very simple and fast, I just removed the anodizing in the following way.
Needed
Bostik glue or Rubber cement - Pure sodium hydroxide flakes
For your safety, thick, solvent-resistant rubber gloves, protective glasses and an open environment to avoid inhalations as the sodium hydroxide dissolved in water is highly corrosive and can cause dangerous and serious burns to the skin and parts of the body.
Method
After cleaning the cups with soap and water and rinsing and drying them, mount them on a threaded rod the size of the axis, at this point drip or splash them with Bostik glue or Rubber cemen waiting for it to dry.
At this point prepare a possibly glass container (like a glass) with water at room temperature and dissolve a spoonful of hydroxide flakes, do it very gently and add the flakes to the water, never the other way round! this is to avoid dangerous splashes, when everything is dissolved (and you will also notice a significant increase in temperature) immerse the cups one at a time ⌠in the unprotected parts the anodizing micropores will open letting the dye come out ⌠everything happens in a few seconds at this point remove them and rinse them with plenty of running water.
Finally, remove the layer of glue and youâre done.
I recommend, maximum attention with sodium hydroxide, it is really dangerous!
The only drawback, between the anodized and raw parts, to feel a very slight step of a few hundredths of a millimeter, this will lead to an imperfect functionality towards the grind-tricks.
Some photos I took at the time:
thanks for the important clarification!
I did not know the acronym in English, in Italian it is "DPI (dispositivi di protezione individuale) -> PPE (personal protective equipment)
No, also because a whole life is not enough to consume an anodization in that way!
The Skyline was a sort of guinea pig for testing, I chose him precisely because he had some dents that I didnât like to see.
It was an âevolutionary processâ, first I partially decolored it, then I also tried to do âacid washesâ always using sodium hydroxide and I must say that the aesthetic result was not bad ⌠but for some reason (perhaps precisely because I really like finger-grinds, I donât remember) in the end I decided to do decoloring all the catch-zone and polish it in a mirror finishâŚ
This is what happened âŚ
sodium hydroxide â returns sodium (Na) and releases oxygen and hydrogen gas (technically called the dissolution process ⌠the heat that is generated is due to the breakdown of the molecular bonds), this is the chemical formula of this process:
NaOH â> (Na +) + (OH-)
so remain all natural and inert elements ⌠maybe with traces of yoyo color ⌠which I hope is a natural pigment ⌠but I canât know.
damn, this is so cool. i understand how stripping works, but how did you do that acid wash? did you just splash the sodium hydroxide on in patterns and then got them off before they âdissolvedâ the ano too much? would love to hear more detail!
Exactly, I dropped drops of hydroxide solution on the surface and rinsed under running water in 2-4 seconds (time depends on the greater or lesser corrosion).
Hahaha you will be surprised to hear that some competitorsâ yoyos are played so much the ano is completely gone. I think the one I saw was a 3A playerâs first ever unresponsive yoyo that he started 3A on. Itâs quite insane.
that is really cool. if you were ever to do it in the near future, please video it! i would learn so much from it. have been doing some of my own small ano projects but never got into acid washes!
Sorry, I only now remembered this thing while looking for old things on youtube âŚ
The day I changed the yoyoâs aesthetic at the start of this discussion, I met with Riccardo to show him and⌠this video was born.
One of the few where I am present âŚ
(the title explains the process )
