Lund Nisswa Restoration

[lundnisswa]

I am removing EVERY speck of rotted wood from this boat. And Removing water logged foam.
The Transom seems solid, the middle 6' of the center stringers were rotten, I have started on the two center stringers and will do the two outboard stringers next.
My First Question is; I want to use one continous piece of lumber for the stringer, they are 14' long, my intention was to plane a 2x10 to 1" thickness, waterproof with CPES after cutting to fit, I have left about 1 inch of the original fiberglass channel sticking up out of the floor and have cleaned it out (still have more sanding/grinding to do), will clean it up one last time with acetone prior to my plan of using epoxy/sawdust slurry to glue it in the channel, then I was going to dress up the fillet, then proceed to glass in three layers with 2" overlaps up the sides.

Is this a sound plan?
What is my best option for a 14' stringer as far as wood goes?

Scott R.
"Its Not How Deep you Fish, It's How you Wiggle your Worm"

 

[lundnisswa]

Re: Lund Nisswa Restoration

Here are some Pix of progress so far

 

[lundnisswa]

Re: Lund Nisswa Restoration

Have owned this boat since 1988, it is a 1986 Lund Nisswa 16.5 fishing machine. A few years back (8 years) the floor started getting mushy under the seats so after a quick evaluation I decided to put a temporary floor over the bad stuff, what a mistake that turned out to be, it just propagated the rotting.
So I decided to fix the rotting floor this year but had no idea what I was getting myself into, the floor literally crumbled, I bet I have pulled out 500 lbs of rotten wet wood and water saturated foam.
The more I dig the more I find, last night it took me 6 hours to dig the wet foam and rotted wood out from under the Starboard side.

A few questions for you guys,
The boat is supported on an 8' bunk trailer, do I dare pull all the stringers at once so I can get in there with an air sander and start cleaning it up?

I am going to take the advice of a fellow member here and use laminated Ply for the stringers, and not use 2x10's as I had originally planned, I will laminate/sister the ply to length and water proof all edges after cutting to fit with either CPES or thinned epoxy.

Here is one big decision I am trying to make, should I grind off those channels and epoxy directly to the floor?

I have a ton of work to do yet but it is actually a great passtime.

Oh, the one tool I did not have was the Roto-Zip, I have it now and that tool is amazing for cutting fiberglass or anything for that matter in tight spaces, it is like a dremel on steroids.

I will take any and all advice you guys give.
Scott R. in North Dakota

 

[erikgreen]

Re: Lund Nisswa Restoration

On a bunk trailer you should be ok removing both stringers at once.... almost all bunk trailers seem to give nice even support to the hull.

Good luck and keep going

Erik

 

[sladers]

Re: Lund Nisswa Restoration

Whoa...I know where your at. I've just started a thread about my deck and stringer project. Check it out

http://forums.iboats.com/showthread.php?p=1602266#post1602266

I was wondering if you could explain to me what the term "fillet" means. I've read it in a couple of threads and haven't been able to figure it out.

Thanks

 

[oops!]

Re: Lund Nisswa Restoration

hi lund
welcome aboard....

good proj.....

i agree totally with erik....you wont have any problems with leaving it on... it will be a good working platform...and makes it easeyer to move.

i would get rid of thoes channels and bed the new stringers with cabosil and chopped strand.

just glass in the new stringers with a matt cloth matt type layup.

yer doin good....keep atter

cheers
oops

 

[oops!]

Re: Lund Nisswa Restoration

oh ...and btw....

i would use dry pressure treated ply wood....that stuff can lay in water for twenty years and still not rot


and sladers.....

a fillet is a type of fish burger at mc donalds..

cheers
oops

 

[lundnisswa]

Re: Lund Nisswa Restoration

Well I am not nearly qualified to define terms related to fiberglassing but my understanding through all the reading I have done is that fiberglass when layed up does not like to take sharp turns, you get wrinkles and air bubbles which are both bad in the fiberglass world, so where ever you have sharp angles to fiberglass, such in the case of where the new stringer meets the hull, you fill that area with a thickened mixture of resin/thickener to make a smooth transition.
Well thats my understanding of a fillet, and I am sticking to it!
No Pun Intended..................
Scott R.

