gal tank you refer to is in a Larson Citation you're using as a comparible boat? Not the size tank you want to install in yours?

Its an 81 19.5' citation bowrider with mercruiser 120hp and MC-1 drive. i already have a nice 50gal. tank and it will fit perfectly between the stringers, minus the center stringer

You want to use a 50gal tank in yours?

That's a LOT of fuel, how often were you filling the 19gal you took out?

It's 2.5times the original capacity seems like a heck of a lot of weight to be moving forward. That's a weight difference of 186lbs when filled, which should change both the center of balance & buoyancy.

 

[GaJeff]

Re: Center stringer? Do I need it?

The only reason I want the 50 is because I already have it. If it wasn't for the cost of buying another tank I would rather put the 19 I have or upgrade to a 25ish. This boat sips fuel I burn around 6 gallons on a 3/4 throttle for a 8hr trip. Although that's not constant running its about 30-40mi.

Jeff

 

[GaJeff]

Re: Center stringer? Do I need it?

If I can get these pics to work ill show you what I got. I'm going to take my camera to the shop tomorrow as I think it's my iPhone that's causing the pic post problem.