water behind a stringer

Not sure how this forum thing works, so bear with me here gang.
I have a 72 Ski Nautique. I know the stringers have only dust inside at this point.
I am familiar with fiberglass work primarily from my old Navy days repairing the fiberglass small boats on my ship.
Why can't I cut the top of my stringers off and use the existing skeleton as the form to lay up and strengthen the glass that is what's left of the old stringers? I'm not talkin' filling the box full, but forming a new thicker, stronger box. No wood no rot.
I know you may tell me where to go, but I would like to learn more about the error of my thinking.
I appreciate words of wisdom, random opinion and links to information.
Thanks!

Randy,
If you feel comfortable with calculating out the modulus of material flexure between the original Doug Fir and the epoxy/glass to give you the needed equivalent, I encourage you to move forward.

The Doug Fir is the "tried and true" plus with careful sealing with CPES (clear penetrating epoxy sealer) and then epoxy/glass it will be there I'd say 5 to 10 times as long as the factory job. The factory jobs at best were on the sloppy side and used the polyester resin which is hygroscopic. (epoxy isn't!) Plus, they made no efforts to seal attachment holes into the wood with a excellent sealer like 3M 5200. Joe (JoeinNY) is a good example and the only one I know of here that built "outside the box"!!

Even though I could run through the modulus calculations, I'd still stick with the wood. Must be the wood boat person in me!!!!

Welcome to the site if you just found us or even if you've be around for awhile and just started to post.

How about some pictures and some more info on the boat. Have you had it for awhile? Which engine? Original?

I got a bunch of mostly fun little stuff done this weekend. After Wednesday I am off the boat for 10 days. Going to my cabin in North Idaho for a few days of fun winter stuff and then headed to Astor to hang with all the CCFan's for a nice weekend on the water.

I have my kickboard all cut, epoxied, drilled out and carpeted. Heater is installed, bilge pump installed, stereo stuff run. the windshield, as much as I hate it, is back on, and a few other miscellaneous projects done.

Firstly, this next photo is for the Boat Nurse as she gave me a hard time about the crappy return spring I had on the engine after reinstalling: You were right, Karen!



Next is the engine with the heater hoses hooked up, and the cables rerouted behind the pulleys.



Lastly, the new dash with the windshield re-installed. Sans steering wheel and helm.



That is about it until mid Feb when I get back. Then I will have all my new exhaust parts, get that in. put down the floor, carpet the floor, and finish this God-forsaken project finally. My last official act will be to hang a new flag.

I am currently at 248 hours and about 410 beers.

Mike,   mountainbound, then sunshinebound !

mike, that is 1.8 beers an hour...not bad

really 248 hours? at 50.00 per hour hour at 12k....without materials lol

Thanks to all for your responses regarding stringer alternatives.
I don't mean to take away from the Wake Slayer's project/progress evolution. Great work by the way. Heavy on the "work" part.
Clearly, I have no references for calculating the flex modulus of a "ho" made stringer. Maybe it would be too flexible or a nice hot mixture of resin is too brittle for the job.
In any case, the boat will stay in the garage when not on the lake.
The prop shaft alignment appears to be very good, however, I'm nervous about the strength of the motor mounts bolted to hollow stringers. Probably the only reason I worry about the strings at all.
What other bad thing can happen beside gross engine missalignment if the stringers are bad?
Thanks again for all the feedback.

Talked with a guy at a long time correct craft dealer today who had used seacast and was a big fan of it. He had a left over chunk of it and it was hard as a brick. I definitely think it would hold up. He said he used a bucket and a half on a tique a while back. He thought 2 buckets would get it for a nautique.

Im still going the traditional route, but just some food for thought since there was some conversation about stringer alternatives.

Lewy figured the weight of seacast spmewhere in the pumpkin patch...heavy!

8122pbrainard wrote: Greg, Have you been taking spelling lessons from Chris?

2 points

Someone should be watching our gov't so closely...

And we should know tomorrow if I need the Atom for a parts barge.   

8122pbrainard wrote: From what I hear, it sounds like you have got it figured out!! I really admire your perseverance!

Perserverance in this case is spelled A-M-Y, and she wants to go for a boat ride!   LOL

And what have yall been feeding to the grapevine?!!?      

jbear wrote: ps: Don't you ever answer your phone?

Try this # 770-536-2328

Randy,
Before you even start ripping things out, begin measuring the existing. Measure every time you open up a new section of floor. Figure there's about 1/8" of glass on the wood. The most critical dimensions will be the main stringers around the engine. Mark the hull sides with reference height elevations. Cut the stingers over width and scribe/cut them to the shape of the hull. Oh, take plenty of pictures as you are tearing out!!

eric lavine wrote: mike, that is 1.8 beers an hour...not bad really 248 hours? at 50.00 per hour hour at 12k....without materials lol

Just got back from vaca in the mountains.

Serenity !!

Umm, yeah, 248 hours. And I was thinking I would bill higher than $50 per hour.... Seems completely ridiculous, but what else am I going to do during the winter....

Leaving for Astor Thursday. One extreme to the other.

72 ski antique wrote: Pete, Please tell me more about "Cut the stingers over width". Do you mean make the new ones wider than the old? I think I can handle the scribe process. Perhaps that's what you meant when you said over width.!? Room to take away and end up the right height and width? Let me know. Randy Combs

Randy, Yes, I think you have got it! I said "width" of the stringer which is really the height as it sits in the boat. The extra is for what you will scribe and then cut off the bottom to match the angle and curvature of the hull.

72 ski antique wrote: Thanks Pete. How sbout the wood? Certainly not some #2 white pine 2x8 filled with knots! Any particular sources? Besides the forest....

We're lucky here in the upper midwest than it's still relatively easy to find Doug Fir. However, not in the lesser widths (2x8? and 2x6). You may end up having to get a 2x12 and make two stringers from it. A few small solid tight knots in the center of a stringer won't hurt anything.

Edit: For tose in areas where Doug Fir isn't readily available, I just thought of a decent alternate: LVL Microlam! Available in 5.5, 7.25, 9.25, and larger widths. They are however 1.75" thick. Lots of CPES on the edges and it would make great stringers. Not that much heavier ether.

TRBenj wrote: Pete, Ive played with microlams back when I worked construction. From what I remember, that stuff was HARD! I would think it would be a bear to shape, no?

Tim,
They really aren't that bad because they are made from Doug Fir veneer. It really thick plywood! Slightly harder only because of the glue used. Now, whether you're cutting out stringers from plain 2x's or microlams, a decent band saw and a hand held power planer does come in handy.

With the difficulty getting Doug Fir in some areas, plus the junk we are seeing lately called "lumber", I'm really surprised that I as well as others haven't though of it before. It's really a decent product. I don't know how much more the expense would be.