stringer/bulkhead design

[friderday]

my son & I rebuilding 14' Ashcraft. Rotten stringers & transom. Just tabbed transom this week. So far things going smoothly. We are beginning to think about stringers design.The original design had 3 stringers; one in recessed keel that ran the length of boat, flanked by an 8' stringer approx 12" on either side of keel stringer. There were no bulkheads & the height of center/keel stringer was approx 6", the two other stringers 3". There is virtually no bilge in this boat, as the deck out toward the sides almost sat right on hull.We had originally thought to copy this design on our rebuild, adding a bulkhead at each 4' plywood deck joint, but my son posed an idea last nite. He thought we should get rid of center/keel stringer, using on 2 outer stringers instead, adding a couple xtra bulkheads. Any thoughts on this design?Can't think of any advantages, but then again, can't think of any disadvantages(can't think of anything/just want itching to stop; gotta love fiberglass).Will post pics of original hull before we tore out stringers, or what was left of them.

 

[iCam]

Re: stringer/bulkhead design

I am not a fiber guru, or even a structural engineer, but it seems to be that it would be a bad Idea to replace the keel stringer with bulkheads. Besides you are probably going to have just as much work and material either way. I would just stick to the Mfg. design (with maybe a bulkhead or two) and fill with pourable foam.

 

[tpenfield]

Re: stringer/bulkhead design

The v-hull is quite shallow on that boat, so there is not much strength in the outside stringers. A bulkhead may be good, but it will not replace the needed strength of the keel stringer.

So, maybe keep the keel stringer and add a bulkhead or two as desired. Make sure you have good access to the compartments below and provide drainage to the stern.

 

[Woodonglass]

Re: stringer/bulkhead design

The Stringers are absolutely necessary to give structural support to the hull. You should replace them as they were originally. If you want to add bulkheads that is your decision but IHMO not required. These older boats always have small bilge's. If you build her back the way she was she'll be fine and you'll have a structurally sound craft.

 

[friderday]

Re: stringer/bulkhead design

I agree completely with all of you. Many thanks & hope this will convince my son. By the way, I am his mom(age 50), not dad. What a great project we have embarked upon. Although itching every nite for the past 2 months, it is awesome how this has started to come together. Attached is few more pics of almost finished transom as of today. Will likely begin stringers this wknd. My son hasn't told me "I love you" since he was 5 & he will be 24 next wk, but when he needs a partner to grind, sand, or glass, it's not his dad. I am blessed. Thanks again for advice.

 

[friderday]

Re: stringer/bulkhead design

few more pics

 

[oops!]

Re: stringer/bulkhead design

hi....welcome to iboats.

fantastic that you and your son can do a project like that...just super.

as mentioned above it will give you no benefit to loose the stringer....just more work.

stringers are easy....

the reason your son wanted bulkheads at the 4 foot mark was so you can screw down the edges of the floor.

to do this.....you notch out the stringers at 4 feet and lay a strip of plywood down on the flat...then you can screw into the flat plywood.

you will need to bed the stringers on the hull....(put some goop down first so the wood is not directly on the hull)

we use either a construction glue called pl preimium. or a thickened fiberglass resin that we make our selves (its forum name is peanut butter).

click the link in my sig and use the index.....its all there.

also in the top of the forum is a sticky......it has links to good info.

there is a link there to a guy with lots of you tube vids on his build......good stuff.

this forum js the fastest moving and largest pleasurecraft information site on the net.
if you have something that you are not sure about.....post it here.

answers are usually no more than 1/2 hour away....(half hour is a long time here).

congrats on the project....the feeling he will get when he takes the boat out for the first time is super

cheers
oops

 

[Woodonglass]

Re: stringer/bulkhead design

The first link in my signature below has drawings and info on how to fabricate and install your Deck, Stringers and Transom. Baby Powder REALLY helps keep down the itch!! Really pour it on.

 

[Georgesalmon]

Re: stringer/bulkhead design

Go MOM! I like it.

 

[friderday]

Re: stringer/bulkhead design

Thanks to all for encouraging words. Oops-I have looked at your lengthy thread before. Very informative. Are you suggesting we not put in bulkheads & instead use the plywood strips on notched stringer? I saw pic of yours on page 22, post 547 of your thread. This would allow stringers to longitudinally do their job, while allowing floor to be braced with wider support I guess?And looks less labor intensive. Question-did you just let the outer edges of those cross frames rest on the hull or dab of PL or peanut butter & did you just wet them with resin to waterproof or CSM as well? You too, woodonglass. Very informative & much appreciated. Frisco Jay videos are great, aren't they? I regularly facebook him to keep him aware of our progress. Lastly, oops, I have become the peanut butter queen in this project. Kevin makes it crappy but mom makes it nice n thick. Also very good at the fillets on transom tabbing. If I keep doing such a good job, I'll bet he will let me continue to help, especially with grinding & sanding. (itch itch!!) You think it's bad, but the next day is worse when you work outside in 85 degree temps. Can't wait for summer. Argh!Let me know what you think oops. Waiting to hear back your advice before we work on final stringer plan.

 

[iCam]

Re: stringer/bulkhead design

ummm ..... I think I am in love... a woman that not only owns a boat, but knows how to fix it!!!! I think what did it is the way she said " mom makes it nice and thick...."

 

[friderday]

Re: stringer/bulkhead design

Here are some additional pics of transom work. Time to put all your advice to work & attack the stringers. The final tally on transom-2 pieces 3/4 plywood PL together, wetted out with 2 coats slow kick resin, then wrapped both sides & ends with csm, attatched to outer skin with PB, tabbed in 2 layers 1708, one layer woven on inside, followed by 1708 & csm each wrapped up & over & tabbed to sides. Whew! did we really do that?

