16' Marvac floor/stringer repair

[GT1000000]

Re: 16' Marvac floor/stringer repair

Morning,

I know exactly how you feel, went through all of the same emotions with my tub of mulch...

The only thing I can suggest is, think it through...

Yes, you could dump this off in little pieces for the trashman to haul away, save up your pennies and your courage and go in search of another boat, only to find that you have taken the same train to the same destination...

Unfortunately, old boats are just that, OLD! They also, usually come with the same problems...even Aluminum boats of bygone years have similar, although less problems...the wood is rotten and the foam is soaked and sometimes the aluminum has some problems like leaky rivets/seams or damage that needs re-welding or replacing, along with the inevitable re-building of the interior...

Then there are the motor issues...:facepalm:

In the end, the only sure way to get a great boat is to spend tons of dollars on tons of payments for tons of months, or have the luck of an angel and stumble upon that one in a million boat that has been taken really good care of, is in almost perfect working order, and is available for a miserly sum...

I decided to dive in, headfirst, and restore my tub of mulch, knowing that in the end, I would end up with a better than new hull, and a boat I would be proud to own and operate...my trade off for tons of monthly payments is months of sweat, itching, frustration, highs and lows, a decent amount of money [when available...], and other associated tribulations...which in the end is what makes this venture worth doing for myself...

Whatever you decide, we will back you up, whether it is for a full blown gut and restore, or a couple of sawzall blades and some quality cutting time...

And finally, thank you for the kind thoughts on this Thanksgiving holiday...even though you celebrated yours a month ago, may you and yours have a safe and enjoyable weekend...

Also, remember...that while all this restoration seems like a daunting task and while some have tried and given up, there are quite a few success stories that are inspiring, and with the incredible wealth of knowledge here, can be accomplished with some damned determination and a desire to conquer what seems insurmountable...

Best Regards,
GT1M

 

[saginawbayboater]

Re: 16' Marvac floor/stringer repair

It appears in the first photo in post 10 this builder started with a fiberglass hull, and built a splashwell and gunwale shelves and interior side walls out of fiberglass covered plywood. Then back filled with foam which would be a very safe boat.

If its all wet pull it all out carefully as to verify the plywood structure and maybe use the pieces for templates.

Reconstruct the Plywood structure and glass it in.

Don't forget to investigate the transom it maybe rotten as well.

Check out micks110 arkansas traveler he used sea cast for the stringers. That may be an option for you. The fiberglass on your stringers looks like maybe they would be a good candidate for sea cast.

 

[jbcurt00]

Re: 16' Marvac floor/stringer repair

Ye, what GT ^^ said...

Similar problems/concerns over this way:

Yep. Nobody eats an elephant all at once. Break it up into small projects that you can take 1 at a time.

Take a step back, consider your situation, and give it some time. After a few days, the OH CARP & the feelings of

may subsided & you can start to make a plan to finish the demo. At this point you own it, and it isn't going anywhere. And you are ahead if the exterior hull is in as good a shape as it appears & cleans up 'easily'

Task #1 will be to secure a good work environment, some safety gear & a grinder w/ some grinding disks & a shop vac. See steps 1A & B

From here:
Damaged Hull -- Pictures

We'll leave the garage lights on for you, dig around, see if you're willing to get this rig torn down & see what it'll take to get her seaworthy again....

As I don't recall if you mentioned it or not, what condition is the motor & trailer in? Another possibility is to use this hull as a learning experience, and dismantle it to learn more about a boat's basic construction. While keeping an eye out for another boat to use w/ your current motor & trailer. Using it as a learning experience, you'll be better able to know how, what & where to look for problem areas that should drive the asking price lower, or you to run back to the truck & walk away.

But like I said before, there is little down side to digging into this one, as it's in the driveway & you own it. It's good, bad & the wet foam too :redface:

 

[saginawbayboater]

Re: 16' Marvac floor/stringer repair

We'll leave the garage lights on for you, dig around, see if you're willing to get this rig torn down & see what it'll take to get her seaworthy again....

As I don't recall if you mentioned it or not, what condition is the motor & trailer in? Another possibility is to use this hull as a learning experience, and dismantle it to learn more about a boat's basic construction.

I second that JB

 

[100333624]

Re: 16' Marvac floor/stringer repair

Well I'll tell you guys what, it's nice to wake up to all these messages! I feel like I have an army at my back ready to fight with me! I had a nice long relaxing sleep and I'm gonna make myself a strong frappe and take a good look at my options..

GT: Your comments gave me some inspiration and I thank you for that! I restored an old beat up aluminum and that was my first experience, and what a nightmare it was! But the end result was worth every minute of frustration and trial and error put into it! Not to menion all the head this 12' aluminum turned! I figure the way this boat is now it can't get any worse, or can it??!! So at least I'll be working my way UP from down here...

