Cabin rebuilt Project - cabin to deck joint

[dzausta]

Hi All
Ok so I decided to do some mods on my boat and decided to change the shape of the cabin as the one fitted on the boat didnt quiet suit my needs and was leaving much of unused valuable space. Before starting this project i had no fiberglass experience so i knew I was in for a lot of research and hard work. After a lot of reading and research i decided to cut out the current cabin and replace it with a new moulded one that i have made up. Thought I would document the project as I couldn't find any other similar projects, maybe there's a reason for that? Well seeing what another member OOPS! got himself into in his project gave me courage to open up my own can of worms.

Here goes

Bellow you can see the photo of my sexc boat its a 19 " Fiberglass hull, unsure of the make. So on the photo you can see that the current cabin set up had a lot of wasted space on the bow side.


Cabin shape that i was aiming for.


And here follows the mess I got myself into. Cutting out the cabin left me with a giant tinnie.


After drawing up the shape I made up a jig and laminated some marine plywood to form cabin sides.


joined up two halves together using scarph joints and prefitted. Wooden sides will be fiberglassed to the deck. (here lies my question)

 

[island mike]

Re: Cabin rebuilt Project - cabin to deck joint

I used pb and fiberglass,Strong as can be,

 

[island mike]

Re: Cabin rebuilt Project - cabin to deck joint

View attachment 123910I used pb and fiberglass,Strong as can be,

the pb to stick the cabin to the boat and the fiberglass on both sides of the cabin,and on boat(5 inches high or so)to reinforce the joint,(make sure to grind away any gelcoat were the cabin will be joined to the boat or else it will not stick.)
Regards I mike

 

[dzausta]

Re: Cabin rebuilt Project - cabin to deck joint

Had to make this post in two gos as it was too long.

How do I glass in the plywood laminate to the deck? What sort of joint should I use? I am using west system epoxy for this project.

Look from the inside.
View attachment 123909

Couple of joints considered.
View attachment 123911

I have looked into few joint types but not sure what would be most suited for this application. the original cabin side was just glass molded upwards. Ill attach some illustrations. Are these joints suitable for this part of the boat should i make it stiff or allow some flex?

 

[island mike]

Re: Cabin rebuilt Project - cabin to deck joint

Had to make this post in two gos as it was too long.

How do I glass in the plywood laminate to the deck? What sort of joint should I use? I am using west system epoxy for this project.

Look from the inside.
View attachment 123909

Couple of joints considered.
View attachment 123911

I have looked into few joint types but not sure what would be most suited for this application. the original cabin side was just glass molded upwards. Ill attach some illustrations. Are these joints suitable for this part of the boat should i make it stiff or allow some flex?

Sorry pics not coming through,Try the advanced button when posting.
West system is good. The way I explained is a very strong joint.No flex,Make it stiff.
Regards i mike

 

[island mike]

Re: Cabin rebuilt Project - cabin to deck joint

You might be making it more difficult that you should,Just stick the cabin ontop of your hull with west system addhesive filler,Then laminate on the inside and outside of cabin,You might want to use some ply peel to get a nice smooth result.Why the need for all kinds of joints?trust me fiberglass is very strong. This is how I attached my pilothouse to my hull and it aint coming off even if I wanted to!
I mike.

 

[island mike]

Re: Cabin rebuilt Project - cabin to deck joint

Wheres the beef???

 

[chriscraft254]

Re: Cabin rebuilt Project - cabin to deck joint

Subscibed! I love transformation projects. I agree with whats already been said. You should be able to just join it outside and inside and be good to go. Just make sure you grind back far enough on the forward deck to get a good wide bond and room to fair it out. Also make sure the deck your setting the upper structure on is strong enough to carry the above weight with support of some kind.

 

[island mike]

Re: Cabin rebuilt Project - cabin to deck joint

Subscibed! I love transformation projects. I agree with whats already been said. You should be able to just join it outside and inside and be good to go. Just make sure you grind back far enough on the forward deck to get a good wide bond and room to fair it out. Also make sure the deck your setting the upper structure on is strong enough to carry the above weight with support of some kind.

Think hes gone....(?)

 

[dzausta]

Re: Cabin rebuilt Project - cabin to deck joint

Hey
Thanks guys. Mike im not gone I keep on re-checking the post for any new piece of the advice and have been waiting to get back to the office so i can re post the photos that are missing.

