New slab of wood on a 12' pond hopper

[scipper77]

The transom wood on my 12' aluminum pond hopper is in need of replacement. It appears to be unfinished plywood held on by a number of mismatched fasteners.

My questions are simple. What kind of wood should I use for the new transom? What kind of fasteners? What should I use to seal/protect?

Without any guidance I would just use non treated plywood, paint it over with something to seal it a little, Attach with exterior grade hardware and use something along the lines of silicone on the back side of the wood to prevent water from leaking in.

I know that silicone is a poor choice for marine applications but this job should be easy enough that I won't mind repeating it every 3-5 years if need be. What I don't want is something that seals so well that the next time I need to remove the wood piece I will end up damaging the aluminum.

 

[Woodonglass]

Re: New slab of wood on a 12' pond hopper

Exterior Grade plywood is what most of the "Tinners" use. You can either use a couple of coats of Epoxy and then Paint it, or Just paint it with Several coats of Rustoleum Oil based Paint Or several coats of Marine varnish. Your choice. Stainless Steel hardware should be the way to attach it. With periodic maintenance and upkeep she'll last for decades.

 

[scipper77]

Re: New slab of wood on a 12' pond hopper

Do you mean the boat or the transomewill last for decades? It's allready a 1960 Cadillac. I'd say the boat will last for as long as I feel like using her and then some.

Any advice on what I can use to seal surface between the transom and the stern?

 

[Woodonglass]

Re: New slab of wood on a 12' pond hopper

I mean the transom wood. Typically you don't use anything between the aluminum and the Wood. Just seal all sides of the wood with your choice of sealer and then predrill your holes and seal them as well then attach with stainless hardware.

 

[lakelover]

Re: New slab of wood on a 12' pond hopper

I just did the same thing on a 42 year old 14' Ouachita tinny.

I would do as Woodonglass suggested, but I did not seal around the edges with caulking where it is against the transom as you mentioned. My thinking was that the seal wouldn't last, and it would do more to trap moisture behind the wood, rather than letting any water that gets behind it drain out and/or evaporate when the boat's out of water. I did use 3M 5200 on all the bolts going through the wood/transom.



Go with all stainless steel hardware and it will last for many years.

 

[scipper77]

Re: New slab of wood on a 12' pond hopper

I bought a slab of exterior grade plywood today. You can't get oil based paint in NY which sucks. I'm thinking I may just end up using some old water based deck stain that I have and I'll take my lumps when I end up repeating the process in a few years. What I am a little worried about is how to keep the fasteners from vibrating loose. I'll likely use stainless steel "Nylock" nuts.

 

[lakelover]

Re: New slab of wood on a 12' pond hopper

If you are wanting oil based paint, what is referred to here is something like Rustoleum Professional (not water based), it's available all over the place. I used SS bolts, flat washers and this type of nut on mine.

This is a picture of my seat board, but I used the same type on the transom board.

I ordered what I needed online, but you may find it easier to locate SS lock or star washers locally at HD, Lowe's, Tractor Supply etc. There shouldn't be any problem with them vibrating loose. Nylock would work fine, but they are more expensive.

 

[Woodonglass]

Re: New slab of wood on a 12' pond hopper

You can always put some locktite on em too!!!
Can you buy Boiled Linseed Oil in New York? Mineral Spirits? If so you can mix a 50/50 mix of BLO and MS and apply 3-4 coats of it to the Plywood. Let it dry for couple of days and then Paint it with house paint and it will last for a LOOOOOOOONNNNNNNNGGGGG time.

 

[scipper77]

Re: New slab of wood on a 12' pond hopper

I got some oil based exterior house paint from a coworker. I painted the transom wood and rather than three coats I continually reapplied while the paint was wet. I did it like this because I saw paint was being drawn into the end grain and I wanted to keep feeding it more paint while it was wicking.

 

[scipper77]

Re: New slab of wood on a 12' pond hopper

This morning I went to take the pond hopper out but the trailer lights were not working. By the time i had the wiring worked out it was a little late to start a fishing trip so I decided that today was the day to get the old rotting transome replaced.

The guy who gave me the oil based paint only had grey and that color is a pretty damn good color to use to blend in with the aluminum

I went to lowes and baught stainless hardware. I did not seal the screw holes yet but. Would automotive rtv be a good choi e to seal the hardware penetrations?

 

[Woodonglass]

Re: New slab of wood on a 12' pond hopper

IMHO Silicone has no place on a boat. 3M 4000 or 4200 would be my choice and you can get it at Ace, or Lowe's or H.D.

 

[scipper77]

Re: New slab of wood on a 12' pond hopper

So RTV is silicone based?? I thought it was basically a rubber base (Room Temp Vulcanized). My thinking is that if it is good enough for thermostats and water pumps that see the harsh enviroment of an engine bay, a stationary transom should be no problem.

O.K., I'll admit that even more of a motivation is that I already have some in my garage.

I think I'll put the boat in the water the way it is and see if the rubber washers that are on the inside of the transom are enough to seal up the leaks for now. If it does not leak I'll likely order some 5200 in the near future when I order some of that gluvit (sp??) to seal the seams. The rivits in the bow take on ever so small of an amount of water. The transom last season would take on a little water for the first 5 minutes and then swell up and seal.

So, seriously. Back to my first question, Is RTV silicone based??

 

[GWPSR]

Re: New slab of wood on a 12' pond hopper

So, seriously. Back to my first question, Is RTV silicone based??

Yup

 

[Woodonglass]

Re: New slab of wood on a 12' pond hopper

If you "Bing" it...

 

[scipper77]

Re: New slab of wood on a 12' pond hopper

Thank you guys. I should have just googled or binged it myself. I will find a more appropriate product than rtv.