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Is it safe to cut and plane H4 Sienna sleepers?

Finding My Feet

Is it safe to cut and plane H4 Sienna sleepers?

Hello Bunnings forum,

Im planning on building woodwork benches in my garage for woodworking.  To build the legs on for my main bench Id like to have 100x100 posts as this really makes the bench stable.  Ive built one before by gluing and bolting two 90x45 untreated pine pieces to make 90x90 legs but unfortunately you cannot buy 90x45 (or greater) untreated pine in Cairns due to the termite risk. 

So, I was considering buying 200x50 sleepers and cutting them down the middle and then putting them through my planer/thicknesser to finish the wood.  I wouldn't do this with ordinary H4 due to the CCA chemical but I've just read that the Sienna treatment is organic and works for vegetable gardens.

Is this safe to do? IS it safe to do with H2 treated pine?





Bunnings Team Member
Bunnings Team Member

Re: Is it safe to cut and plane H4 Sienna sleepers?

Welcome to the Bunnings Workshop community @Sacha2023. It's brilliant to have you join us, and many thanks for your question about cutting treated pine.


It is safe to cut, and thickness H2, H3 and H4 treated Pine. If you can get ahold of the sienna-treated sleepers, then there are no concerns at all. Even the arsenic-treated timbers are fine to cut and thickness as long as you wear gloves and a standard face mask. The issue with arsenic-based treated Pine is prolonged continuous exposure to it or using it for food preparation surfaces; that's why it can't be used on surfaces you often touch, like furniture, decks, seats or benchtops. 


If you didn't want to try thicknessing the sleepers, you could use the red H2-treated or H3-treated for your project. Red H2 timber and green H3 timber are not arsenic treated. If you were to use arsenic-based timber, I'd highly recommend you paint it to prevent contact.


Please let me know if you have any questions.




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Re: Is it safe to cut and plane H4 Sienna sleepers?

Thank you Mitchell,


Your answer has really helped me make my decision.  With the price of timber always going up Im always looking for the cheapest solution and this helps heaps.

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