Wood Hardener as End Grain Treatment

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Hi all,

Just wondered if anyone has any views on using a Wood Hardener (Tetrion, Ronseal etc) as a cut end grain treatment for decking boards? It seems like it would be more effective even than a water based end grain treatment but that might just be my feeling!

Thanks
 
It's not a bad idea. It should work, but I'm not sure if the presence of Tanlith would affect it and it certainly won't take decking oil/stain as well on the treated areas afterwards (as the hardened wood will be impervious to fluids), so it might look a bit light coloured in those areas unless you are careful how you apply it.
 
Fair point. It's actually Siberian Larch so it's not tanalised and was planning to let it weather. I have a little ronseal decking end grain sealer but even the clear one has a greenish tinge. I guess the hardener might still leave the timber porous?
 
I like to soak the cut ends in a spirit based wood preserver, poured into a large plastic paint tub. It only needs to be half an inch deep or so.

You can put them in after cutting and leave them while you get on with something else. Stand them in a corner to reduce the risk of falling over.

I like a green one as it's easy to recognise ends that have been treated.

Once dry you can use your usual oil or stain.
 
I guess the hardener might still leave the timber porous?
The other way round, surely? Wood hardener is basically a water-activated polyurethane, so it drops into the pores and converts any water to PU, so that would fill any pores.

If you want to stain timber afterwards, JohnDs approach is better
 
I use it to harden wood before using their epoxy resins. I have no idea how well it works at protecting the wood in isolation.
I've used Bonda Wood Hardener on several projects where we needed to repair rather than replace woodwork (mainly window fames, etc). Providing you remove the punky (rotten) fibres it is absorbed by the sound wood and sets, allowing you to saw, rout or chisel-away stuff the following day (and then re-treat) so that you can get repair pieces in nice and tight. It can foam slightly, and that foam can be removed with a sharp 2in chisel (i.e. a wide chisel) to get a flat surface once it has set. I imagine it will work well because it fills all the cells at the surface with PU resin, effectively turning the timber into a plastic/wood composite.

Tell you what, do a test piece, then go back in 20 years and see how well it's done - and post the results at the end of this thread. If I'm still on the perch by then I'll post a "thanks"...
 
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I've used Bonda Wood Hardener on several projects where we needed to repair rather than replace woodwork (mainly window fames, etc). Providing you remove the punky (rotten) fibres it is absorbed by the sound wood and sets, allowing you to saw, rout or chisel-away stuff the following day (and then re-treat) so that you can get repair pieces in nice and tight. It can foam slightly, and that foam can be removed with a sharp 2in chisel to get a flat surface once it has set. I imagine it will work well because it fills all the cells at the surface with PU resin, effectively turning the timber into plastic wood.

Tell you what, do a test piece then go back in 20 years and see how well it's done and post the results at the end of this thread. if I'm still on the perch I'll post a "thanks"...

Thanks

I will check out the Bonda stuff. So it is a bit like PU glue?

The Timbabuild stiff can be a bit temperamental. It is supposed to cure in an hour but I have known it to stay sticky for 3 days in April weather...

Edit- I will definitely try it

 
I will check out the Bonda stuff. So it is a bit like PU glue?
Not really, it's clearish and quite runny. Apply with a paintbrush (but wear disposable gloves, then kiss the brush goodbye because this stuff will cream cracker it). It does set a lot faster than overnight, probably an hour or so max in cool weather, but I've always been doing multiples, such as the sash window repair job we did on one building which ran to 88 sash windows in total. The reason I started using it was that it was a specified material on one C of E job I did. It works so I just stayed with it. As it sets it foams very slightly, which is partly why I clean it off with a chisel after it has set, but the residue sets in the brush's bristles and adding water to it just speeds up the process. Maybe next time I use it I should try using acetone to clean out the brush?
 
Not really, it's clearish and quite runny. Apply with a paintbrush (but wear disposable gloves, then kiss the brush goodbye because this stuff will cream cracker it). It does set a lot faster than overnight, probably an hour or so max in cool weather, but I've always been doing multiples, such as the sash window repair job we did on one building which ran to 88 sash windows in total. The reason I started using it was that it was a specified material on one C of E job I did. It works so I just stayed with it. As it sets it foams very slightly, which is partly why I clean it off with a chisel after it has set, but the residue sets in the brush's bristles and adding water to it just speeds up the process. Maybe next time I use it I should try using acetone to clean out the brush?

The PDF I linked to says use cellulose thinners to clean the brush.
 
Not something I normally have to hand, though. Acetone is something I do sometimes have as it is used to clean-out the foam guns we use with gun-grade foam, and it certainly does attack polyurethane-based compounds, hence my consideration. In reality the stuff starts foaming on the brush so fast that I tend to apply it really quickly and not worry too much about a pound shop brush. Wood hardener is not something to apply using your favourite Purdies, Woosters or Whistlers, I feel
 
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