Transom Material

[Fishin_Rev]

I am thinking about replacing the wood that is just starting to split, looking for ideas or suggestions on the best replacement material

 

[JMichael]

Best is going to be to go back with an all aluminum transom so you never have to worry about replacing it again and it would be strong enough what ever your needs are. Next to that would be marine plywood. Because of the cross grain nature of plywood, it is stronger than single piece of wood of the same thickness. And being marine plywood, it has more layers than traditional plywood and uses and exterior rated glue. If both of those are out of the question, the next best IMO would be exterior plywood coated with 3-4 coats of spar varnish. Never use pressure treated wood of any sort in your aluminum boat, it will have ill effects on the structure of your boat leaving pits and possibly holes in your boat.

 

[Buddychrist]

Cedar turns out really nice

 

[Andy Taylor]

Cedar is a very soft wood though, and not very strong.

 

[Buddychrist]

Cedar is a very soft wood though, and not very strong.

I think you need to read this

https://www.ehow.com/how_6352177_choose-wood-boat-transom.html

https://bobcedar.hubpages.com/hub/cedar-furniture

I've got a cedar cabinet that's used every day and it's 90 years old. It's pretty tough stuff.

 

[jigngrub]

Aluminum is too heavy and too expensive.

Marine plywood is too expensive.

Dimensional lumber like 2x6 and 2x8 etc. is weaker than laminated plywood.

The best bang for the buck is ABX plywood with Aruco brand being widely used. Seal your laminated (2 pieces glued and screwed together) with epoxy resin or exterior grade Spar urethane, 4 coats. Seal all penetrations (bolts, screws, etc.) with 3M 5200 marine sealant and your new transom will last for decades.

 

[bigwave]

Aluminum is too heavy and too expensive.

Marine plywood is too expensive.

Dimensional lumber like 2x6 and 2x8 etc. is weaker than laminated plywood.

The best bang for the buck is ABX plywood with Aruco brand being widely used. Seal your laminated (2 pieces glued and screwed together) with epoxy resin or exterior grade Spar urethane, 4 coats. Seal all penetrations (bolts, screws, etc.) with 3M 5200 marine sealant and your new transom will last for decades.

+2 exterior plywood, use titebond 3 to glue the pieces together. Should be solid as a rock.

 

[sr71]

+3.... Lowes "Aruco".....glue with Titebond "3"......stain with a water bases stain if desired....and I used 6+ coats of "Spar Urethane".

 

[DaveInGA]

Aluminum is too heavy and too expensive.
I weighed out the aluminum for the design I planned to use. It was lighter than the coated plywood I'm going to use. The aluminum cost wasn't more expensive after considering the cost of the plywood, glue, SS bolts/screws, epoxy resin, paint and marine sealant.

The REAL problem with aluminum is the price/cost of hiring a welder. To do the transom correctly, the aluminum certified welder/fabricator is going to charge $50.00 an hour. In the case of my transom, that translated into $650.00 labor to do things right. So if you can weld aluminum yourself or can find someone who won't charge a fortune, it can be done. And it is permanent fix, you won't EVER have to replace it unless it's damaged. Fix and forget.

So someone considering aluminum transom that has found a reasonable welder or can do it themselves and can find the aluminum at a reasonable price (doable, I did it) should consider how long they are going to own the boat. If the boat is NOT the last boat you'll ever buy, aluminum is certainly NOT the answer. If the boat is a small, inexpensive boat, aluminum is probably NOT the answer. If the boat is a more expensive boat, one you've had for years and plan to keep until the end, aluminum is probably the best answer, assuming you can afford the welder, can weld it yourself or have someone who will weld it reasonably.

Marine plywood is too expensive.
But is the best quality of plywood available for a transom from any perspective but cost and availability.

Dimensional lumber like 2x6 and 2x8 etc. is weaker than laminated plywood.
Yes, it is, if you're talking pine. Hardwoods can be a very different story, especially maple and oak. Maple is an excellent material for a transom.

The best bang for the buck is ABX plywood with Aruco brand being widely used.
If it's available in your area. I wasn't able to find Aruco. I also wasn't able to find ABX that had the proper sizes to fit the dimensions of my transom area.

Seal your laminated (2 pieces glued and screwed together) with epoxy resin or exterior grade Spar urethane, 4 coats. Seal all penetrations (bolts, screws, etc.) with 3M 5200 marine sealant and your new transom will last for decades.
I would add the following:
Epoxy resin is the better sealant choice, but is more expensive than Spar Urethane and will need to be painted/coated because it is not UV resistant. Use stainless steel screws to screw the plywood lamination together and for the penetration bolts/screws/etc. An excellent alternative to 3M 5200 is Loctite Pl S30 polyurethane sealant. You'll find it in the roof and flashing section of Home Depot or Lowe's. It is engineered to create long lasting water and weather proof seals, it's flexible and expands/contracts with the plywood, which does contract/expand with humidity. I've used it recently in several areas around my boat and it's a great sealant.

just my .02,