Rot Proofing Bunk Boards

[tboltmike]

I have read thru several threads on the bunk and roller debate and only saw a few mentions on bunk board rot. These discussions have gotten me to consider changing to bunks. Rot on the 3rd Coast is a major issue. So when I change, I want to take the best precautions to perserve the boards.

I am curious if you use any perservatives on your boards.

Around the house and fences, I have used Jasco copper napthinate. It is very thin and soaks into the wood. It is water based but won't wash off once set. I have used it on both plain and treated lumber. Anything that eats i is suppose to die.

Saw an article on using ethylene glycol, antifreeze to treat the wood. It is a biocide against rot, mildew and termites. The surface is saturated and allowed to soak in and will dry. As many coats as you wish can be applied. Once in and set, it is suppose to be good for a long time. I haven't tried this method but was recommended for treating transom wood and stringers before glassing in.

Thanks Mike

 

[fishrdan]

Re: Rot Proofing Bunk Boards

I used 2x6 redwood bunks on my last boat and they held up great for 10 years, no rot at all. Redwood isn't the strongest wood (actually pretty weak) but worked fine on my old 2500# boat.

Copper napathelate (sp) is supposed to be OK with metal, but I wouldn't use regular treated lumber as it will rust the metal hardware.

I tried to treat some plywood with a glycol/borax solution and wasn't happy with the results. After the wood was thoroughly dried (week in 100+ temps) the concoction would easily wash off the wood and I assume wash out of the wood with repeated dunkings.

 

[steelespike]

Re: Rot Proofing Bunk Boards

I have had very good luck using PT wood both ply and demension lumber.
In my opinion when you incapsulate wood all you do is create a way to
speed up rot when water does get in and it will.
The transom on my boat is about 27 years old unsealed or painted.
For 20 years boat was outside year round in the water about 8 months
a year.You just need to be sure the present type of PT wood is compatable with metal or sealed against contact.
If you let it dry you can seal and paint if you want.
My trailer with PT 2 X 4 bunkers about 20 years old has spent its life outside 10 years in the woods with carpet holding the moisture in.

 

[Bifflefan]

Re: Rot Proofing Bunk Boards

Why not used a non wood, product.
There are a lot of options out there that will last long after the rest of the trailer is rusted away. Put a strip of teflon on top of it and then make sure you strap her down tight and dont remove the safety chain till your already at the water.

 

[bruceb58]

Re: Rot Proofing Bunk Boards

Why not used a non wood, product.

Have you used a non-wood product? the ones I have seen are not strong enough to be used as trailer bunks.

 

[Bondo]

Re: Rot Proofing Bunk Boards

Ayuh,... P/T 2x's here....

 

[lckstckn2smknbrls]

Re: Rot Proofing Bunk Boards

I just replaced the bunks under my 14x36 Aluminum Jon boat with Cedar.

 

[Knightgang]

Re: Rot Proofing Bunk Boards

My bunks are demensional beams. something like 4"x8" beams about 8-10 ft long. Trailer is only 7 years old, but they still look brand new. They are covered with carpet, but left open on the bottom for water to drain out. They look great...

 

[tboltmike]

Re: Rot Proofing Bunk Boards

My bunks are demensional beams. something like 4"x8" beams about 8-10 ft long. Trailer is only 7 years old, but they still look brand new. They are covered with carpet, but left open on the bottom for water to drain out. They look great...

4"X8" beams. That sounds like drydocking the Queen Mary!!!

Are these treated?

 

[mrdancer]

Re: Rot Proofing Bunk Boards

Have you used a non-wood product? the ones I have seen are not strong enough to be used as trailer bunks.

You're right, they shouldn't be used as a direct replacement for wooden bunks, they do not have the span strength.

Replace the wooden bunks with angle-iron (or angle-aluminum), then bolt PVC lumber to the angle-iron. Then you have great strength, low-maintenance and low-profile. PVC is better than composite lumber as composite still contains wood and can stain and harbor mold.

 

[bruceb58]

Re: Rot Proofing Bunk Boards

Replace the wooden bunks with angle-iron (or angle-aluminum), then bolt PVC lumber to the angle-iron. Then you have great strength, low-maintenance and low-profile. PVC is better than composite lumber as composite still contains wood and can stain and harbor mold.

The problem with that is then the bunks won't conform to the shape of the hull.

 

[Knightgang]

Re: Rot Proofing Bunk Boards

4"X8" beams. That sounds like drydocking the Queen Mary!!!

Are these treated?

Don't know if they are treated, but my trailer looks like this. These types of trailers are very common in my area and FL, not sure about other places...

 

[109jb]

Re: Rot Proofing Bunk Boards

Pressure treated 2x's and stainless lag screws.

 

[wa_ssv197]

Re: Rot Proofing Bunk Boards

Check out what King Trailers use for bunks.
http://www.kingtrailers.com/standard_features.html