6x6 fence post, treatment?

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Good afternoon.
I'm building a fence. 6x6 every eight feet for posts. Some will be in places that are
almost always wet (marsh).
The wood is .60 ACQ. I was gonna coat the end grain going into the ground with
some leftover Cabots oil stain to prevent wicking/rotting.
Any crazy tips to hold off rot?
 
Its already treated whatever you add will only get the surface.

The posts will rot right where they come out of the ground. Letting the treated wood dry for a month or two will allow it to soak in anything you add better.

My Dad brazed 3 or 4 round metal coolant containers together and would fill it with small fence posts (for his nursery) and then a creosote mix, then heat it with a gas blow torch for a few hours and then let it cool all the way.

OK, this was awhile ago, maybe late 1960s.
 
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These are KDAT. Kiln dried. Monday we are augering, so not much time to soak em
in oil or such (not that I could put 22 12' 6x6s one end in a pot of oil).
 
If you do not cut the post, it's already treated. If however, you cut the post, the interior of the wood will not be treated. What some recommend is that rather than using a 6 x 6 post, you use three 2 x 6's sandwiched together. This way, the treatment has gone all the way through the wood.

Barring that, you could always dip them in hot tar to seal the ends or spray them with automotive undercoating to seal the ends.
 
Roofing tar on the ends that contact the ground or water. They will eventually rot away but the tar will add several years to them. Why 6x6? You trying to keep King Kong in? LOL.
 
Originally Posted By: gman2304
Roofing tar on the ends that contact the ground or water. They will eventually rot away but the tar will add several years to them. Why 6x6? You trying to keep King Kong in? LOL.


I've thought of tar, may price a bucket of it...big posts because I'm in a very hurricane prone area
and even somewhat minor wind events push the sound water up a lot. During Irene the water rose eight feet.
Literally waves breaking in the yard.
 
The oldest and best method so far is to burn(scorch) the portion of the posts that's going to be underground.

Don't know if you guys use this method on the other side of the pound but we have miles of barbwire fences with posts burned like that and 70% of them are like the first day even after 40 years

This is what I'm talking about : http://www.eurofence.ro/ro/galerie/
 
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I did some 4x4s earlier this year for a fence.

The last one rotted at the demarcation point in classic fashion, and one heavy freezing rain storm broke it down.

First, the new posts were dried for as long as possible.
Next, linseed oil, two applications to the submerged part.
Once absorbed, a mix of linseed oil and mostly corn oil.
Then memorialized in concrete.

That corn oil polymerizes like a son of a gun, kind of like varnish that remains tacky. Water shouldn't be able to penetrate it now, or for a long time.
 
A friend of mine used to dunk the ends of her fence posts in burned motor oil before sinking them in the ground. I don't know whether it really worked but she and her husband said it helped keep the wood from rotting. They had a 20 acre horse farm/training facility up near Ocala and were always building a new fence in one area or another of the property.
 
Originally Posted By: gman2304
Roofing tar on the ends that contact the ground or water. They will eventually rot away but the tar will add several years to them. Why 6x6? You trying to keep King Kong in? LOL.


Yep, I was going to say try Henry's on the end of it.
 
Originally Posted By: Andy636
The oldest and best method so far is to burn(scorch) the portion of the posts that's going to be underground.

Don't know if you guys use this method on the other side of the pound but we have miles of barbwire fences with posts burned like that and 70% of them are like the first day even after 40 years

This is what I'm talking about : http://www.eurofence.ro/ro/galerie/


I don't know why I didn't think of this, but your post reminded me of it -

Back when my parents built their house, my mother wanted an old timey dinner bell in the yard, (she grew up in Georgia and it reminded her of working on the farm). My Dad went out in the woods and cut down a cypress tree. He then brought the tree home and built a fire, rolling that log around in the fire until the entire log was scorched. That pole with the bell on top sat in my parents yard for 30 years before it finally started giving out. Oddly enough, it rotted where the bolts passed through the wood at the top.

However, I would only try the scorched method on untreated wood as burning the treated wood releases all kinds of toxic chemicals.
 
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Originally Posted By: GreeCguy
Originally Posted By: Andy636
The oldest and best method so far is to burn(scorch) the portion of the posts that's going to be underground.

Don't know if you guys use this method on the other side of the pound but we have miles of barbwire fences with posts burned like that and 70% of them are like the first day even after 40 years

This is what I'm talking about : http://www.eurofence.ro/ro/galerie/


I don't know why I didn't think of this, but your post reminded me of it -

Back when my parents built their house, my mother wanted an old timey dinner bell in the yard, (she grew up in Georgia and it reminded her of working on the farm). My Dad went out in the woods and cut down a cypress tree. He then brought the tree home and built a fire, rolling that log around in the fire until the entire log was scorched. That pole with the bell on top sat in my parents yard for 30 years before it finally started giving out. Oddly enough, it rotted where the bolts passed through the wood at the top.

