Potassium Bichromate

[groeneaj]

Does anyone know where I can buy some Potassium Bichromate in Syndey? I want to use it to darken some Red Cedar - http://www.woodworkforums.com/f9/darkening-aussie-cedar-572/

I have tried my local chemist with no luck.

Just a quick question - when applying, do you apply it to a surface which is ready to be sanded? ie I have dressed up my timber. I would then apply the diluted Potassium Bichromate until I am happy with the colour. Then proceed to sand up to my desired grit?

Andy :)

[rightendup]

Potassium Bichromate or Dichromate could be found at a photographic supply house - used in color photography.
Sand to finish, apply a solution of Lye (drain cleaner) - about one tsp per liter distilled water and wire brush with the grain (brass brush) neutralize with white vinegar and water (1 tbl spoon per liter distilled water ( lye is very alkeline) .
When the wood is dry apply your Pot. Bich. ( 2 tsp per liter - for starters)
Always do a test.
I can vouch for the lye and vinegar recipes but you must do some tests with the PB strength.
Strongly recommend distilled water as any iron content in your water could really botch the job.
Pot Bich. is really good in brining out birds eyes in maple and also darkens the dark in the dark wood and leaves a varigated finish. Too strong and you get a decidedly yellow product.
If you can't find any, I'll send you some from State-side.
PM me.
Good luck