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Pulpo
25th August 2005, 06:05 PM
I have cut down 4 Eucalyptus trees.

Varying in diameter from 250mm to 150mm.

I have used the trees as posts, each 3.5 metres high.

They are starting to split on the surface, nothing structural.

What should I paint on them.

Thinking along the lines a few coats of Linseed oil.

Any thoughts would be greatly appreciated

Cheers

Pulpo

Jamster
25th August 2005, 10:53 PM
Ya have to let em season (too late)
So paintem like picasso

Skew ChiDAMN!!
25th August 2005, 11:57 PM
I have cut down 4 Eucalyptus trees.
Varying in diameter from 250mm to 150mm.
I have used the trees as posts, each 3.5 metres high.
They are starting to split on the surface, nothing structural.
What should I paint on them.
Thinking along the lines a few coats of Linseed oil.

Jamster got it mostly right. They should've been cured or at least sealed first to reduce the drying rate. Too late to prevent it, but the rate can be slowed down, possibly stopped but I really wouldn't count on that.

Trick is to seal the wood, so water-based products are useless. Whatever product you use, you'll probably need to repaint on an annual basis, at least until the wood has cured. This'll take about 1year extra for every 1" of diameter... ;)

Linseed will work, Decking Oil or a good non-waterbased paint might be a more economical way to go, if colour doesn't matter. Off the top of my head, nothing else would really work much better and would probably be more expensive, as most also have a cosmetic component.

Ideally you'd need to concentrate on the end-grain and the internal surfaces of the cracks as these are where most of the water loss will be... If you can get to the end-grain take a close look and see whether it has radial or cupped shakes. If so, structural integrity will be compromised, the same way that two pieces of 4"x2" aren't quite the same as one 4"x4".

custos
26th August 2005, 01:54 PM
Reminds me of some fence posts I saw on a holiday in Vanuatu. They were obviously used right after being cut down because they had started to sprout! The soil is so fertile that cut logs stuck in the ground would take root. :)

Pulpo
26th August 2005, 04:58 PM
The posts are concreted into the ground.

So if I used linseed oil would that need to be done annually?

What if I just paint it?

I figured at the time it did not matter too much, now I'm not so sure.

Thanks for the advice.

Pulpo

elphingirl
26th August 2005, 07:08 PM
I think any treatments need to be renewed frequesntly. When looking up info regarding sealing the hardwood shiplap exterior cladding for our house, I found specific warnings against Linseed Oil, as it encourages mould and fungal growth. As an aside - if the posts were placed into the concrete footings when green, check whether they have contracted, and left a gap between the post and footing. Not only will they start to move around a bit, but water will get into this gap and damage the timber.
Cheers,
Justine

http://www.outdoorstructures.com.au/pdf/timcladding.pdf

Skew ChiDAMN!!
26th August 2005, 10:42 PM
The posts are concreted into the ground.

Ouch! elphingirl covered that.


So if I used linseed oil would that need to be done annually?

What if I just paint it?

Probably yes to both. It depends on their exposure to the elements. When the paint cracks or flakes it'll need a new coat. Linseed's harder to judge, but needs recoating more frequently and will probably need several heavy coats in the first place as it's absorbed fairly quickly.

If the posts are indoors, or in a protected spot (no direct sun or rain) then they'll need less maintenance.


BTW, out bush we used to use old sump oil on our shed poles and it worked well. I'm not to sure what the greenies would say to it now though... and you definitely didn't want to lean up against 'em! :D


I figured at the time it did not matter too much, now I'm not so sure.

If you put a new fence put up, it'll probably last for 10 years or so before it needs attention. If you seal it at the beginning and maintain it on a regular basis, it'll last a helluva lot longer.

Your posts are probably safe enough, but to keep 'em that way...

Pulpo
31st August 2005, 01:23 PM
The posts are in the elements some more so than others and all get alot of sun.

I have started spraying the linseed oil with mineral turps.

It certainly is soaking it up like a sponge.

Not sure if mould will be much of problem, time will tell.

The posts do not appear to have shrunk around the concrete base yet.

The goods news, every one who has seen them loves the look of them.

Thanks

Pulpo

Christopha
31st August 2005, 01:47 PM
I do hope you debarked them..... I have used creosote but it isn't nice stuff to apply

Pulpo
31st August 2005, 02:01 PM
For the part in the ground cresote was used although not enough.

Yes they were debarked.

Cheers

rod1949
31st August 2005, 05:20 PM
You can receive all the good intended advise in the world. In reality you won't stop them.