laminating transom

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Devojess

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I have a 1989 Four Winns 160 Freedom with a 90hp Johnson OB and I'm replacing the wood in the transom my question is when i go to double up the plywood should i put a layer of fiberglass and resin in between or just glue it then laminate it?
 
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BWT

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Re: laminating transom

You can do it either way; what kind of resin are you using? (polyester or epoxy)? If it's poly, I would seal each mounting face with a couple of coats and let it cure. Then sand it with 80 grit to scuff and level the surface then laminate the two halves together with a layer of 1.5oz mat between. If epoxy then I would still seal each face with a coat, let it tack up and laminate the two halves with epoxy and filler (Ex: If you're using West System, I would mix in some 403 filler for the lamination) and either clamp or screw the two halves together for curing..
 
Woodonglass

Woodonglass

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Re: laminating transom

Here's how I do a transom. Poly resin without CSM will dry brittle and IMHO is pretty much useless. The CSM is a must for strenth. Wrapping the edges is very important. I also drill 1/2" relief holes in various places in the wood so when I clamp the transom to the outerskin it allows the thickened resin to fill the holes and NOT have any air pockets form. Hope this helps.

(click to enlarge)
TransomBuild.jpg
 
Woodonglass

Woodonglass

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Re: laminating transom

OH and you're probably gunna want to know about the deck too...

(click to enlarge pics)

MakingDeck.jpg StringerandDeckLayup.jpg
 
D

Devojess

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Re: laminating transom

Thanks guys the info helps. I just wasn't sure to put CSM between. Wish me luck.
 
Yacht Dr.

Yacht Dr.

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Re: laminating transom

Welcome to Iboats Devojess :) ..

There is one thing that needs to be addressed before Anyone can answer your question.. What PLY are you using ???

Forget about the resins or glass right now.. We need the Ply structure. ( Marine,CDX,MDO etc )

There Is a different way to properly prep wood to wood..and wood to glass.. but ITS Dependent on the Wood for proper prep advice ;) ..

YD.
 
Woodonglass

Woodonglass

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Re: laminating transom

YD, is ABSOLUTELY Correct!!! Need to know Wood type first!! Good catch there Doc!!
 
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Devojess

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Re: laminating transom

I was going to use 3/4 inch bc plywood i heard that will work as long as its fully sealed and its a quality grade.
 
Cadwelder

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Re: laminating transom

Devojess said:
I was going to use 3/4 inch bc plywood i heard that will work as long as its fully sealed and its a quality grade.
Click to expand...

That's fine, just precoat the wood with resin, before the installation. That prevents dry spots from the wood soaking up the resin.
 
Woodonglass

Woodonglass

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Re: laminating transom

Yep my drawings and instructions were made assuming the use of standard Ext. Grade Plywood.
 
Yacht Dr.

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Re: laminating transom

Cadwelder said:
That's fine, just precoat the wood with resin, before the installation. That prevents dry spots from the wood soaking up the resin.
Click to expand...

And It Will drink alot of Resin :) . You will probably have to scuff the resin coated wood before you start your install.

But as CW said..you better make sure your wood does not soak up your resins whithin the clamping stages .. that Would create ( or has potential to create ) dry spots in the bonding.

YD.

PS. We LOVE pics on ongoing restos if you can :) .
 
Yacht Dr.

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Re: laminating transom

I just wanted to add..that I think this is another case of using BC ply VS. marine ( If it was available ).

Less time .. less hassle .. It works out the same $$ wise compared to "making your own MG" .. just more time and effort to get to the same calibre of MG.

MG is a totally different level of wood. Just the warping of other cut plys and the Thirsty nature of them..prep time etc.. in my book is not worth the potential problems that comes with skimping on costs with ply....

YD.
 
Cadwelder

Cadwelder

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Re: laminating transom

Yacht Dr. said:
I just wanted to add..that I think this is another case of using BC ply VS. marine ( If it was available ).

Less time .. less hassle .. It works out the same $$ wise compared to "making your own MG" .. just more time and effort to get to the same calibre of MG.

MG is a totally different level of wood. Just the warping of other cut plys and the Thirsty nature of them..prep time etc.. in my book is not worth the potential problems that comes with skimping on costs with ply....

YD.
Click to expand...

1000% correct, I just get tired of arguing the point.
 
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Devojess

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Re: laminating transom

Thanks everyone for the advise i will try to post pics to map the progress. I'm sure I will be looking for for more answers soon I'm a bit of a newbee at this.
 
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