I am working on a bracket under the decking for a bow mounted TM. As I was drafting plans, I remembered reading about a caution to not use a certain type of wood for projects with aluminum boats. Can anyone please clarify? What type of lumber am I safe to use?
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Treated wood on aluminum = bad?
- Thread starter Big Aug
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satx78247
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Big Aug,
TEAK, WHITE CEDAR, WHITE CYPRESS & REDWOOD in "plank lumber" and/or in plywood, MDO.
(Any of those will last a LONG, LONG time in fresh/salt water.)
"Pressure-treated" lumber is treated with POISON & a lot of it literally deteriorates aluminum & other metals.
yours, satx
TEAK, WHITE CEDAR, WHITE CYPRESS & REDWOOD in "plank lumber" and/or in plywood, MDO.
(Any of those will last a LONG, LONG time in fresh/salt water.)
"Pressure-treated" lumber is treated with POISON & a lot of it literally deteriorates aluminum & other metals.
yours, satx
joseph101088
Well-known member
treated wood has copper in it. since copper is higher on the galvanic scale than alluminum it causes the alluminum to corrode.
joseph101088
Well-known member
when i made my deck i used .5 oak plywood sealed it with a polyurathane. which just happened to be stain also. i then drove the screws in wet with polyurathane to seal the holes the screws created. i work around corrosion alot and the problem with preassure treated wood is the dissimilar metals not the wood.
Analog Kid
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any exterior grade ply wood that is not pressure treated will hold up well. Pt plywood and lumber is not somehow magically waterproof it's treated to keep insects out
satx78247
Well-known member
Analog Kid,
I use MDO plywood exclusively, as it lasts for DECADES in all weathers, when simply painted, as "big green signs" on the Interstate Highways. - Also it's CHEAP.
(T-111, made without the "grooves", is even cheaper than MDO & lasts a LONG time too.)
yours, satx
I use MDO plywood exclusively, as it lasts for DECADES in all weathers, when simply painted, as "big green signs" on the Interstate Highways. - Also it's CHEAP.
(T-111, made without the "grooves", is even cheaper than MDO & lasts a LONG time too.)
yours, satx
Analog Kid
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satx78247
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Analog Kid,
HD or LOWES (to my knowledge) doesn't sell MDO. - Call your local county highway shop (our county calls it "the county barn") and ask them where they buy their MDO.
(I buy my sheets at a low price from the same vendor as the county does AND for "small projects", I've been known to get MDO scraps FREE from the county barn scrap pile.)
best wishes on your project, satx
HD or LOWES (to my knowledge) doesn't sell MDO. - Call your local county highway shop (our county calls it "the county barn") and ask them where they buy their MDO.
(I buy my sheets at a low price from the same vendor as the county does AND for "small projects", I've been known to get MDO scraps FREE from the county barn scrap pile.)
best wishes on your project, satx
Island Man
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satx what kind of paint do you use on the MDO board?
lckstckn2smknbrls
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You want exterior grade plywood. Look for the X in the grading designation. ABX, BCX, CDX ect ect.
satx78247
Well-known member
Island Man,
I usually use plain old PORCH & DECK paint on MDO or T111. - IF you want the stuff to last for GENERATIONS seal it in epoxy & then paint it.
(The epoxy + paint is OVERKILL, imVho.)
yours, satx
I usually use plain old PORCH & DECK paint on MDO or T111. - IF you want the stuff to last for GENERATIONS seal it in epoxy & then paint it.
(The epoxy + paint is OVERKILL, imVho.)
yours, satx
rscottp
Well-known member
I'm also a big fan of MDO but is sure as hell isn't cheap in my neck of the woods. Only thing more expensive is cabinet grade plywood.
satx78247
Well-known member
rscottp,
Here in TX, MDO is cheap (at least as inexpensive as plain "good quality" exterior plywood), as compared to MARINE & lasts just as long. MDO however is downright PRICEY in "home improvement mega-stores", IF they have it at all.
Also, as it is made for sign-painters it takes paint well & finishes smoothly. - I know of several boats that have lasted for a long time with no more surface preparation that primer & paint. - One is a Phillip Bolger design called a CLAM SKIFF that has been used for over 2 decades as a commercial trotline boat 7/365 & based in Galveston County, TX.
Thus, "buried in a transom" or coated with epoxy as a sole (floor) of a tin hull, it should outlast everyone, who is old enough to read this post.
yours, satx
Here in TX, MDO is cheap (at least as inexpensive as plain "good quality" exterior plywood), as compared to MARINE & lasts just as long. MDO however is downright PRICEY in "home improvement mega-stores", IF they have it at all.
Also, as it is made for sign-painters it takes paint well & finishes smoothly. - I know of several boats that have lasted for a long time with no more surface preparation that primer & paint. - One is a Phillip Bolger design called a CLAM SKIFF that has been used for over 2 decades as a commercial trotline boat 7/365 & based in Galveston County, TX.
Thus, "buried in a transom" or coated with epoxy as a sole (floor) of a tin hull, it should outlast everyone, who is old enough to read this post.
yours, satx
rscottp
Well-known member
I live on the island of Martha's Vineyard and I am happy to say we don't have one of those mega home improvement stores here. My local lumber store carries MDO but doesn't have marine ply. I just looked at what I paid for MDO last year when I did my mod. $60 and $80 for 1/2 and 3/4 ply. A bit more than AC but less than Cabinet grade birch. It's great stuff, I have used it to build many things and have been very happy with it.
Good luck on your build!
Good luck on your build!
