TRANSOM WOOD! WHAT KIND TO USE AND WHERE TO FIND IT?

CATKRAZY

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Mar 28, 2007
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Hello again everyone. I was just wondering what type of wood is used when putting new Transom wood in a alum. boat? Also does anyone know where to buy this wood for boat transom and flooring? Thanks again to TASHASDADDY for the link left for me on the alum. boat transom replacement thread I started the other day. The pictures of that boat were almost identical to my boat. Nice to see exactly what im getting into with replaceing the wood in transom and flooring.
 

tashasdaddy

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Re: TRANSOM WOOD! WHAT KIND TO USE AND WHERE TO FIND IT?

you can use exterior solid core Grade Plywood, seal all the edges very well. marine plywood, would probably last about 2 years longer. the main thing is every time you penatrate the wood it has to be sealed. i use the same for my floor. if you have a 1 1/ inch thick transom, use 2 pieces of 3/4 ply. any lumber yard will have it.
 

andy6374

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Re: TRANSOM WOOD! WHAT KIND TO USE AND WHERE TO FIND IT?

Marine grade AB ply is the standard. Like Tashasdaddy said seal it on all edges but also you'll want to put a coat of resin on both sides before you apply any glass. The wood will be resin hungry (glass is resin hungry too), so if you dry to apply the glass over the dry wood you may end up with resin starved places.
 

erikgreen

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Re: TRANSOM WOOD! WHAT KIND TO USE AND WHERE TO FIND IT?

I'm planning on using 3/4" pressure treated ply for mine, because of the cost... $32 a sheet compared to $100 or so for marine.

From talking to everyone here and a few boating friends, the critical thing isn't so much the quality of the plywood involved, it's keeping the wood from getting wet, by sealing it completely in resin, sealing all penetrations well by pre-drilling and resin sealing, and making sure to promptly address any cracks in the resin coating.

Erik
 

Robj

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Re: TRANSOM WOOD! WHAT KIND TO USE AND WHERE TO FIND IT?

I would use pressure treated, douglas fir. Make sure it is very dry before you start. It is also recommended to use stainless steel fasteners. If you cannot find it, then I would use an exterior grade douglas fir plywood.
 

andy6374

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Re: TRANSOM WOOD! WHAT KIND TO USE AND WHERE TO FIND IT?

It IS about the quality of the wood. Plywood free of knots and voids.
 

croSSed

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Re: TRANSOM WOOD! WHAT KIND TO USE AND WHERE TO FIND IT?

I have to agree with andy5374. I wouldn't use anything but 3/4" marine grade for the transom.

TG
 

burroak

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Re: TRANSOM WOOD! WHAT KIND TO USE AND WHERE TO FIND IT?

Laminated beams from a builder supply will give you a 1 1/2" thick structural ply. The widths vary, but these can be found in the bargain bin area of most Menards, Lowes, HD. Save as much of the old transom as you can-makes for a great template. As mentioned in other posts, glassing the edges is well worth the time and materials. If the inside of the transom is to be mated up to an aluminum motorwell, clad that surface with appropriately colored coil stock from a siding supply business (contact cement will do). Seam seal the joint. It makes for a satisfying project.
 

Bob_VT

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Re: TRANSOM WOOD! WHAT KIND TO USE AND WHERE TO FIND IT?

If you want a good glue between the sheets of plywood..... use gorilla glue and shoot some stainless steel screws into the sheets being attached together. Drive them right home and they will just end up being sealed inside. Just plan ahead where holes will be drilled.
 

Robj

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Re: TRANSOM WOOD! WHAT KIND TO USE AND WHERE TO FIND IT?

I would use 5200 or Sikaflex to glue the ply together before I would use gorilla glue.
 

mikesea

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Re: TRANSOM WOOD! WHAT KIND TO USE AND WHERE TO FIND IT?

hey,Im in the "same boat"as you.Do a search on coosa fiberglass products.Its a bit more costly,but I bet it does a heck of a job,and once.
 

andy6374

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Re: TRANSOM WOOD! WHAT KIND TO USE AND WHERE TO FIND IT?

