# Johnsen Boat Flex



## costefishnt (Dec 11, 2006)

This is normal. Think of it as a built in shock absorber. Unless you see MAJOR stress cracks from said flexing you are fine. 

Stress cracks= Deep noticeable by look and touch.


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## snooknreds2 (May 5, 2008)

> This is normal. Think of it as a built in shock absorber. Unless you see MAJOR stress cracks from said flexing you are fine.
> 
> Stress cracks= Deep noticeable by look and touch.



keep your eye on small stress cracks near the transom though...they could mean trouble


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## Ram5773 (Mar 20, 2008)

No cracks near the transom, darn thing is a 1 3/4 thick. Glad to hear it's normal although it doesn't look normal, bounces my cooler up and down like shaking a mixed drink at speed. 

Any thoughts on the repair side of fixing the cracks or just monitor them and see if they get worse??


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## backwaterbandits (Dec 15, 2006)

Those Johnsen boats are a VERY popular skiff design!
A lot of folks around here keep an eye out for one of 
several models that were made over the years...I'm
not sure of the last year of production...but it's been 
a while now.
It is common to see cracks repaired on these boats,
but I've not heard of a hull failure.


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## Ram5773 (Mar 20, 2008)

The main reason behind this is this boat was a daddy daughter build and if she is on it I want it to be safe, the flex really threw me for a loop the first time I saw it happen


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## Jacbo (Jun 23, 2007)

My first real boat was a johnsen knock-off. It didn't flex bad when I had a 10 hp honda on it, but when I put my 35hp johnson on it, the flex got so bad that the back seat developed two cracks over a foot long. The problem with my old boat was that It had no stringers. If I knew what I know now I would have glassed in some stringers, built a floor and decked that sucker out. ;D


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## Ram5773 (Mar 20, 2008)

Jacbo, how quick was that boat with a 35? Mine Gps at 29.6 with a 25hp and gear

I think I'm going use it for a while, sell it and upgrade to something nicer

Thanks for your replies


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## Un-shore (Sep 27, 2007)

I have a boat of similar design. The floor might be a sandwich with plywood. water may intrude through the stress cracks and rot the plywood. This may of happened already and might be the culprit of excessive flex. I can see a hint of a keel in the pictures, is that the case? is the floor the same contour as the bottom or are there two chines on the bottom?


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## Jacbo (Jun 23, 2007)

Back when I had that boat I didn't have a gps, but I remember it to be pretty dang fast. I would guess around 35.


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## snooknreds2 (May 5, 2008)

> The main reason behind this is this boat was a daddy daughter build and if she is on it I want it to be safe, the flex really threw me for a loop the first time I saw it happen



when you say daddy daughter build....what did you guys build on it?




> The problem with my old boat was that It had no stringers. If I knew what I know now I would have glassed in some stringers, built a floor and decked that sucker out. ;D


i was thinking the same thing. Although some flex is normal it sounds like he has ALLOT of flex in fact he said it "shakes my cooler like mixing a drink". I have never been in one of those boats but that sounds like allot of flex to me. 

i would check to see if there is water intrusion in to the plywood sandwhich (if that is how the boat is constructed) From there excess the situation. But I would think some stringers and a false floor are going to be in the near future


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## Ram5773 (Mar 20, 2008)

Unshore, there is just one down the center like a spine about 2in tall. you are correct in saying the floor resembles the bottom of the boat. on the far outside of each side of the boat there are I guess reverse chines?? like air pockets that starts when the hull flattens out. Some rocket scientist who owned the boat before me drilled a couple of small holes through the bottom of the dry storage area's. When I was repairing those holes I didn't see any wood? I think it's just thin fiberglass. I wish I knew someone that had one of these boats that I could speak too.


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## costefishnt (Dec 11, 2006)

My brother had one. It is fiberglass bottom. The flex is normal. You should see a highsider gheenoe with no false floors and a 25h merc. Wanna talk about flexing.

The flex is normal. When you are not used to it, yes it looks scary. There are not many micro skiffs out there with no flex... It is inherent as if they had made the floors so stiff that it didnt flex you would have your brains and kidneys shaken from your body.


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## Ram5773 (Mar 20, 2008)

Snooktoreds I should clarify Daddy daughter build = start with the heap below and refresh it, I haven't taken any pictures recently with the new stuff.









sand, sand some more and more then paint, then new everything, bimini, jackplate, trolling,battery, rod holders, etc Replaced everything on the trailer except the frame and with all stainless hardware. We then tore down the FREE (given to me by a good friend) 1972 25hp Evinrude rebuild from top to bottom and then painted it. I did this with my daughter to spend time with her and she loves to fish, good bonding time. We use the boat 2-3 times a week due to shes out of school but she starts the 6 grade this year so school first. 

Thank you for your advice, I'm starting to feel better about the flex


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## snooknreds2 (May 5, 2008)

> Snooktoreds I should clarify Daddy daughter build = start with the heap below and refresh it, I haven't taken any pictures recently with the new stuff.
> 
> 
> 
> ...


 [smiley=1-thumbsup1.gif] [smiley=1-thumbsup1.gif] [smiley=1-thumbsup1.gif]


THAT IS AWESOME!!! Not only did you get to spend time with your daughter but she is only in the 6th grade and know how to rig a boat and rebuild a motor. You are doing a fine job as a daddy!!!!

