What sealant works best for keeping water out of wood?

[Paschale]

Hi guys,

I need to know the water sealer you guys have had the best luck with.  I'm replacing the base of my porch pillar.  I didn't want to use pressure treated wood, since I needed to use my jointer, planer and router.  I decided to use white oak, and I need to treat the bottom of the pillar, which will be resting on an elevated chunk of concrete.  The original survived like that for 70 years, so I'm hoping to get some good life with this replacement.  But...what's the best to seal the bottom with?  I mentioned Thompson's water seal to my dad, and he said that it wasn't that good after all.  What do you guys recommend for the application I'm doing?

Thanks!

Dan

PS  As I'm thinking about this some more...the thought comes to mind of putting on the bottom of this wood some sort or resin, similar to what's put on boats.  That might work...

[Paschale]

Well...I did a little searching on the FF...and came up with this post from Cktate:

I've made quite a bit of waterproofing for my house using paraffin, mineral spirits, and linseed oil. The recipe is pretty easy to find it's an old timy waterproofing do it yourself mixture.  You have to cook it up just a bit. I'm of the opinion that it beats something like T. Waterseal all to pieces. Haven't done the whole house yet, wanted to make sure the boards were fully dry.  So a little later on I'm going to spray the whole outside of the house with this mixture.  With one exception.  I'm going to experiment and add a bit of zinc oxide or zinc sulfate to the stuff so it will also  have UV protection.

Disclaimer:  AM NOT recommending anyone else try this without doing a bit of research, and have no idea if it'd help the end of a log. 

I need to use the search feature more often!

[Don P]

That sounds like part of the old Forest Products Labs recipe. It used to have some fungicide in it if I remember right.

If I have to set end grain on the floor, I rout a cross in the post bottom about 1/4x1/4 to fool myself into thinking it gets some ventilation. A base block that gets it off the floor is good. Tarpaper helps. I've drilled and inserted Impel rods, the borate sticks, into post bases too. I've also got some Abatron epoxy wood consolidant that makes a pretty good coating. It can be thinned and soaked into wood, white oak doesn't soak or treat much though. I do wonder when I soak something totally impervious into wood if I'm not trapping moisture behind a non breathing finish and actually acceleratating rot. The theory behind the FPL recipe, if I remember right, was to repel liquid water yet allow water vapor to pass through so the wood could quickly dry back out if water got through the finish.

I just looked it up over there, here is the newer form of the FPL recipe.
http://www.fpl.fs.fed.us/documnts/finlines/willi02a.pdf

[Paschale]

Thanks for the reply Don.

Would it be wise to screw a galvanized steel disc to the bottom, and slather something on the wood before doing that?   ???

[CHARLIE]

Paschale, here's a product line that might serve you well. 
http://www.wolman.com/product_category.asp?CatID=82
http://www.wolman.com/product_detail.asp?ProductID=15

[Paschale]

Well, so I followed Charlie's recommendation, and saw that Menard's carried this product.  While I was there snooping around, I found something that should take it one step further.  It's called Cuprinol No. 10 Green Preservative.  It's specifically designed for applications where wood is in direct contact either with water or soil.  According to their promotional material, it's pretty well known in the boat building community.  I found information about it at a boatbuilding website in fact.

http://www.jamestowndistributors.com/decoder_cuprinolgreen.jsp

I think I'll throw a couple of coats of the stuff on the white oak and hope for the best. 

[Timburr]

An olde British recipe, was cook up equal parts of Stockholm tar, terpentine and linseed oil....a similar method used by Cktate.
Stockholm tar was used here for centuries for water-proofing the caulking on ships. It seals and keeps the nasties at bay.
Linseed oil repels the water and terps or mineral spirits helps it all get into the wood.

I may be wrong here, but isn't Cuprinol a copper-chrome-arsenic based compound?

[Minnesota_boy]

The Material safety data sheet for Cuprinol can be found at

http://ptcl.chem.ox.ac.uk/MSDS/CO/copper_naphthenate.html[url]

The Chromium Copper Arsenate is CCA, also known as Osmose and at least a dozen other trade names.

[CHARLIE]

Timburr, a replica of one of Columbus' ship, The Nina,  came up the Mississippi River and then into the St. Croix River to dock at Hudson, Wisconsin.  Donna and I went to visit it and I noticed it was solid black. I asked one of the crew members why the wood was black and he told me the formula you mentioned was how they used to preserve the wood on the sailing ships. It turned them black, but I guess it was effecient.