14r with Broken Ribs

[Crankworm]

Due to my wife's belly getting really big this summer I havn't been able to do much big water fishing this year, but on the bright side I have been using my 14' sea nymph at least once a week on some smaller lakes closer to home. The problem is the crappy roads around here have done a number. I now have 3 broken ribs just in front of the rear seat. I am in the process of putting wider bunks on the trailer and thinking about removing a leaf on each spring pack to soften the ride a little. does anyone know the best way to fix these ribs. Could I fix them without removing the whole rib from the boat, there are a ton of rivets holding them in. Thanks in advance.

 

[Howard]

I would say just get them tig welded. I had my done last week.

 

[Usmctanker]

x2 on the tig welding.
You could save yourself some money by cleaning up the metal before you take it to the shop.
If you have access to an angle grinder you could wire wheel all the paint and oxidation off of the area. By doing some of the prep yourself you can save money.

 

[bassboy1]

I'm gonna go against the grain, and say don't bother getting them welded. They'll only break again. Due to the fact that they broke the first time, they aren't adequate for the job at hand, and fixing them to the original state will just have them break again. They need to be improved upon.

 

[Crankworm]

Thanks for the input guys. There is a shop a mile or so from my house that should be able to weld it. Anyone got any idea how much it should cost? I'd hate to get gouged. As for the ribs not being up to task I will have to disagree Bobberboy. This poor boat is an engineering marvel I cannot believe it has held together for so long. I inherited it from my Grandparents 15 years ago, it stayed on the beach at their cottage on Lake Huron since before I can remember. My cousins and I have jumped 5' waves in it banged it into rocks and just generally beat the tar out of it when we were youngsters.

 

[bassboy1]

As for the ribs not being up to task I will have to disagree Bobberboy. This poor boat is an engineering marvel I cannot believe it has held together for so long. I inherited it from my Grandparents 15 years ago, it stayed on the beach at their cottage on Lake Huron since before I can remember. My cousins and I have jumped 5' waves in it banged it into rocks and just generally beat the tar out of it when we were youngsters.

My problem with it is the design of the ribs. Across the bottom of the boat the ribs are fine, as they are formed into the rounded hat section. However, at the end, where they broke, the hat section is flattened. Were I fabricating ribs that had to be of that design (flat at the end), I'd be cutting a pie shaped section out, and folding the pieces together, then welding the seam up. The stamped flat stretches the aluminum significantly, inherently weakening that end. Flat material, used in that configuration, is pretty weak to start with. Flat stock is excellent, provided it is used in a certain matter. The way it is there, it isn't adding much strength. In the first picture, is that a crack on either side of the middle rivet of the 3?

I'd say you'd be in just as good shape forgetting the flat piece at the end, and just putting a set of rivets at the end of the existing broken piece, to tie it the bottom of the boat. That last flat isn't gaining you much, but having the hat section fastened at it's end will unify the bottom of the boat.

Clearly, the boat wants to flex at that hull seam, as it broke multiple rivets. Either allow it flex, by leaving out the flat section at the end of the ribs (putting it back won't stop the boat from flexing, but the flexing will break the end again, just as it has there), or put enough structure in to unify both sides of the joint. It will take a structural shape, and I'd probably say have it run further up the sides, else having the piece end right past the joint will put a hard spot (not the right term, I'm sure - stiff structure that ends in a spot prone to flex, poking the end through the hull skin). Chances are, the boat doesn't need that, as the rest of the hull has held up fine through the years, so I'd say clean up the broken ends of the ribs, and fasten them solid, and not worry too much about welding them up. Main reason they are there was to clean up the end of the rib, and not have a sharp edge, and allow it to connect to the hull seam rivets.

 

[perchin]

Sorry bassboy1...... but I have that exact boat, and it doesn't do much flexing. Mine is very old, has the same design and no cracks. I doubt Sea Nymph would of kept this design for 15 years if they all just fell apart. Repair em' and don't run an outboard over the 15hp rating, and I would bet a paycheck you'll be fine.

 

[Usmctanker]

I had several "random" rivets in the bottom of my boat and I went and got them welded up. I called ahead and made sure the guy was already set up for aluminum and he only charged me 15 bucks. Call ahead and if the shop is already working on aluminum it will be cheaper since you don't pay for the labor time of switching over the leads and all that, just the welding. Most shops around here (Oklahoma) charge $40/Hr.

