It''s a lot of work to do the job right, but here''s how I did mine.
Use TSP to clean the teak. This is Tri sodium Phosphate, not the product sold as "TSP". The TSP will bring the oil out of the wood with a little scrubing with a medium bristle brush. Scrub across the wood grain or at a 45 degree angle to avoid scrubbing out the softer wood found in the grain. Wipe off the gunk and rinse the wood with water and let dry.
If you want it lighten it more, use Oxalic Acid solution. Apply it and let sit for 10 to 20 minutes then rinse with a solution of Borax to neutalize the acid. This should lighten the teak to a nice golden brown.
To apply the solutions sparingly, I used a small sponge dipped in the solution (wear gloves!) If you don''t squeeze the sponge too hard you can control the amount of liquid actually being applied to the wood. It''s a good idea to have plastic sheeting below the work area and maybe some old towels to soak up the liquid and gunk.
The oil darkens because it oxidizes with age. As mentioned earlier, some oil may be better than others. Personally, I like varnish
, as it is a permanent finish that makes your boat look like a yacht! Lots of work, but if you take pride in your boat, it is very rewarding to go the extra mile.
As I recall, I used about 1/4 cup of TSP to a gallon of water. two or three tablespoons of oxalic acid to a quart. If you aren''t getting results add a little more. If things are happening pretty fast add a little water.
Hope this helps!