How far does tanalising penetrate the end grain?

[Ferdinand]

Simple question - if I put up a post and rail fence, how far does pressure treated preservative go into the end grain?

 

eg If I want to saw the top of some posts to make them level, or at 30 degrees to help with rain runoff, how much typically can I take off without having substantially to re-treat the end grain? I use a post-rammer so it is easy to knock some in a bit more, though one can end up with a Paddington-Kitchen-Table effect (*). How much tolerance do I have?

 

I know there are those itty-bitty post caps or I can make little lead rain-bonnets, or make my own, but for a normal post-and-rail fence I do not really like the suburbiton look.

 

(And they cost more than the posts <:-) ! ).

 

F

 

* 
"Mr Curry's table seemed to have shrunk".

 

 

Edited June 26, 2017 by Ferdinand

[Cpd]

A lot will depend on the treatment process as to how well and how far the pressure treatment will go into the post.....  i use Tornado high quality posts with a long warrenty and an even longer life expectancy and when you cut a post in half you can see clearly how far the treatment has penetrated, cut a cheep post in half and its quite an amazing difference.

Tornado provide a additional treatment chemicals in a can for the times when you need to cut into a post and if this is generously applied to the end grain then thats the job done, no end caps or faffing around. 

[Gone West]

38 minutes ago, Ferdinand said:

Simple question - if I put up a post and rail fence, how far does pressure treated preservative go into the end grain?

 

It really does depend on the quality of the post. I've used posts with a 25 year guarantee and drilled through for fixing bolts and the treatment has gone all the way through. On the other hand some have had only 20mm of treatment.

[ToughButterCup]

Simple question: simple answer.

 

Concrete posts. If ya wanna get fancy, then paint them.

[Jeremy Harris]

I cut around 3 to 4 inches from the top of some driven-in posts that were around 100 to 120mm in diameter, to level them up for a fence, and there didn't seem to be any colour change.  I have a feeling that, under the sort of pressure used to force the preservative into the timber, that penetration into sections of up to around 150mm in diameter may well be close to 100% if it's done properly.  As above, I'd guess there is a fair bit of variation with price, as my understanding is that it takes longer to get the preservative to penetrate deeper, and so costs more in both time and the amount of treatment stuff used. 

 

 

[Ferdinand]

@Cpd Mine come from an agricultural supplier and I believe their supplier is Richard Burbidge.

 

Been using the supplier for decades. I can probably justify cutting down a 90mm tree stake to have a look in a couple of days.

 

@recoveringacademic this particular need is for a post and rail fence round a patio.

 

Ferdinand

Edited June 26, 2017 by Ferdinand

[ToughButterCup]

Wooden posts are fine for a couple of years; after that, you forget them and then, when you least suspect it, leaning on that particular wooden fence, drink in hand, romantic interlude warming up well, your eyes looking into the depths of your partners' , the thing breaks and you fall into a gorse bush.

 

Not fantasy in my case. Fact. Gimme concrete every time.

[Temp]

+1 to posts from agricultural suppliers. I've found proper P&R posts (which are 5*3 I think) and the large square posts (4*4) last a lot longer than the DIY store fence posts that are around 3*3.  Mine have been in 11 years with no sign of any issues. 

 

 

[Ferdinand]

48 minutes ago, recoveringacademic said:

Wooden posts are fine for a couple of years; after that, you forget them and then, when you least suspect it, leaning on that particular wooden fence, drink in hand, romantic interlude warming up well, your eyes looking into the depths of your partners' , the thing breaks and you fall into a gorse bush.

 

Not fantasy in my case. Fact. Gimme concrete every time.

 

Ouch. Gorse bushes are nearly as good as Pyracantha.

 

Not quite the same, but...

 

 

Edited June 26, 2017 by Ferdinand

[ToughButterCup]

I'd forgotten that sketch.

In my case it wasn't the breaking top rail, rather the second rail, the below-knee-height one that did for me. And if I remember correctly, she did look after me well. But, at this remove, maybe that's fantasy.

[Ferdinand]

I will slice up one of my posts into 50mm slices to see, and post results here.

 

In the meantime I may do a blog or thread about building a Ferdipatio. 

Edited June 26, 2017 by Ferdinand

[CC45]

Concrete for me as well.  As part of my work I visited a wood yard a few years ago and they had plenty of stories about modern treatments.  I went to their new outlet on Saturday and they were telling me that cheap posts are treated when wet and then dried - to save cost.  Stories of some lasting 2yrs before being replaced.  Also told me that CCA was being used again in NZ.  

[Ferdinand]

13 hours ago, Ferdinand said:

I will slice up one of my posts into 50mm slices to see, and post results here.

 

In the meantime I may do a blog or thread about building a Ferdipatio. 

 

Have now done these, cutting 300mm down into a relatively new (bought late last year) 90mm x 1.6m round pole in 75mm slices, and into one which has been in stock for a couple of years.

 

Interesting results ... blog article coming.

 

F