Bunk boards for fiberglass hull?

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wmk0002

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I know to avoid treated boards for trailer bunks for aluminum boats. What about for fiberglass hulls? My dad has an older Procraft fish and ski that needs the bunks replaced so I was going to help fix his sometime soon.
 
I guess I'm old and set in my ways. I would just use non-treated 2x lumber and call it a day. It will last years before it needs to be replaced again. Those composite bunks are pretty nice, but $$$.
 
I guess I'm old and set in my ways. I would just use non-treated 2x lumber and call it a day. It will last years before it needs to be replaced again. Those composite bunks are pretty nice, but $$$.
That's my inclination too.
 
We use PT lumber, Cypress and even Cedar. But PT 90% of the time. White lumber will rot really fast unless you find a way to treat it.

For the cost and effort of pulling a boat and rebuilding the trailer, I would pick something that will last.

I have had PT bunks on all my aluminum boats for many years and have never had a problem with it ever. I think the carpet isolates the wood from the aluminum. No contact, so no electrolysis.

Now, if you are in salt water often, that may be a different story. I always put my boat in the lake after a trip to the salt.
 
I have had PT bunks on all my aluminum boats for many years and have never had a problem with it ever. I think the carpet isolates the wood from the aluminum. No contact, so no electrolysis.
Here too. The carpet can wear through eventually ant different points and by then the PT wood has dried out so much I've never seen a reaction. Gives time to replace the carpet. I use SS staples and always on the sides, no adhesive, and I leave the bottom open so as to not collect anything that'll promote rot.
 
I strongly disagree with using white lumber for bunks, especially on a fiberglass boat that won't have an issue regardless.

Once rot starts, it never stops, and I have done numerous repairs on boats where the bunk rotted around the bolts and came off, damaging the boat. Whether you wrap in carpet or use slick strips, get something that will last more than a couple of years.
 
I have akways used plain lumber due to aluminum boats, always get at least 6-8 years, sometimes more, life from my bunks. I carpet top and sides andbleave bottom open. I never use lag bolts to hold them, that will be an issue in short time. Carrage bolts thru only, either SS or galvanized. Keeping the bottom free of carpet allows the wood to breath and dry out. If your only getting a coyole years, then look some place else for your lumber....my deck is untreated lumber, no sealer, 22 years and still going strong !!
 
We use PT lumber, Cypress and even Cedar. But PT 90% of the time. White lumber will rot really fast unless you find a way to treat it.

For the cost and effort of pulling a boat and rebuilding the trailer, I would pick something that will last.

I have had PT bunks on all my aluminum boats for many years and have never had a problem with it ever. I think the carpet isolates the wood from the aluminum. No contact, so no electrolysis.

Now, if you are in salt water often, that may be a different story. I always put my boat in the lake after a trip to the salt.
I think the wet carpet will get impregnated with the copper as it leaches out of the PT bunks and be held against the aluminum hull.
 
Gatorbacks. Boat Bunk Cover Company | Claremont, MN & Vonore, TN | Gatorbak . I put these on my previous boat, a glass boat. Great product. Allows the bottom of the boat, in contact with the bunks, to dry out. Bottom of bunk boards is open, allowing the boards to dry out MUCH quicker. Made loading\unloading easier also.
I routed the top of the bunk boards, laid LED's in, to aid with loading at night.
No worries of using PT wood with this product, or other similar products, as it creates a solid barrier between boat and boards.
 
The previous owner of my bowrider, replaced the rollers with very supporting bunks. He did use treated wood and covered with carpet. After 20 years of ownership, no indiction of any problem. I cleaned and waxed the hull every year. I believe copper is used in anti-fowling bottom paint, so don't think can cause any problems with fiberglass.

If there is a chance that the trailer will be repurposed for an aluminum boat, use non-treated and seal them well before putting on the carpet.
 
I think the wet carpet will get impregnated with the copper as it leaches out of the PT bunks and be held against the aluminum hull.
This is theoretically possible, I have just never seen it in my years. I once had a customer bring his boat to me with this claim. But it turned out his battery had fallen over, and the acid ran along one of the ribs and ate a strip out of the bottom of the boat that happened to be over the bunk. The boat was totaled. Fortunately, he had insurance, and they covered it.

I currently have a 1994 boat that has PT floors, and with a piece of Tyvek between it and the boat stringers, with ZERO corrosion. In fact, that boat had the cleanest, driest subfloor I've ever seen! I think the PT fear is repeated often and exaggerated a bit. I'm using the Tyvek trick on my next build, but don't see a need to try using PT plywood. My current system works great, so I'm sticking with tried and true.

When I lived in Cape Canaveral, Florida, corrosion was a constant battle, so you had to rinse everything CONSTANTLY. The salt air even rusted cars terribly there.

Regardless of whether you use PT, white lumber or Cypress, Cedar or Redwood, this is a strong reason to use actual bunk carpet that dries quickly, not some house carpet that stays wet a long time. And if you fish in the salt, rinse, rinse. rinse. Your boat and bunk wood will thank you.
 
I guess I'm old and set in my ways. I would just use non-treated 2x lumber and call it a day. It will last years before it needs to be replaced again. Those composite bunks are pretty nice, but $$$.
I've also done this on all of my boat trailers that held....fiberglass and aluminum hulls. Never a single problem and they have lasted several years with freshwater launching. However, I am in the SoCal desert so they dry out pretty quickly. I carpet top and sides, leaving bottom uncovered.

I do like the Gatorbaks....I recently received a sample from them and it is a very stout product. Covers top and sides with thick ridges on top that allow water to run off.
 

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