However, I would only try the scorched method on untreated wood as burning the treated wood releases all kinds of toxic chemicals.


Cypress would last forever untreated.
 
I've noticed over the years that after burning out a stump the charred areas are immune to insect and fungal damage. It is always the wood down below the charged area that would rot over time.
 
I'd search on "This old house", "Ask this old house" and Fine Homebuildings sites. FH has a discussion forum called "breaktime" you can also search.
 
Originally Posted By: Donald
Originally Posted By: GreeCguy
Originally Posted By: Andy636
The oldest and best method so far is to burn(scorch) the portion of the posts that's going to be underground.

Don't know if you guys use this method on the other side of the pound but we have miles of barbwire fences with posts burned like that and 70% of them are like the first day even after 40 years

This is what I'm talking about : http://www.eurofence.ro/ro/galerie/


I don't know why I didn't think of this, but your post reminded me of it -

Back when my parents built their house, my mother wanted an old timey dinner bell in the yard, (she grew up in Georgia and it reminded her of working on the farm). My Dad went out in the woods and cut down a cypress tree. He then brought the tree home and built a fire, rolling that log around in the fire until the entire log was scorched. That pole with the bell on top sat in my parents yard for 30 years before it finally started giving out. Oddly enough, it rotted where the bolts passed through the wood at the top.

However, I would only try the scorched method on untreated wood as burning the treated wood releases all kinds of toxic chemicals.


Cypress would last forever untreated.


Not true. While "old growth" cypress lasted a long time, the current stuff doesn't last as long. I've put in plenty of cypress fence post only to replace them within a five year time period.

My Dad also had some cypress boards stored in his barn for a number of years, (left over from when they built their house). I used these boards to make raised beds for my garden thinking they would last a long time, (they were rough cut boards - a full 2 inches by a full 10 inches). Termites ate them to pieces in about two years.

Even the post my Dad used for the dinner bell did not rot where it was scorched, it rotted where he bored holes through the wood to insert the bolts which held the bell.

However, here's an interesting side note regarding cypress. Where my parents live, there used to be a railroad bed that ran on the front of their property. The area was low and swampy and when the railroad vacated the right of way, my Dad bought the property. We leveled the roadbed and discovered the original builders had first laid a bed of cypress logs before building the roadbed, (a corduroy roadway). Those logs had laid there for over 100 years and yet, you could still see the axe marks from where they cut down the trees and the wood itself was hard as iron. We tried giving them away to several wood workers but no one wanted them. Sadly, we ended up burning them in a big bonfire.
 
Originally Posted By: hisilver
Good afternoon.
I'm building a fence. 6x6 every eight feet for posts. Some will be in places that are
almost always wet (marsh).
The wood is .60 ACQ. I was gonna coat the end grain going into the ground with
some leftover Cabots oil stain to prevent wicking/rotting.
Any crazy tips to hold off rot?


I'm a journeyman carpenter. The end grain of lumber is where 90% of the moisture comes from.
When lumber is cut the woods "veins"are cross-cut and that water evaporates fast. The water inside wicks out the ends because the cell walls protect the wood itself and its natures design to keep it in.
When dropping a post into the dirt a stain still allows water to wick up into the "veins" and since the bottom is buried in the ground the only way the water can escape is by exiting to top.
Wood fibres are like drinking straws,going from bottom to top. When its milled into dimensional lumber the edges and flats are cutting these straws or veins up the sides,so that part dries fast because the cell wall or straw has part of it sliced off.
To eliminate the wicking action from the bottom of the post you can wrap the entire buried end of the post in plastic or you need an actual sealant,not a stain.
Stain allows wood to breathe. It colours the cells of the wood. Paint on the other hand seals the lumber by encapsulating the stock.
Stain just colours the lumber.
Pm dermapaint. I'm sure he'll know exactly what to use in your application.
When I build decks I wrap the bottom of the post using vapour barrier made for 8' walls. The plastic comes up the post 4' and i drop it into a concrete pyle.
 
Cypress, redwood and juniper are all similar. But hedge apple AKA ironwood last nearly forever.
 
Well I ended up just using what's on hand. I slathered Cabot's Australian timber oil (contains linseed oil) until it would accept no more. Maybe five coats or so. That was yesterday, and today I gobbed on a lot of valspar duramax exterior paint which formed a nice 'rubbery' end seal. The end grain is so fully saturated with stuff water won't wick up it.
Next time I'll price some ipe pilings lol.
Thanks for the suggestions.
 
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