Thread: Working with Merbau (Kwila)

Wash it thoroughly with napisan or similar. Make sure to rinse well and let dry. Should do the trick. (or a brand name deck cleaner product).
tm

I used Organoil Wash-a-way when I built my merbau outdoor setting. Napisan as mentioned above also works. I kept away from other more toxic products as I also use wash-a-way to scrub my front veranda before recoating and there's lots of plants in the garden and blue tongue lizards.
Give it at least two days to dry throughly before coating.

I'll point out that the above two products (Napisan & Wash-away) don't 'seal & lock in' the tannins. Nothing will, short of encasing the timber in a thick impermeable coating.

What they do do, is remove the tannins from the surface and first mm or so, enough to enable the stain to take and set before the tannins slowly leech back to the surface from the heart of the wood.

This is the best you can realistically expect... but it should work for your situation.

Agree that wash-a-way etc. won't lock or seal in tannins but it did a great job on my tannin laden wood.
Almost 2 years since I washed my merbau timber with wash-a-way and assembled my outdoor table. Finished with Organoil furniture oil. Have re oiled it last month. No signs of any tannin bleed in that time. I did use high pressure cleaner when rinsing.
Also, lots of tannin on first clean of front veranda, last wash 2 months ago before recoating, very little on this wash and rinse with high pressure cleaner.
So whether the Organoil or the Ultradeck locks the tannins in, I don't know but I've had no problems with tannin bleed.

Thanks very much for your prompt help here. Much appreciated.

Yeh Like stated before "You can wash out surface tanin to work with oils..." Using any kind of synthetic Poly to try to seal outdoor timber can only result in "Yellowing" over time and the cracking and then near complete strip again, not worth it. Stick to a quality Oil and "Avoid Concrete" !!