 

[lundnisswa]

Re: Lund Nisswa Restoration

Erik and Oops thanks for chiming in.
I went and checked on Pt ply today, it is PT6/ACQ treated, but all that I looked at is so wet and slimey it would take forever to dry, I am currently chasing down prices on Marine grade ply too.
Today I am digging out under the port side where the floor goes under the rod/storage lockers.
My next major step is to pull the engine and inspect the transom really good, luckily I have easy access in this boat to the inside of the transom, more to come on that.


Yes the bunk trailer does seem to support the boat very well and it sure is nice to be able to move the outfit, pulling the boat out of the shop on a warm windy day makes the dust so much more manageable.
So you guys concur that it "should" be ok to pull the other two stringers, I will have all 4 stringers out at the same time.

Scott

 

[ondarvr]

Re: Lund Nisswa Restoration

It's hard to say if it will move or not, not all bunk trailers support the hull in the correct way to have no flex when the stringers are removed, plus some hulls are thicker (stiffer) than others.

While it's still on the trailer you can use jack stands or blocks of wood to support the transom and under the keel towards the bow, this will help keep everything in line when you glass in the stringers. For grinding you don't need to support it, you just need to line everything back up before glassing. When everything has been removed walk around in the hull and see how much it flexes.

 

[lundnisswa]

Re: Lund Nisswa Restoration

Well the Port side inner stringer was in my way of cleaning out the last of the foam and flooring from under the rod locker so I cut it off with the Sawz-All, this stringer was in the best shape of all of them, interesting to see just how WET that wood really was on the inside, just a matter of time and that sucker was dust too, so I am happy I decided to replace ALL of the them, do it once/do it right is my goal.

So I got all of that foam out from under the rod locker area with alot of digging, and when it came time to pry out the piece of floor under there it actually came out in one piece, that is the first piece of floor that did not crumble when I apply any force to it, my immense body weight must have kept more water on the drivers side, or maybe that huge fish I am usually holding-LOL-anyway.

Back to the Plywood, turns out that I cannot purchase Marine Grade Plywood in Northwest N.D. unless I buy the whole bundle and have it shipped, must not be cost effective for the covered wagons to haul a load to "Dem Der Parts".
My dad says to check out AA Ext Plywood if I am not willing to wait for the slime to dry from PT, still trying to find some dryer PT around here.

Done for the day, off to work.

Scott R.

 

[lundnisswa]

Re: Lund Nisswa Restoration

OK, got the rest of the stringers removed from the channels this morning,
Speaking of the channels, Why have I convinced myself that leaving some of the channel sticking up out of the floor is a mechanically good idea, lets say maybe a 1/2". I see the consensus from you experts is to grind her down to the floor so I have a clean new surface to adhere to, but I sure was thinking that if I cleaned em up real good it sure would be a nice guide to bed-in the cut to fit stringers, the filler (Epoxy/cabosil) would just ooze up out of there and then glass her in.
Now what is the reason for the 1/4" foam cushion under the stringers that I dug out? Well in all the reading I have done it states that no part of the stringer actually should touch the hull, I guess it can cause stress cracks, So along those same lines it reinforces my idea in "My Head" of leaving that channel, pretty hard to epoxy something to the floor when it is sitting on a foam cushion strip?.
I have been monitoring the exterior hull condition as I have been removing the stringers, I can see no change in the hull so far, when I walk in the boat toward the sides there is some flex but not much, seems to be supported pretty well.
OK, once again I need and want all advice you and others have to give because I am a novice at this. I am all but done digging out all bad wood.

Still have to put a critical eye on the transom this week.

I havent even ordered the glassing supplies yet because I am trying to get the kind of knowledge base here before ordering so I dont get the wrong stuff. (I have read more threads on here than you can imagine, and my head spins because every one seems to do things just a bit differently.
I understand Matt/fabric/Matt, but what weight and type would you recommend? Is all epoxy resin created equal? Is 3 gallons enough? Is cabosil the filler of choice?

When I go to glass the stringers in is this the general idea, Successive layers draping over the top, getting wider upon each layer, and the less seams the better. So if this is a 12' stringer, that at its tallest point is 10", first piece of cloth would be about 14" wide, would you do the entire 12' at once? Let that cure do another and so on, or lay up all three layers back to back for a good chemical bond, immediately after nesting the stringer to the floor and then drape 14" -18" -22" .....

