Prepare well for degreasing and polishing.
Brush after drying.
Spread with a tampon on the part thus prepared, uniformly and without excess.
After 3 to 8 hours, submerge in boiling water (rainwater) for 15 minutes.
Card out the oxide that has formed (use fine steel wool).
Repeat the operation 7 to 8 times.
In the last rinsing bath, add a few pinches of crystals (St Marc laundry type).
Warm with encaustic or linseed oil.
Rub cold with a flannel.
This work must be done in a not very hot place and with sufficient humidity, like that of a wine cellar.
The fast magnetic super tan product must not be subjected to strong heat, it must be stored under these same conditions.
If the process is having trouble starting, run a little nitric acid (diluted 1 or 2% in water) on your tan.
(Attention, do not forget to plug the ends of the barrel so that nothing does not enter it)
Tanning operations can be suspended at any stage exclusively after one of the rinsing boiling baths.
To obtain an even brighter black (jet black), treat with Finibronze after leaving the last bath.
Dangerous, respect precautions
Download here the SDS