 

[oops!]

Re: stringer/bulkhead design

nice job on the transom SM. (Super Mom)

uh......why did all the gellcoat come off the transom?

but thats ok........we can help you

 

[Woodonglass]

Re: stringer/bulkhead design

Yeah, and why did you fill in the cutout in the transom? Did the outboard not fit correctly? Did the boat's top cap have a splashwell? If so the cutout is necessary. Did you wrap the glass from the inside over the top and back onto the backside of the transom?

 

[friderday]

Re: stringer/bulkhead design

Thanks oops. This boat's original gelcoat was tragically painted over with 2 different paints. It is horrible what somebody tried to do pull off as a repair or restoration. We have already made several structural repairs to hull, both from inside & out. After demo, that was first thing we did. After patching from inside, we flipped hull & worked several cracks/small holes from outside. Then we gelcoated bottom & one side. We were about to gelcoat the other side when we discovered the transom we had thought was ok, was not. It wasn't terrible, by any means, but would have been silly not to replace after all other work. I was attempting to fill some of the many holes along rubrail before gelcoating final side. Former depth finder transducer holes on lower transom were kinda small to take filler. We drilled them out little & bit came out with wet, powdery wood shavings. And so, the gelcoat on one side has been put on hold for last few weeks as we gave it a new transom. The transom's outer skin was a trainwreck. Numerous small screw holes, & don't know why so many.Some had been poorly patched before. After transom was put in, I took to getting gelcoat off down far enough to expose all holes/inperfections so I could properly fill/repair as well as allowing a good wrap from other side far enough down to provide strength, & also feather out with csm. Haven't begun to final sand to prepare for gelcoat as we just finished last nite, but I must admit it looks great.A little sanding & it will be ready for gelcoat & good as new. Our repairs like this on outer hull came out so good we couldn't find seams. I will attach some more pics from early in hull repair. Hopefully, in your opinion, we haven't made too many mistakes. Like said before, it has been a pretty smooth restore so far. Timely & of course costly, but no real surprises. We have busy schedules with college(son) & work(both of us) so get to it when we can. We continue to take our time, ask for help, ignore the criticism, & listen to the good advice. You fall into the latter category. More soon.

 

[friderday]

Re: stringer/bulkhead design

Thought I'd throw in a couple fishing pics to show you what I do with free time when not huffing fiberglass dust.

 

[oops!]

Re: stringer/bulkhead design

to tell you the truth......i havent seen a mistake of any consequence.

as far as the fishing pics.........lol....are you a guide?

 

[friderday]

Re: stringer/bulkhead design

Thanks for the vote of confidence. Not a fishing guide, just love to fish. Fish every day off I get when not working on restore. Woodonglass-yeah the original transom was cutout. We didn't find that out until removing inner skin. To our surprise, these dummies made a poor attempt of making it taller by adding a friggin' 2" x 4" & lots of filler. **** poor job. My son has long shaft engine & wanted to keep taller transom. For the ocean fishing we do, the taller transom was also a good choice to keep waves from coming over transom on rougher days. No splash well. And yes; we were able last nite to do our final wrap of 1708 up & over AND tabbed again to sides, as well as finishing with a very forgiving layer of csm up & over. I didn't think we would be able to make the turn but it went off without a hitch, barring due diligence. I wish the pictures could do it the justice I see up close. So good it almost doesn't need sanding, but of course that will come.

 

[friderday]

Re: stringer/bulkhead design

Can't believe it's been a month since last post. Life took over for a while with work, family funerals, kids, etc.My son & I have worked as much as possible on the boat lately. Update-after transom, we did everything humanly possible to avoid the stringers. Don't know why, but neither of us quite knew how to start, nor had much confidence. I went to work on triangles at back corners that would eventually hold cleats & rear pole holders, besides giving stability to back/sides of boat. They were a pain for being so small. Made them out of 2 layers 5/8 ply, PB together, resined for waterproofing, csm top/bottom, installed w/PB, tabbed with 1708 top & bottom, finished with csm. They about killed me. In the meantime, my son worked up at bow had rotten wood as well as wood behind eye bolt. Once this was completed, we had no other choice but to tackle stringers. It took me 2 days to cut 2 stringers as the miter at stern was not as angled as toward mid/bow plus the curvature of boat upwards from stern to bow. What a nightmare, but it's done & don't want to relive it. I did it with persistence. He worked on center stringer while I worked on crossframes. Last week, stringers were PL'ed in & days later, glassed in with extra wide tabs 1708 to firm up hull. Couple of boo-boos, but nothing the sander/jigsaw can't fix. Need to sand tops of stringers as they have built up resin on from glassing in, prepare/waterproof crossframes, & get ready for deck.

 

[friderday]

Re: stringer/bulkhead design

Have one question-my son purposely wanted limber holes in back mini-bilge area. Notice on pics we cut out, then PB to waterproof, then cut out again limber holes in both side stringers where they meet transom. In addition, he wants drainage capability to both sides of center stringer just in case water gets below deck. Although we are pretty confident on our skills so far, we all know eventually water gets below deck & drains are a good idea. However, even though he will put a small bilge pump in this area (only 10" x 20"), he doesn't want water sloshing back up thru these holes into the forward bilge area. We're not sure how to block these off as they are not that big (for a traditional plug) & this rear bilge area is only about 3" at deepest area. Any suggestions on how to plug these other than my big toe or a rag? The piece at rear of center stringer is only template-not original nor glassed in until we figure this out. As always, thanks for help.