JB: The motor is a 1978 Merc 80hp with power tilt/trim and she runs fantastic! She pushed this rotted water logged boat at about 38 mph with me and the previous owner in it! Just imagine what it'll do if it were all cleaned/beefed up! The trailer is also mint, with rollers and it can tow almost any boat 15-18ft.. What kills me is that I had a little aluminum boat that I had modified to the shiz with platform, carpet, livewell, aerator, trolling motor, swivel seats, fishfinder, storage compartments, 2 6" MTX speakers with a pioneer head unit etc... A nice control panel all nicely wired in... I put almost $2600 just in parts in it let alone all the hours I spent completely customizing it! And I loved that little boat and I traded her for this! That's what's killing me! Anywho, just from what I've done to it I've learnt a LOT about fiberglass boats so I know what to look for in the future that's for sure!

Saginawbayboater: Yeah it does look that way to me also.. But it's funny how they built it because the splash well isn't glassed in from underneath, it's all bare wood, and in pretty good condition mind you... The transom is solid, it doesn't budge and I took a hammer to it yesterday to remove the motor and trim bolts, it's solid! I guess they glassed it in seperately, then glassed in everything else... I am thinking about how to replace the ply back there in the gunwales but if I cut it from where it is I think I'd have problems as its all connected to the splash well and to the other side of the boat... To be honest it is only 4 pieces per side that need replacing its not much! Only one piece is "big" I just can't access it at the moment so I think if I can manage to pull the cap off I might be able to access it from behind? And I can replace it and glass it in there... Another thing I thought about is that it is pretty strong on the sides... What if I just removed the wood and foam and just replaced the foam and not the wood? Wouldn't the glass be strong enough as it is on the sides? Or would I be messing up the structural integrity of the boat now?

I found a guy about 2 hours away who's selling the exact same boat in what he says "GOOD" condition, with a 50hp Johnson in mint condition for $3900... But after seeing mine the way it is, I can tell you that his WILL have water damage as the cross braces they put by the drain area in the floor aren't even glassed in and the stringers are open there! All this boat really needs is a few monster waves or rain while towing it and what an invitation for water to come in!! Unless ofcourse the guys at Marvac built mine during a holiday where they were still wasted from the weekend

As for me, I put myself in this situation so I'm gonna try my best to fix it... At least if all else fails in the end I can't go down saying that I didn't try! My frappe awaits me, I'll keep y'all posted and thank you all for the support and insight into this! There is no "I" in team!!!

 

[100333624]

Re: 16' Marvac floor/stringer repair

Ok so I managed to rip the whole floor off so far and the livewell compartment and platform in the bow. I see glue marks running down from the sides under the gunwales where they fused the cap to the bottom hull, so the answer is NO the cap doesn't come off... It doesn't even budge... However, I do think if I cut off the splash well and the gunwales I could make them again from scratch? Why not? It's rotted anyway and I can make them better too.. But do I replace the flotation foam? I'd prefer to replace it anyway since it seems like it does a good job of stiffening the sides up a bit, and will float my boat just incase the inevitable happens...

I'm gonna come back tonight with lots of photos and ideas and I'd appreciate all you guys' insight into this.. Looks like there just might be some light at the end of this tunnel!

 

[jigngrub]

Re: 16' Marvac floor/stringer repair

I certainly would replace the floatation foam.

I can see cutting the splashwell off to access the transom and patching it back on, but I think there might be a better option than cutting the cap off at the gunwales.

I would cut round 8" diameter access holes in the interior sidewalls on 2' or 3' centers to dig the foam out and then patch them back. This would leave the boat mostly intact and stronger.

 

[100333624]

Re: 16' Marvac floor/stringer repair

I certainly would replace the floatation foam.

I can see cutting the splashwell off to access the transom and patching it back on, but I think there might be a better option than cutting the cap off at the gunwales.

I would cut round 8" diameter access holes in the interior sidewalls on 2' or 3' centers to dig the foam out and then patch them back. This would leave the boat mostly intact and stronger.

Good point and that is what I originally had in mind... But then that still leaves me with the soaked ply in there which is where the majority of the weight and water are! Replacing the foam isn't the problem, replacing the ply is... I think I'm gonna grind along the edges of those gunwales, grind them in nicely to the hull and peanut butter some new pieces on instead... The piece I removed from the gunwale is 7" x 15" out of 3/8 ply and 1/8 glass on top and weighs about 2 pounds.. I have a piece of 7.5" x 30" out of 1/2" ply that is about twice the size and 3 times lighter just by comparing them... Just imagine how soaked this stuff is..

I think I'm gonna redo them in 1/2" and the splashwell as well since I planned on modifying it anyways... More to come tonight with pics!

 

[100333624]

Re: 16' Marvac floor/stringer repair

Ok so this is what she looks like as of today, I ripped off all the floor and the livewell compartment up front.. I also found a little gift in the front of the center stringer, one of those drill chuck tools...


Anywho, the glass work looks pretty good in most areas other than where it delaminated from the stringers to the hull in a few spots....

 

[100333624]

Re: 16' Marvac floor/stringer repair

More delamination here

 

[100333624]

Re: 16' Marvac floor/stringer repair

I must have pulled out at least another 30 pounds or so worth of muck, and about 3 litres of water... That piece with the orange carpet was about 20 pounds on its own... There must be well over 100 pounds of water weight on this boat I can only imagine how fast it must be without all this excess...

