bairdy380
12th July 2018, 09:04 PM
Gday team, been a while. Building an outdoor "room" that has a solid merbau bench/servery that is 4m x 450 x 25. Wondering what recommendations to seal as it will be sat on and does have direct exposure to elements.
Advice appreciated
Cheers
cava
12th July 2018, 09:14 PM
Looking forward to seeing the responses for this, as I am just finishing an outside merbau shoe box/rack that will be partially exposed to the elements.
Personally, I was considering tung oil for ease of application and reapplication as required.
bairdy380
15th July 2018, 03:00 PM
Going to hone my query slightly as search isn't quite delivering. The servery is also a bench seat, so there will be direct contact with the surface. I was thinking a tung oil base and a 3 coat urethane finish. It is 100% out in the weather.
Cheers
themage21
16th July 2018, 11:28 AM
If it's right out there in the sun, the urethane will die within a year or two - I'm sure it'll get mentioned, but a member made an absolutely spanking set of wooden boxes for his ute that died within a year or so due to issues with the urethane finish (among other minor dramas). Unfortunately the pictures were lost a few years ago. The lesson was that you're fighting a losing battle by putting a protective system on it that needs to be stripped off in order to be maintained.
Also, tung oil doesn't have the greatest UV resistance and will yellow quite quickly under full sun conditions before degrading (although maintenance is easy enough, oxalic acid clean, rinse, dry and re-apply) - although the yellowing shouldn't be a major drama for merbau.
Given that you're using merbau, you'll have the option of going with any number of reputable decking oils that are already pre-tinted the right colour, which will also provide the necessary UV protection as well. That's a pretty good option, particularly if you go with one of the more reputable brands (e.g. Cetol). Maintenance is easy, as they're designed to be looked after regularly.
If you want (nearly) clear, I have a product that I use for outdoor work that is a satin or gloss called Deks Olje. I've got it on a bench that is in partial exposure all year around and the gloss finish is about to hit 2 years without any noticeable degradation. For full sun applications, I'm waiting on the result of the cubby house, particularly once this next summer draws to a close. That said, it's easy to use, apply and maintain. Once it goes off, it's also safe for sitting on for all colours of clothing. It does change the colour of the timber - for something like merbau, that is likely to be a darkening of the red/purple tones to their wet colour. Lighter timbers get a distinct yellow cast to them.
Before you pick a product - consider how much direct sun it will get. Full sun in summer will mean an outdoor rated product is absolutely necessary. If it's in shade most of the time, you can probably tone down the need for something nuclear rated.