Stamped brass oil removal.

[Lplates]

Hi team,
Long time no post!
Business is going great but once again I’m coming to my fellow PM team for some advice. We are stamping our own brass / copper parts now at a furious rate, however the stamping oil cleaning is a bit of an issue.

Anyone have any advice on the best way to bulk remove it without damaging the copper component? So no acids or alkaline.

1: We are going to try a simple detergent wet tumble then spin dry.

2: Detetrrgent tumble, rinse, metho or acetone bath to dry quickly.

3: Or dunk them in white spirit, tumble off excess then wash in detergent and water then tumble to get water out then dry.

I’m worried that if we dunk heaps in white spirit it will just saturate with oil pretty fast. Anyone else got any ideas, or does the oil float to the surface in white spirit so you can skim it?

Since part weight is critical (+/- 0.006 grams) I have found using acid washes problematic as it attacks the parts and leaves variance. If I could get the bulk oil off maybe a bit of acid in the wash for 5 minutes MIGHT be ok. Have to try.

Hope you guys can help me with a process. Thanks!

 

[Limy Sami]

What about a dish washing machine? ..........or the detergent, they have a wide variety of cleaning agents''

Just a thought.

 

[Lplates]

What about a dish washing machine? ..........or the detergent, they have a wide variety of cleaning agents''

Just a thought.

Very interesting idea!!

 

[Joe Gwinn]

How big are the parts to be cleaned. How complicated are their shapes?

Alcojet (for dishwashers) and Alconox (for hand washing) will botb work on copper and zinc, if rinsed promptly. I'd call Alconox company and ask for their advice.

https://www.alconox.com/product/alconox/

Another option would be an ultrasonic cleaned with 10% isopropyl alcohol in water.

 

[Lplates]

The parts are essentially bullet jackets.
So being small cups they will
Have oil from stamping on the inside. We are sure we need to tumble wash them so a regular washing machine on a hot cycle with plain dish detergent is a possibility.

We have also considered detergent washing in big buckets then into a cement mixer with a final hot water/detergent mix then rinse.

We figure they will need to tumble to get the water and detergent in and oil
Out. Thoughts on cement mixer on slow turn?

 

[Joe Gwinn]

The parts are essentially bullet jackets.

Length by diameter? Wall thickness?

So being small cups they will
Have oil from stamping on the inside. We are sure we need to tumble wash them so a regular washing machine on a hot cycle with plain dish detergent is a possibility.

A phosphate containing dish-washing detergent could work.

As the little cups come out of the drawing machine, are they oriented? Why not send them through a station that cleans the inside with a pressurized jet of hot water with detergent, like a bottle cleaner?

We have also considered detergent washing in big buckets then into a cement mixer with a final hot water/detergent mix then rinse.

We figure they will need to tumble to get the water and detergent in and oil Out.

This actually sounds like a good application for an ultrasonic cleaner. There are Alconox detergents for that, or just use isopropyl alcohol in water.

Thoughts on cement mixer on slow turn?

I'd be afraid that the little cups would end up too dented to be used.

 

[Limy Sami]

I've just remembered something

We're talking <>50 years ago, but one place I knew of, after a thorough drain, they vibrated machined copper and bronze parts out of the camautos in pine sawdust, before a final rinse in Tric (which I know is bad - but you get my drift)

 

[snowman]

ultrasonic with detergent

you want to keep your wash volumes to a minimum as it's likely going to be hazardous waste

 

[tdmidget]

Acetone and all alcohols are polar solvents and very limited ability to dissolve oils. All they have going for them is ability to wash off with water. Any kind of tumbling will leave marks. If they are indeed bullet jackets then the subsequent swaging op will likely remove these marks. If not then mass produced scrap. If you can orient them so as to drain, vapor degreasing will do a great job. expensive and hazardous agents involved. I guess you are realizing why you have this job. At least to start I would go with the ultrasonic and appropriate detergent.

 

[surplusjohn]

I was going to suggest saw dust also. a particular type of granular saw dust was used for cleaning printing plates, and printing ink is nasty stuff. my guess a hardwood. that provided some scrubbing action. point being different sawdust will give different results.

 

[GregSY]

.006 gram? Not only is that impossible to weigh, it's also impossible for science and math combined to even define.

 

[snowman]

6 mg is relatively easy to weigh.

My analytical balance reads to 0.01 mg and is repeatable at 0.04 mg and holds linearity at 0.12 mg throughout the 205 g range. Used cost right now is only around $2,000.