Its an anodic ( as in anode ) process.
generally its done with sulphurice acid and an electrical current.
battery acid diluted with water 50/50 is the correct consistency.
you need a variable current source and a voltage of 12v nominal.
so a big battery charger and a variac is what I have used.
the item is connected to the positive lead ( anode ) and a series of negative plates circle the item to ensure an even current transfer.
google home anodising to find the current per Sq in. .
but almost any current will work eventually tho the correct current will see it done in 15-30 minutes.
the ali must be cleaned spotless using caustic solution.
depending on the actual ali it may need desmutting with another chemical and
rinsed spotless with pure water.
the ali will trun a slight yeloow colour when the anodising has taken place.
at this time you have an anodised item with open pores.
now you can colour it using a number of dyes.
clothing dye works well
inkjet ink works well
you can buy special purpose dyes from on-line suppliers.
soak the ali in the dye till it takes the colour.
place in boiling water to set it.
simples.:devious
generally its done with sulphurice acid and an electrical current.
battery acid diluted with water 50/50 is the correct consistency.
you need a variable current source and a voltage of 12v nominal.
so a big battery charger and a variac is what I have used.
the item is connected to the positive lead ( anode ) and a series of negative plates circle the item to ensure an even current transfer.
google home anodising to find the current per Sq in. .
but almost any current will work eventually tho the correct current will see it done in 15-30 minutes.
the ali must be cleaned spotless using caustic solution.
depending on the actual ali it may need desmutting with another chemical and
rinsed spotless with pure water.
the ali will trun a slight yeloow colour when the anodising has taken place.
at this time you have an anodised item with open pores.
now you can colour it using a number of dyes.
clothing dye works well
inkjet ink works well
you can buy special purpose dyes from on-line suppliers.
soak the ali in the dye till it takes the colour.
place in boiling water to set it.
simples.:devious