Water stain

[Shedhand]

Some years ago a made a hall table from Tasmanian Oak inlaid with strips of Myrtle and Huon Pine. I finished it with Organoil (I think).
My better half put a favourite pot plant on the table and it grew there happily for about 6 years. When we sold up and moved we lifted the pot plant and bowl and discovered to our horror that at some stage the water bowl had overflowed and there was a filthy big round water stain in the timber (not the Huon Pine though). When I got my Shed (pictured at left :D) set up I began the process of removing the stain. I tried everything except the belt sander - an option that's not an option :cool:. Steel wool and metho, wet and dry with water and metho, Bleach (left overnight). I managed to get the stain to fade to about 50% thanks to the bleach, though any part of the chemical cocktail could have been responsible. I've considered routing the circle stain (about 200mm diameter) and inlaying Huon Pine or King Billy. Before I undertake this option is there anything else people can recommend for removing the water stain.
Ta! :confused:

[Gumby]

Absolutely no problem - put the pot plant back :D

[wombat47]

Liberon Enterprises (www.liberon.com.au) sells Wood Bleach -

"For removing dark stains caused by rust, alcohol, damp, ring marks, fruit etc., and lightening naturally dark wood or natural wood which has darkened through alkali stripping, staining or weathering."

I suppose any wood bleach would do the job.

[Shedhand]

Absolutely no problem - put the pot plant back :D

Brilliant Gumby..hadn't thought of that....Idiot :cool:

:D

[Shedhand]

Liberon Enterprises (www.liberon.com.au (http://www.liberon.com.au)) sells Wood Bleach -

"For removing dark stains caused by rust, alcohol, damp, ring marks, fruit etc., and lightening naturally dark wood or natural wood which has darkened through alkali stripping, staining or weathering."

I suppose any wood bleach would do the job.

Thanks Wombat...I'll buy some and give it a go.
Cheers

[Shedhand]

Ok Guys, 'ere 'tis,:)
Mixture:
250 grams of Oxalic Acid fully disolved in 2 litres of water.

--------Oxalic acid is one of the strongest organic acids. It is widely used in wood restorers and deck cleaners to dissolve the top layer of dried wood and expose a clean layer-----
NOTE: It is a poisonous substance its fumes can make you sick. Wear rubber gloves and mix the acid and water outdoors or in a fume hood.

Method:
Wet stained timber with cold water, then
Scrub affected area with a stiff bristled nylon brush (vigorously)
Leave 20 minutes then wash of with high pressure hose or something like a Karcher.
Repeat if necessary.
Leave timber to dry in open air.
Sand to a smooth finish.

I did this on a Tasmanian Oak table top in laid with Huon Pine and Myrtle. The mixture didn't affect any of the timbers or the glue holding it all together.

Hope this is useful.

PS. Got the Oxalic Acid (dry crystal form) at a 3D Paint Shop.

[Timber_finisher]

Many, many years ago I was gluing some mahogony veneer and weighed it down with some scap steel pieces. Some glue seeped though a join in the veneer and rusted the steel, staining the mahogony. My father (a chemist) gave me some Oxalic Acid crystals which totally removed the stain. I sanded and laquered the project and it looked perfect.

Disaster, the stain returned!

The message being, leave the job sit for a few days before refininshing, in case the stain returns. I may need more than one go to remove the satin permanently amd if you seal it - you're stuck with it! I made my mistake about 35 years ago and I still have it to remind me. It annoys me every time I see it.

[Shedhand]

Hmmm. i'll keep an eye on it. Thanks for the warning.
Did you wsh it down with a neutralising agent. If not the stain may have been dead wood because the oxalic acid actually removes a layer of timber which you can see when you finish the scrubbing. I ran the Random Orbital Sander over it when it was dry before refinishing..
Cheers


PS: The new stain was probably iron oxide in the timber. (Rust)

[Shedhand]

Here are the results of using Oxalic Acid (3 times) then 4 coats of China Wood Oil (2 days later) on the water stain. You can just see a little bit of stain at the top centre of the table top. Not a bad result really. I reckon I reduced the visual impact of the stain by 95%. The other closeup shots are just to show off my first attempt at inlaying other bits of timber. The small yellowish inserts are huon pine and the long narrow bits are myrtle. I made this hall table about 7 years ago and all I had was my Triton saw table and router. Originally sanded with a 1/4 sheet sander to 180 grit. This time sanded to 1200 grit.
Cheers:)
OOPs! forgot the pics. Herre they are.