Correcting a hook?

Neal Haarberg

Neal Haarberg

Active member
I have turned an old fiberglass boat in a sneakbox and took it out for the first time yesterday. There was a bit of a hook in the fiberglass hull back by the transom from sitting on the trailer bunks for so many years and it caused the bow to go down when I get up to speed. I have the motor trimmed out all the way but it did not help. I expected it to happen a little but it is more severe than I would like. Is my only option to fill the hook with something? If so then what? I'll try and get some pictures up later.
 
I have turned an old fiberglass boat in a sneakbox and took it out for the first time yesterday. There was a bit of a hook in the fiberglass hull back by the transom from sitting on the trailer bunks for so many years and it caused the bow to go down when I get up to speed. I have the motor trimmed out all the way but it did not help. I expected it to happen a little but it is more severe than I would like. Is my only option to fill the hook with something? If so then what? I'll try and get some pictures up later.
Click to expand...


Yes, it can be done. My concern is that if the hull sagged enough to hook that there would be enough flex running and trailering to pop the filler out. You may need something to stiffen it longitudinally to correct the hook or at least hold the hull stiff enough to hold the filler. Adding someitng to stiffen is easier said than done, because any time you add something to stiffen a hull (especially a flexy one), you run the risk of making a hard spot that will tear at the junction of the stiff and flexible parts. I am no expert, but I woudl think pictures woudl help tell your story.

T
 
If it is truly warped from sitting on the trailer, you'll have to brace it out and apply a layer of glass to the outside to hold the original contour, then fair it to smooth it. Some FG hulls were made with a hook at the transom intentionally. It was more popular in the past than now. It acts like a built in trim tab. If that is the case, you'll have to fill it to make it fair from the middle station to the transom. You can use epoxy with microballoons and just enough wood flour to thicken it or you can just buy QuickFair. I recommend bateau.com for the supplies, but even if you find the supplies cheaper elsewhere, Bateau's forum has the best how-to information.

Nate
 
Years ago I had a similar problem.A gentleman I knew ,who was boat smart,told me to
raise the motor around an inch to an inch and a quarter.I did that and it changed
everything for the better.Easy to do and worth a try before you start buying things.
 
From experience, the extra layer of glass will have enough give to be ineffective. Epoxy and fiberglass both "stretch" enough especially on gentle curves, that if the boat's shape has memory from being trailered a specific way or having hook built into it from the start, then the glass will merely follow that shape when released from whatever shoe stretcher like mechanism is utilized.
I was asked to fix a problem like this once. My customer wanted a fiberglass skiff similar to one he was fond of in his youth to be completely restored. I was skeptical as I knew this would be quite an endeavor, but he wasn't concerned about time and money so, I stripped the floor system out and put two of my large wooden topped work tables together and literally screwed the hull down to the benches to keep her where i wanted her until a newmarine grade ply "egg crate styled floor system complete with glass tabbing to the hull could be put in place. I was mostly successful with correcting the shape of the hull. A little spring back was still noticed when seperated from the bench. It was a time consuming process. Keep in mind this particular project was definitley suffering from hogging even if it had been constructed to have a bit of hook, i.e. it looked bad. This was a very time consuming project considering the end product.
I really like the idea of raising the motor as a quick and easy solution for decreasing the lift from the transom. Good luck.
Frank
Middletonboatworks.net
 
Neal,

You are most likely correct in that the hook developed from improper bunk placement under the boat. This usually develops over many years. I think you are on the right track to use a filler to bring the outside surface of the hull back up to the shape needed. The thing I would suggest is a layer of fiberglass across the entire hull after you are have added the filler and faired everything out.

What you will end up with is a cored construction which will be much stiffer than the original hull. The sandwich will be (a) first layer=the original glass (b) core=the filler material used to fill the hook (c) outside layer=the new glass layed over the entire hull

With out the new layer of glass on the outside, I would tend to agree with Todd's assessment of too much flex to hold the filler, if filler alone is used.
 
I had a customer with a 1959 Speedliner that had four areas that the rollers indented the bottom. After prepping the dented areas I filled them with thickened epoxy resin. Faired them and finish coated the bottom. The boat now runs graet. If you are concerned about the filler popping out I would put one layer of fiberglass over the repaired areas to hold the filler in. I don't think that you need to do anything from the inside of the hull. Keep it simple.
 
I figured the answer would be fill with thickened epoxy and glass over it to keep it in due to the hull flexing. I did put longitudinal supports in the floor. The original construction had a wood core fiberglass sandwich. We had to remove all of the wood because it was totally rotted. After removing the old wood we put a couple layers of glass down then floor supports and then a plywood floor. It's pretty solid now and a neat little boat. Once I get this hook problem fixed It will need to be wired up with lights and a bilge then It will be ready for the BLuebills!!!!
 
You must log in or register to reply here.
Back
Top