A quick illustration of how I was thinking of joining the two.


could not decide if I should also have a fillet from the inside as well or if one was enough.

 

[island mike]

Re: Cabin rebuilt Project - cabin to deck joint reply from mike

Re: Cabin rebuilt Project - cabin to deck joint reply from mike

Hey
Thanks guys. Mike im not gone I keep on re-checking the post for any new piece of the advice and have been waiting to get back to the office so i can re post the photos that are missing.

A quick illustration of how I was thinking of joining the two.
View attachment 124494 Yepper,THATS the way to go..Its really up to you one fillet or two on both sides,As long as you glass on both sides,You should be fine,One thing to remember..Fiberglass does not like sharp corners or edges,It will not adhere well and cause lots of airpockets.
Whatever you decide,though I would fillet and fiber right after that.Not waiting for the fillet to dry and fibering over it will eliminate the need for sanding etc. It also makes for a super tight bond between the two.Good luck I mike


could not decide if I should also have a fillet from the inside as well or if one was enough.

 

[island mike]

Re: Cabin rebuilt Project - cabin to deck joint reply from mike

Re: Cabin rebuilt Project - cabin to deck joint reply from mike

Dont know what happened but my reply is submitted in your post above here...

 

[dzausta]

Re: Cabin rebuilt Project - cabin to deck joint reply from mike

Re: Cabin rebuilt Project - cabin to deck joint reply from mike

Just have to wait for the weekend to align and glass it all in.
I got 12 oz biax ++45 tape thinking of 3 layers. will make each wider... just want to know it that is sufficient. what did you use? I know its just a guess.

 

[island mike]

Re: Cabin rebuilt Project - cabin to deck joint reply from mike

Re: Cabin rebuilt Project - cabin to deck joint reply from mike

Just have to wait for the weekend to align and glass it all in.
I got 12 oz biax ++45 tape thinking of 3 layers. will make each wider... just want to know it that is sufficient. what did you use? I know its just a guess.

3 layers of biaxel sounds a little like overkill to me but hey go for it .Thought about using ply peel yet? It makes a hell of a difference,And almost no sanding...

 

[island mike]

Re: Cabin rebuilt Project - cabin to deck joint reply from mike

Re: Cabin rebuilt Project - cabin to deck joint reply from mike

So where did you go?
Any pics of the progress yet?
Island mike

 

[island mike]

Re: Cabin rebuilt Project - cabin to deck joint reply from mike

Re: Cabin rebuilt Project - cabin to deck joint reply from mike

Well thanks a lot then.

 

[dzausta]

Re: Cabin rebuilt Project - cabin to deck joint reply from mike

Re: Cabin rebuilt Project - cabin to deck joint reply from mike

Hey I'm back from the dead, thanks for your help Mike. Its been a long time but a lot has happened in my life. Crashing a motorbike and cold weather has set me back a while but I'm back into it now. I'm sorting out all my photos atm and will make few posts in next few days.

 

[dzausta]

Re: Cabin rebuilt Project - cabin to deck joint

Subscibed! I love transformation projects. I agree with whats already been said. You should be able to just join it outside and inside and be good to go. Just make sure you grind back far enough on the forward deck to get a good wide bond and room to fair it out. Also make sure the deck your setting the upper structure on is strong enough to carry the above weight with support of some kind.

Thanks for joining in.

 

[dzausta]

Re: Cabin rebuilt Project - cabin to deck joint

OK since my last update I decided not to glass the plywood frame to the deck just yet. What I did was build a frame to hold my laminate in place using a 3 x 4 planks and cut out plywood that I used to construct the laminating jig. That way I was able to work around the frame without it loosing shape as it was very flimsy.

 

[dzausta]

Re: Cabin rebuilt Project - cabin to deck joint

From there I decided to go with rigid expandable foam and build a rough shape of the cabin. I did this using plain old cardboard to build walls and pour the foam in. When pouring foam use any sort of pva sheets or tape to cover areas you don?t want the foam sticking to, this stuff will stick to almost anything and the only way to get it off is to sand it off. Once the foam was poured and dried I went around the edges with a hand saw and roughly cut the shape I was after.