To laminate the two pieces of wood together. Mix up a batch of resin, cabosil and milled fibers. With a 1/4 notch trowel spread the mixture onto one of the sheets of plywood. Now take some 1.5 oz mat and wet it out on the other sheet of plywood. Then sandwich the two together and hold with screws or lots of clamps.

You'll want help with this one because you don't want the glass or the thickened resin t to begin curing before you squeeze em' together. Also, drill some relief holes in the plywood so excess resin can escape. Just fill those holes later with a simliar mixture of the thickened resin you made before.
 

CATKRAZY

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Re: TRANSOM WOOD! WHAT KIND TO USE AND WHERE TO FIND IT?

thanks guys for all the info im sure to have other questions as this is my very first time ever doing any work on a boat so far its going pretty smooth i got all the old floor and transom wood out and able to use most of them for templates to make new pieces so i guess so far so good i have a pic or 2 of the boat before starting the project but unfortunatly i didnt think to take pics as i was tearing it down. as soon as i can figure out how to put my pics on here i will show everyone what the boat looked like before starting the rebuild and some that i take as im putting it back together again
 

erikgreen

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Re: TRANSOM WOOD! WHAT KIND TO USE AND WHERE TO FIND IT?

Well, my using two sheets of 3/4 inch pressure treated will exceed the original builder's specifications for the boat... from the looks of the wood I've been pulling out, it was built with exterior grade ply with most of the knots cut out, and it wasn't fully encapsulated.

I admire those of you that use nothing but the best materials for your boats, but I really do believe that craftsmanship and maintenance weigh far more heavily than "perfect" materials.

For those of you stating you'd only use marine ply, why would you not use Nidacore or a similar foam board? It's even stronger, right?

For me, PT is better than what the boat originally had. I have to assume the designer took into account the strength of the original junk ply when he made safety calculations, so as long as the ply I use is better, I should be on the strong side of the safety fence. Especially if I pre-test for voids (tap test) and encapsulate with epoxy this time.

Erik
 

croSSed

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Re: TRANSOM WOOD! WHAT KIND TO USE AND WHERE TO FIND IT?

As far as foam as core material - The manufacturer of the foam I was considering recommended against using the foam as a 1 to 1 swap for wood. There was some question as to the use of foam core, and it was more than twice as expensive as marine grade ply. The marine grade ply was a known commodity. I have been advised more than once that if you properly encapsulate wood there is no reason why you should ever have to deal with rot. The wood in a boat, if PROPERLY sealed, should outlast you. Those are all the reasons, after considering closed cel foam as core material, why I went with wood.

TG
 

andy6374

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Re: TRANSOM WOOD! WHAT KIND TO USE AND WHERE TO FIND IT?

Its hard to beat marine ply for transoms. As to the Nida core, while it would work great for a deck, it wouldn't fair that well for transom core. The compressive strength is so so since it is mostly air inside those honey combs.

Marine ply isn't the best material, but rather the standard. Marine ply and poly resin. Those two materials and quality craftsmanship (as you mentioned) are the keys to good repair.

You can do better and spend more if you want...merchanti, okumme (or however you spell them). You could even go composite, Coosa blueboard is an alternative. Go from poly, to vinylester or even epoxy. The sky is the limit.
 

ifishforfood

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Re: TRANSOM WOOD! WHAT KIND TO USE AND WHERE TO FIND IT?

I used Microlam in my transom and sealed it completly with epoxy resin.Very strong and durable with no problems(boat is a 1973 14' aluminum MirroCraft Commander.Powered with 15hp Johnson[1981]).Boat came with long-shaft outboard and was made for short-shaft so I made the boat fit the outboard.
 

Bob_VT

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Re: TRANSOM WOOD! WHAT KIND TO USE AND WHERE TO FIND IT?

I used Microlam in my transom and sealed it completly with epoxy resin.Very strong and durable with no problems(boat is a 1973 14' aluminum MirroCraft Commander.Powered with 15hp Johnson[1981]).Boat came with long-shaft outboard and was made for short-shaft so I made the boat fit the outboard.

Welcome to iboats.

This is a post from 3 years ago and the original poster has not been back in 3 years.

We really do appreciate input and advice of "how I did it" etc..... ;) but we like to stay with the current problems.

You will find that the restoration section is really active and we can always use another point of view.

Once again...... Welcome.
 
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