 

[crazymanme2]

When I weld aluminum boats I try to stay away from the seams.I would drill out the rivets & re-rivet a new piece in & weld it aways back from the seam.The boat is old & I'm sure its seen some abuse.Its not a design flaw.

 

[Howard]

I would say strength is in numbers. If all your ribs are broke then you have a engineering issue. If one or two broke then it is just simply wear and tear. If you plan on jumping more 5 foot waves :shock: then beef it up . Prices for welding around here is around $60 - $ 90 an hour. Some welders are faster then others which plays a key in pricing. I had a 6" tear in my tin where the side wall and hull met. One welder said $60 an hour and would take about 1 1/2 hours. ( $90 ) Drop off Monday and will have it by Friday. Brought it to another welder and he said $90 hour. He said pull it in the shop now and I will be done in 1/2 hour ( $45 ). He got the job and subsequently I had the rest of my welding issue taken care of while I was there. Do the prep work before going and they are more likely to take you then and it will keep the cost down.

 

[bassboy1]

Sorry bassboy1...... but I have that exact boat, and it doesn't do much flexing.

It isn't flexing due to weakness, it is flexing due to being designed to flex a little bit. I haven't ever worked on a riveted v hull in my life that hasn't had even a little bit of flex. It would flex a little bit when new, and 30 years later, it would flex that same little bit. To build a boat that has no flex, you are looking at serious material, and a boat of different design altogether, and probably not riveted, either. Those boats have to be strong enough to withstand everything they hit, as they cannot "absorb" the hit (I'm talking waves, bumps on the trailer - not necessarily rocks). They exist, but they are primarily 1/4" hulled welded aluminum rigs in the 20+ ft. range. If you allow the boat to flex a little bit, it is able to absorb those hits, and suddenly you are capable of making a hull a lot lighter, and as such, you see all the smaller tinnies we all have. Aircraft are the same way. They move all over during flight, and while I can't speak for the newest of new ones, all the rest of them are constructed very similarly to these smaller semi vees, which is due mostly to all the aircraft companies switching their work over to building small recreational boats after WWII.

I'm not necessarily saying that the boat flexing is a design flaw. What I am saying is that it is proven the boat flexed - the piece wouldn't have broken if it didn't, and that the boat is always gonna flex. A few years back, I had the 12' version of that boat, designed and built in a near identical manner (and in 'new' condition - I put the first scratch it ever had on it), and yes, it flexed. Not near as much as the '50s era Larson I had at the same time (would flex all to heck and back, due to getting old, and having worked everything a little looser), but it was there.

If you had the rib off the boat, (and clamped to something to keep the hat section from spreading open, just as the rivets on the boat hold it), chances are it would take a little bit of effort to bend the hat section with both hands. But, the flat section could easily be bent with just two fingers. My point is that it isn't doing much good being there, and clearly (as evident by the fact that they broke), can't withstand the inherent flexing the boat obviously has (as evident by the fact that they broke).

Welding those back up in the position they are in is not a good option. To weld it properly would involve pulling the rib out of the boat, as Crazymanme mentioned, and probably starting with at least some new material. However, due to the fact that these boats have worked for years and years for many people (myself included), with the flat section at the end of the rib, I see that the flat section is not a structural piece (in the manner it is being used in, I can't see much strength being added), and is instead there to 'clean up' the end of the hat section, so crap can't find it's way down in there, and no sharp edges are left exposed.

 

[perchin]

Bassboy1..... I agree with you and always enjoy your input. I just meant I don't think it was a design flaw. What you quoted me saying says it best. I didn't say it does not flex, just not much.

 

[Crankworm]

Thanks for the input everyone. Like I said before the problem is from trailering on messed up crappy roads not how I use the boat. My back is to old nowadays to jump waves. The guys from Michigan can vouch for roads I'm talking about you couldn't believe it unless you see them for yourself. I took a short leaf out of each side of the trailer springs yesterday and took it out this morning. that did the trick, it goes down the road much better and the suspension seems to take up the bumps without jolting the boat. I will try to get it cleaned up and into a welder to fix the damage done.
Perchin I believe your boat is a 14m mine is a 14r with higher sides and a 24 horsepower rating. Thanks all for the help this board is awesome. I will post some pics once it is fixed.