Ultrasonic Cleaning of Stainless, how to and re-passivation?

[Apex]

I have all standing rigging off for the winter, and wanted to clean up and re-passivate much of that rigging, including turnbuckles and mast plates. What should be used for chemicals in the ultrasonic cleaner, and then how to re-passivate?

I will continue to research, but thought it would be good to post this topic for sharing. Who has the metallurgic background and experience? I definitely don't want to create any long term issues.

 

[dlochner]

The turnbuckles may not be stainless, they are often chrome plated bronze.

 

[thinwater]

The turnbuckles may not be stainless, they are often chrome plated bronze.

Correct. Turnbuckles are virtually never stainless, except on dingies. Stainless is very prone to galling when tightened under load.

A 1 hour soak in 10-15% citric acid at about 150F is a good passivization method. Many variations. Longer times can replace heat, higher concentrations don't help.

 

[Apex]

The turnbuckles may not be stainless, they are often chrome plated bronze.

Great point, mine definitely aren't.....
....any issue with giving them the same wash treatment?

Here is what I found so far:
How To Passivate Stainless Steel Parts
Process 1 for Austenitic stainless
Cleaner/Degreaser
Water Rinse
Passivate per Fig.4 (10% by WEIGHT citric acid, 150F, 30min)
Water Rinse
Dry

 

[Apex]

Correct. Turnbuckles are virtually never stainless, except on dingies. Stainless is very prone to galling when tightened under load.

A 1 hour soak in 10-15% citric acid at about 150F is a good passivization method. Many variations. Longer times can replace heat, higher concentrations don't help.

Thanks Thin! Exactly what I found with the Googles.....My ultrasonic cleaner has heat, so 150F it is for 30min...

 

[jssailem]

Thanks Thin! Exactly what I found with the Googles.....My ultrasonic cleaner has heat, so 150F it is for 30min...

On brass I have used a mild soap water solution in an ultrasonic cleaner. Cleans the grime and dirt away to bare metal.

 

[thinwater]

Don't ultrasonic clean for more than a few minutes. That can do damamge on its own and is not needed or helpful. Just a few minutes. For SURE don't unlrasonic clean the turnbuckles, unless you want to risk pealing the chrome or loosening inserts.

I have an ultrasonic cleaner, but most I used it to torture test and destroy certain parts as part of a QC process. Like power washers, they should be used with extreme restraint. I'm not a big fan for cleaning.