Rambled on again didn't I.
Scott R.

 

[fixb52s]

Re: Lund Nisswa Restoration

I am doing just what you are talking about. I have the stringers out and new ones cut. I also am leaving a "channel" because I had the same concerns as you. I have cleaned them up as well as I can. I talked to a few boat builders here in Tampa and they agreed that this is a sound idea.

You get so many opinions on this board. One person says yes, the other says no. (Like keeping it on the trailer.) Do what you think is right.​

 

[lundnisswa]

Re: Lund Nisswa Restoration

Fix B-52's, this is too ironic!
I worked B-52's for the last 10 years and spent the previous 16 years on other Mil Aircraft.
I sure hope you know how to work with fiberglass better than I because this is all new territory for me, I could use one of those FAb guys that used to come out and fix the old buff when we banged her up, about now.
Anyway, if you want to shoot me an e-mail maybe we can work out some problems we are having without plugging up this forum too much.
Lundnisswa@aol.com
Scott R. in North Dakota

 

[Coors]

Re: Lund Nisswa Restoration

search ondarvr threads.
Epoxy sticks to anything, just keep going 2" wider overlap (when you stated 12", I think you forgot to add in over the top of the stringer. If possible, keep applying before the last layer kicks- chemical bond.
Pre-cut the material, and spend a day. If you use slow hardener, breaks are allowed.

 

[lundnisswa]

Re: Lund Nisswa Restoration

OK, on to the dreaded Transom.
I have included a few photos, there is a one sq foot area that is starting to rot and the rest of the wood on the Transom is in amazingly good shape, you can even see the wood grain, looks like oak, I took a drill bit up in higher spots where screw holes are and got nice dry wood too.
The one picture that has the plastic drain tube sticking through that has the over sized hole has started to get soft inside there, inner ply.

So my question; is there a technique just to fix just the bad portion, can I chisel down to good wood in this one square foot area and then use something to build it back up to level?
Thanks
scott

 

[lundnisswa]

Re: Lund Nisswa Restoration

I want to get this splash well drain (aluminum insert) out so I can look at the core of the wood up high in the Transom, it is flare crimped both exterior and interior, I know I can just destroy it to get it out but is there a better way?
And can I find a similar product for the splash well drain holes to replace it?
Scott R.

 

[lundnisswa]

Re: Lund Nisswa Restoration

OH NO! There was a 6 foot piece of fiberglass/wood that runs length wise with the keel and that was there to support the fuel tank. This was the last piece I wanted to take out of boat because I was using it as a walking surface, I knew the wood was soaked, I pulled it out and it may have a revealed a show stopper, need you opinion on this.
**The keel exterior keel had been rubbing on a metal crossmember of the trailer, when I rebuilt the trailer 5 years ago I adjusted the bunks so the trailer no longer touched/rubbed the area, I had since put a full length keel guard on there.
ANyway, on the interior of the boat this spot is flexible/loose/delaminated/bad or whatever you want to call it, about 2" long x 1" wide loose area.
See pictures; can I recover from this??????
Scott R.

 

[oops!]

Re: Lund Nisswa Restoration

lund....

i cut my boat in half.....

people have stretched......widened .....built up ...and done all kinds of crazy stuff with boats......you can fix anything......

can you please crawl under there and give a pick of the exterior hull in that area?.......

i dont think its a really big deal......ive seen glass boats that have the keel litterally cut out of them...stem to stern......

on the west coast.....i saw boat yards with aluminimum hulls that were dissassembled.....whole sections....... gone....and the boat fixed in a short while......rest easy.....its just a little more work

 

[oops!]

Re: Lund Nisswa Restoration

also in post # 18 thumbnail #1 there is what looks like exposed glass..(the white hary area) .can you show us a pic of that area?.....


ill be on the road all day today....then back on late tonight......mabe coors and the guys can help gide you....and coors also said "read ondarvrs posts"....read them all.....twice..!.......he is the don-s of the fiberglass world.

but again ...relax.....anything can be fixed

cheers
oops