Ultrasonic cleaning problem

[Jschara]

I made a DIY ultra sonic cleaner to wash motorcycle parts. I had already had the engine cases bead blasted so I wanted to make sure all the media was throughly washed out of the cases. I had washed everything twice house hold detergent. Wanting to make sure, I put a case in my home made washer with warm water only.

Ran it for approximately 20 minutes. WhenI I took the case out it had discolored in several places. It no longer looked good.

Any ideas why it discolored?

 

[M.Jay]

What exactly did you use? Alkaline cleaners will damage Aluminium.

 

[Rinspeed]

What exactly is a DIY ultra sonic cleaner.

 

[cgrutt]

Guessing alkalinity in detergent caused oxidation. Try soaking inconspicuous area in vinegar and lightly scrubbing see if it restores color.

 

[Jschara]

No cleaners. Just warm water.

What exactly did you use? Alkaline cleaners will damage Aluminium.

 

[Jschara]

What exactly is a DIY ultra sonic cleaner.

Do It Yourself. Home made.

 

[PCustoms]

I had washed everything twice house hold detergent.

What detergent?

 

[Jschara]

What detergent?

Dawn detergent.

 

[bluedog225]

Do It Yourself. Home made.

I’m curious how you put that together. Might be relevant.

 

[LopezBart]

Dawn detergent.

https://msdsdigital.com/system/files/Dawn_Professional_Dish_Detergent_0.pdf

reports the pH at mildly alkaline - 8.7 - 9.3

A pH above 9 will cause aluminum corrosion, as can the presence of any copper or brass in contact with the cleaning solution.