 

[100333624]

Re: 16' Marvac floor/stringer repair

So I finally managed to get a bunch of guys together and got the motor off, and also finished building it's stand. What do you guys think??? How many stands have you guys seen with P/T lol


Ahhh my boat.... she's naked!

 

[saginawbayboater]

Re: 16' Marvac floor/stringer repair

Your making great progress!!!

 

[100333624]

Re: 16' Marvac floor/stringer repair

Your making great progress!!!

Thanks! Slow progress is better than no progress at all! I'm gonna cut the stringers and pull them out, and try to clean up the edges around that I've cut.. Possibly try to raise the boat so the floor hull drops down a bit... I might just raise it as it sits ontop of the trailer, like raise it above the trailer with blocks because I have no where to put the trailer... When I grind down the edges of the stringers and to clean out the unlaminated glass, do I use an angle grinder or an orbital sander? Like what is best to use to clean up and ready the hull for glass/resin? I'll also be needing materials in a few days so I'll ask y'all about that maybe next week..

 

[jigngrub]

Re: 16' Marvac floor/stringer repair

It's advisable to build a cradle for your boat before removing the stringers to hold the boat in shape, once you cut those stringers loose your boat will flex and sag (even while sitting on the trailer) and it'll be difficult to get the boat back into the specified shape and even harder to install the stringers properly.

Here's how Decker built his:

http://forums.iboats.com/boat-resto...-deck-stringer-replacement-help-471173-3.html

If you don't have a place to put the trailer or boat when off the trailer you can incorporate the trailer into the cradle, just add more props and braces to hold the boat in it's specified shape. Brace and pro up off of the garage floor and trailer frame.

 

[jbcurt00]

Re: 16' Marvac floor/stringer repair

I don't know what caused the problem, but it is quite likely that the hull sagged & is slightly askew:

http://forums.iboats.com/boat-restoration-building-hull-repair/total-rebuild-help-581353.html

 

[100333624]

Re: 16' Marvac floor/stringer repair

The hull has already sagged before I even touched the boat as the stringer in the center is rotted and broken glass around it, the rollers on my trailer are pushing the hull up like 3 inches.... So it already out of the question I need to support it somehow... As for the shape, I can measure the stringers and I left the floor edge around the boat where I cut so I can get it to proper height if that makes sense?

 

[jigngrub]

Re: 16' Marvac floor/stringer repair

Now is the time to get it pushed and propped back into shape, it's going to be even floppier and saggier when you cut those stringers loose.

Support your bow, keel, and transom first to get it pushed back into shape... and then under each stringer. Measure the width of the boat at the transom and then install braces from gunwale to gunwale to push or pull the gunwales to the correct dimension.

Use a long straight edge or line and gauge to get the gunwales flat (no sagging down or bowing up).

 

[100333624]

Re: 16' Marvac floor/stringer repair

Now is the time to get it pushed and propped back into shape, it's going to be even floppier and saggier when you cut those stringers loose.

Support your bow, keel, and transom first to get it pushed back into shape... and then under each stringer. Measure the width of the boat at the transom and then install braces from gunwale to gunwale to push or pull the gunwales to the correct dimension.

Use a long straight edge or line and gauge to get the gunwales flat (no sagging down or bowing up).

Ok that makes sense, but I have a question... My gunwales done even budge, actually the whole boat is pretty stiff, obviously except the floor. I can push and pull on the sides at the rub rails and the whole boat moves as one piece, stiff like a rock... Could this be because its a fused cap? Maybe it's just me but from what I see here in person, doesn't look like it needs any support on the sides, but maybe I'm wrong? I'm not saying that because I don't wanna go through the work to make them, I am saying that because it really is that strong.. The only thing flexing is just the floor. Makes me wish I had a digi cam so I can upload videos....

BTW, Deckers cradle looks awesome, but I can see why he would need one like that as his hull would be a bit flimsy without it right? I can definitely use one for the floor on mine... I wonder if I can put 2x4 going from gunwale to gunwale about every 2 feet going down the length of my floor right above the floor edge that I left from grinding the floor out, and screw these 2x4 pieces into the stringers that are on now before I cut them, with a 1" piece of spacing between the 2x4 and the stringers (5/8" ply + 1/8" glass, so that makes 3/4", + 1/4" that is the thickness of edge of the floor thats around the boat now) wouldn't this pull the hull up to its natural height? I can keep these in place till I make the cradle for it that way I'll have the perfect height? Do I even make any sense or did I just confuse the fish out of you?

 

[jigngrub]

Re: 16' Marvac floor/stringer repair

Yeah, your probably still is pretty strong with the fused hull, the Hugh Jass stringers, and the foamed sidewalls. Even though your stringers may be some what rotten, there's probably still a pretty good amount of weight in your saturated foam sidewalls... enough to deflect your hull when you cut those stringers free, and the fused cap is additional weight too.

When you cut those gunwales and stringers loose you're going to lose a lot of the strength you have now.

It's your boat and you can do it any way you want, I was just trying to help.