Outdoor furniture problem

juraj.kecso

Hi All,

Last year I bought an outdoor sofa set made of Acacia from Argos. I used No Nonsense outdoor furniture oil.

Over the year it developed this dirty looking patina and black watermarks. I wanted to start fresh, so I sanded the whole thing to bare wood and applied three coats of Liberton Boiled Linseed Oil (two coats diluted with white spirit and final coat full) as per instructions.

About two days after the final coat we had two or three days of occasional rain.

This morning I discovered pieces of the furniture have black marks and dirty looking watermarks, looking about the same as when I applied the No Nonsense oil.

Any advice on what this could be? I really wouldn't want to have to sand everything again and start from scratch.

EssexExile

It's outdoor furniture. It will be rained on, snowed on and hailed on. It will be frozen and baked by the sun, probably at the same time. It will get "weathered", accept it.

juraj.kecso

EssexExile said:

It's outdoor furniture. It will be rained on, snowed on and hailed on. It will be frozen and baked by the sun, probably at the same time. It will get "weathered", accept it.

Hi, I get that any timber will weather with time, which is why you treat it.

However, as you can see from the photos, this looks like someone spilled a bucket of dirty water on it. It's far from what you can consider a weathering process.

theonlywayisup

I have teak furniture which was an investment when it was purchased (many moons ago) but I clean it every year with a two part cleaner (Semco/Wessex) and then their sealer.  It is something that I researched for a long time for and have now used for 15 or so years.  It isn't cheap but it does stop the black (which is likely caused by your oil - I would never use oil on outdoor timber).  Oil can cause mildew and mould. 

This video is a good example of what it does https://www.youtube.com/watch?v=rQJI1NBmBLk&t=24s

travis-powers

Strip it back again and use osma stain oil, it’s expensive but goes a long way!
It’s what I use on timber cladding.

juraj.kecso

Could this be because we live in a seaside town? Maybe salt in the rainwater? Perhaps the oil wasn't fully cured?

There was nothing in the instructions about the oil having be protected from rain?

I am at the end of my tether here. 

-taff

It's mould or fungus from it being wet. Strip, dry, varnish with soething weatherproof.

theonlywayisup

You have no option but to strip it again and then leave it to dry fully. What you do then will determine what you do forever!

I live next to the see in Cornwall - I don't have this issue. 

juraj.kecso

theonlywayisup said:

You have no option but to strip it again and then leave it to dry fully. What you do then will determine what you do forever!

I live next to the see in Cornwall - I don't have this issue. 

Sure, and what exactly should I do? The wood was fully dry when I sanded it and oiled before.

Can you recommend any specific product?

theonlywayisup

juraj.kecso said:

theonlywayisup said:

You have no option but to strip it again and then leave it to dry fully. What you do then will determine what you do forever!

I live next to the see in Cornwall - I don't have this issue. 

Sure, and what exactly should I do? The wood was fully dry when I sanded it and oiled before.

Can you recommend any specific product?

I did in my post up there ^  Semco, but it is not cheap at £45 ish a litre.   However I live by the sea and my furniture isn't black and the litre of Semco lasts as you apply it sparingly. 

You will need to sand off or remove what you have applied and take it back to timber. [and I would then apply a cleaner] Then let it air dry.  Then seal with something other than teak/danish oil. 

GSDMum

I've had a good result in the past with Bar Keepers Friend - it contains Oxalic Acid, a wood bleacher - think Tesco stocks it. I mixed the powder to a paste and painted it on wood, leaving it overnight. In some bad areas I repeated it. The wood was hosed down and left to dry before sanding and treating.  

https://www.youtube.com/watch?v=Z4aKiJvQFXE

https://www.lakeland.co.uk/content/documents/BarKeepersFriend_Label_8868.pdf