"any man can be a father but it takes someone special to be a daddy"


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## Ram5773 (Mar 20, 2008)

THANK YOU, i guess the fiberglass itchy scratchy brings you closer together ;D, she wasn't real happy about that. 

We are new at the fishing and boating but as long as we spend time together thats all that matters. I'll see if I can take a picture tonight of the finished project.


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## snooknreds2 (May 5, 2008)

A little to late now but to help in the future with the itchy glass sydrome:

1. wear a long sleeve shirt, no matter how hot it is it is better than sleeping with the glass on you.
2. Cover your arms and the shirt's sleeves with baby powder. I mean untill you are pure white, dont rub it in dont blow it off just cake it on thick
3. When done take a COLD shower for as long as you can stand it
4. Now take a hot shower (this one feels better than the first)
5. Go to bed NOT ITCHY!!!!


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## Ram5773 (Mar 20, 2008)

You sound very experienced in the fiberglass itch remedies.


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## Ram5773 (Mar 20, 2008)

Here are the current pictures
Jackplate fresh motor








dry storage, cooler on the right, rod holders








Freebee cleats from my buddies at Southco Marine








Oar holder idea








Final on th water








This took 5 months and was all done with help from daughter all the way


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## Brett (Jul 16, 2008)

That is one nice skiff. Very well done.
I can appreciate the time and effort.


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## backwaterbandits (Dec 15, 2006)

Nice work...Looks great!!


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## Un-shore (Sep 27, 2007)

Ah, I see now. The bottom of mine is the same but the floor is flat with a plywood sheet sandwiched in glass in the area I drew the black lines in. 










I know there is wood in there because water got in the stress cracks and soaked the wood. I've replaced it and hopefully will be floating soon. Nice skiff by the way! Looks nice and comfortable, I'm picturing you guys chillin' under that bimini top after a great morning of fishing.


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## Ram5773 (Mar 20, 2008)

Thank you everyone, we have only used it for a couple of months so far, no real exciting fish to speak off. Hopefully that will change soon, I just starting to explore my local area, here fishy, fishy


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## Ram5773 (Mar 20, 2008)

Houston we have a problem.   This happened to the boat today while out bouncing river  :'(










I'm thinking of adding stringers and a floor to help with the flex due to the problem above. What about removing the 2 dry storage areas( check out the prior pic's) and building long skinny dry storage box's that would run the sides of boat and open up the middle plus this might help reinforce the floor and stringers. Would that add any bracing for the boat???  I'm not a boat builder but some of you guy's on here do great work, Advice on performing this type of surgery??

Thanks


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## Un-shore (Sep 27, 2007)

Is the hull damaged? If not, maybe just repair the crack with glass and epoxy and go a little slower.


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## Ram5773 (Mar 20, 2008)

Ok I deserve that, hull doesn't appear damaged and doesn't leak. Will the epoxy and glass that you get from home depot work?? Just a question does fiberglass dry rot and become brittle?


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## B.Lee (Apr 29, 2008)

Looks like a weak contruction seam.  Are those boxes original?  


It looks to me like they were tabbed in with fiberglass mat, which isn't very strong structurally.  Even a small amount of flex could crack a joint tabbed with mat.  Without some cloth, it isn't that strong of a joint IMO.

It can easily be repaired, grind back to the glass, lay a strip or two of fiberglass cloth in there, and re-gelcoat it.  Good as new.


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## Ram5773 (Mar 20, 2008)

I found someone else with this boat same thing. I don't know about the boxes?? I'm toying with removing the dry storage and making strong new ones that will tie into the floor and run the sides of the boat but keep them shallow maybe 1ft wide or so to give more storage and strength. Would that add strength?


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## B.Lee (Apr 29, 2008)

If you stretch out the length of the boxes down the sides of the cockpit, it will greatly stiffen up the entire boat. Those smaller boxes probably don't do much for torsional rigidity, as you know.


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## Weedy (Dec 11, 2006)

Fiberglass WILL flex, Gelcoat will not! Most small stress cracks are from the glass flexing and the gel not! However, the crack you showed is more than that. Like said above, grind around and possibly thru the crack to make sure that it was prepped the correct way. Then just lay some new glass down and you will be good to go! Great job with the father/daughter build, my girl loves to go out, but heaven for bid she have to clean/work on it!


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## Ram5773 (Mar 20, 2008)

Thank you everyone for the advice, this is a fantastic forum, the best part about it is it is family orientated. I have seen pictures with parents that are in there 60'S fishing with there kids and people in there 30's fishing with there kids. I hope the Daddy daughter build goes well, she didn't the itchy part of the fiberglass, hope that doesn't discourage her from getting into the next build.

I'm going to temporarily fix it for now and use it until November and then gut it and do the whole boat over. I have a neighbor at Sea Ray that offered to help and get me the glass and resin at cost   I like the general layout of the Hewes Tail Fisher. If I can't afford a Tail Fisher I might as well build one. Poor mans Tail Fisher build here I come.

Richard


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## snooknreds2 (May 5, 2008)

> I like the general layout of the Hewes Tail Fisher. If I can't afford a Tail Fisher I might as well build one. Poor mans Tail Fisher build here I come.
> 
> Richard


Richard I can not wait to see this project. And I will have to ask for the plans as I will need to make one as well ;D


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## Ram5773 (Mar 20, 2008)

So far I have allot of good advice from allot of good people, I'm going to temporarily glass this area in the crack and use the boat until November and then tear her apart. I'll post the pictures as i go along on the build.


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