What wood to use to replace transom?

[lswoody]

What kind of wood do I need to use to replace transom on my 14’ Jon boat? Also do I need to treat it with something to keep it from rotting? And is there a type of wood that will last that requires no treatment?

 

[lckstckn2smknbrls]

First never use pressure treated wood.
Every non treated wood will rot, use an exterior rated plywood like BCX.
I like the Old Timers Formula. Some use fiberglass resin with fiberglass or Epoxy resin,

 

[airshot]

Plywood will be the strongest, seal it up good and it will last longer than you will...no treated as the chemicals do not play well with the aluminum

 

[Tinhead1986]

Not to hijack this thread but i was going to ask the same questions. Being here in canada everything is $$$ and i can’t afford west system epoxy right now .If i used bondo fibreglass resin to seal the wood then paint it would it last or is spar urethane ,or oil based porch paint the best bet

 

[lckstckn2smknbrls]

Not to hijack this thread but i was going to ask the same questions. Being here in canada everything is $$$ and i can’t afford west system epoxy right now .If i used bondo fibreglass resin to seal the wood then paint it would it last or is spar urethane ,or oil based porch paint the best bet

Fiber glass resin without fiberglass cloth will not last long. It will peel off the wood.

 

[Sea Antsy]

? and what would be the down side of using some "PLASTIC" product..
STARBOARD..
AZK
TREX
a hunk of NSF cutting board..
no indication of how much ? repair or replacement is needed..
granted REPLACING a entire TRANSOM has some opportunities esp at the hull to transom connections..
I am interested in seeing where this goes..

 

[Tinhead1986]

Fiber glass resin without fiberglass cloth will not last long. It will peel off the wood.

how about using countertop epoxy resin to seal wood . i can get a 1 gallon kit for $99 plus tax vs $130 + for 1 quart of west systems

 

[airshot]

The two pieces of exterior plywood 1\2" thick on my jon boat are over 10 years old, treated with some home made stuff the painted over with rustoleum enamal....looks just like the day it was put on !!

 

[Tinhead1986]

Decided to go with .063 Aluminum checker $158 a sheet but i’ll never have to worry again

 

[Sea Antsy]

I am still confused with the definition of "REPLACE TRANSOM"...
? does that mean the whole transom from gunwale to gunwale and keel from top to bottom?...
I am just a hack but i cannot conceive of how to attach the transom to the rest of the boat ....
? am I missing something here..

 

[Tinhead1986]

I am still confused with the definition of "REPLACE TRANSOM"...
? does that mean the whole transom from gunwale to gunwale and keel from top to bottom?...
I am just a hack but i cannot conceive of how to attach the transom to the rest of the boat ....
? am I missing something here..

Replace the transom to me would mean the plywood transom at the back of the boat

 

[LDUBS]

I am still confused with the definition of "REPLACE TRANSOM"...
? does that mean the whole transom from gunwale to gunwale and keel from top to bottom?...
I am just a hack but i cannot conceive of how to attach the transom to the rest of the boat ....
? am I missing something here..

Replace the transom to me would mean the plywood transom at the back of the boat

Most aluminum boats use plywood to provide rigidity to the transom. The ply runs completely across the width of the transom. How far down from the top of the transom it extends depends on the boat design.

Like @Tinhead1986 says, most of the time when folks on this site refer to replacing the transom, it means that plywood. I"ve seen at least one thread that replaced the aluminum transom skin, but that is really an exception to the normal process discussed here.

Here is a link to another transom replacement thread - the first post includes a pic that shows the transom wood:

Lowe 16 transom replacement or renewal

 

[mbullen]

White Oak, Mahogany, or Marine Ply are the usual suspects.

 

[David Atkins]

I would look into COOSA BOARD as an alternative to plywood, does not absorb water and will not rot; glassing it in makes it even stronger!

 

[Sea Antsy]

Most aluminum boats use plywood to provide rigidity to the transom. The ply runs completely across the width of the transom. How far down from the top of the transom it extends depends on the boat design.

Like @Tinhead1986 says, most of the time when folks on this site refer to replacing the transom, it means that plywood. I"ve seen at least one thread that replaced the aluminum transom skin, but that is really an exception to the normal process discussed here.

Here is a link to another transom replacement thread - the first post includes a pic that shows the transom wood:

Lowe 16 transom replacement or renewal

Ahhhh... ok, thanks mucho for the clarification.. just a newbee here and I got lost in the "shorthand" of the vocab.
I have seen several tin boats with wooden stiffeners both up and down like my Duranautic DN-12 and completely across the back.
My Duranautic did have plywood there. and it was rotten.. I put AZK in and managed to tuck the top into the rolled cap on the top of the transom..
Some stainless screws, rubber washers and BOAT LIFE and good to go.

 

[Shootstraight]

Fiber glass resin without fiberglass cloth will not last long. It will peel off the wood.

I’d have to disagree on this one. It’s done all the time, I did it myself years ago. I mean, why would the cloth help the adhesion, it’s the resin that makes it stick. Maybe whoever you heard this from used wood that was not dried properly, moisture sure would could lack of adhesion.

 

[AlanT]

Why not use an exterior grade plywood or marine plywood and treat it with pentrating epoxy to make it waterproof? A quart of this stuff goes a long way.

https://www.totalboat.com/products/penetrating-epoxy-sealer?variant=43757090963680

 

[LaqueRatt]

I suspect the wood is for cushioning, to prevent the alum from cracking. Surely the alum is stronger than plywood. If or when I replace the transom wood, I'll likely go with exterior ply and a coat of either fiberglass resin or spar varnish. Spar varnish is basically made for this application isn't it?

 

[airshot]

Actually the wood is stronger, aluminum is thin and needs structure to make it strong. There are a number of wood sealers on the market, spar is not one. That is a finish coat on top. Some folks use a home made sealer with linseed oil and other like products that works well !! Seal each piece then laminate the various thicknesses together using water proof glue. Seal all edges with glue. After completely dry, coat with a good paint. Glass is not needed, but works well if you want the mess. This will last you the rest of your life, not sure how much longer you need it to last ?? Did a half assed job on my jon boat transom over 10 years back with cheap interior plywood as that was what I had. Today ...still looks like the day it was installed. The trick is to keep the wood from sitting in water, getting it wet is not an issue, but letting it set in water and soak is the real problem ! Look at how many folks tilt there boat back, let leaves and debris clog the drain and the wood sits in water....#1 reason for bad transom wood in small boats....

 

[LDUBS]

I’d have to disagree on this one. It’s done all the time, I did it myself years ago. I mean, why would the cloth help the adhesion, it’s the resin that makes it stick. Maybe whoever you heard this from used wood that was not dried properly, moisture sure would could lack of adhesion.

I think this may be a matter of terminology. When I hear "fiberglass resin" I think of polyester resin. Polyester resins are great for laying up layers of cloth but no so much alone as a sealer. For sealing transom wood, I would always use epoxy resin because it is significantly stronger and adheres much better. And of course, like all good things, it is also significantly more costly.