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Ted Mooney, P.E. RET
Pine Beach, NJ
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for Metal Finishing since 1989
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Removing Rust and Passivating a meat mincer
June 9, 2011
Hi there,
My name is Cameron and I live in New Zealand. I am really keen on making myself some homemade sausages so I purchased me a second hand stainless steel manual meat mincer.
This one at www.sausagemaker.com/6122222stainlesssteelmeatgrinder.aspx :
I am not sure what grade stainless steel this is, and I think it's possible the legs of the unit may be a different grade. I believe it to be grade 304 but am not 100 percent sure yet.
The problem is the unit came with some rust when I bought it, so I would like to remove the rust and passivate it to prevent any future issues. I am not entirely sure if this is the best way to solve this problem, so that's why I have come here to get expert advice if you would be so kind to share it with me.
I found a company close to me that does Pickling and passivation of stainless steel and also Electro polishing, I gave them a ring and was advised it would cost around $30NZD, not that much but I was thinking it may not give me the finish I am looking for.
In one or two of the photos it appears the legs of the unit may be cast iron that is tinned or plated? There is some slight pitting and it looks quite bad.
If I have missed anything please do not hesitate to ask me, I look forward to hearing your responses.
Cheers
Hobbyist - Auckland, New Zealand
Hi everyone, does anyone have any input? Thanks
Cameron Colyer- New Zealand
July 5, 2011
If it is indeed T304, it will polish nicely, and should resist corrosion quite well. Just be certain to clean it thoroughly when finished using. However from your photos, it looks like some parts are plain steel. Check them with a magnet, or have the electropolishing shop evaluate before electropolishing.
Jeffrey Holmes, CEF
Spartanburg, South Carolina
First of two simultaneous responses -- July 5, 2011
Second of two simultaneous responses -- July 5, 2011
Dear Cameron,
As to my knowledge these things are not made of stainless steel.
It might be Aluminium or Zamac or cast iron - all with or without a coating.
Personally I would clean it with with foodgrade abrasive and foodgrade oil. For example using crushed grains and passing these several times through your mixer, adding some olive oil at the end. The oil will prevent the mixer from rusting.
Kind regards,
Marc.
- Brugge, Belgium, Europe
July 8, 2011
Hi Marc and Jeffrey, I do know that it is indeed stainless steel, of which grade I am unsure about. The rust on the mincer at present is the aftermath of sitting in a cupboard for four years without oiling or proper storage. I am wanting to use a common green kitchen scourer to remove the rust and then passivate using a 10L bucket filled with distilled water and around 500 grams of common kitchen citric acid
⇦ this on
eBay
or
Amazon [affil links] . How effective would this be? And how could I improve my method?
Looking forward to hearing from both of you.
Thanks
- New Zealand
I'll take your word that it is indeed stainless steel. Based on that, it would rust in storage only if not scrupulously clean when put away. Cleaning with a green scrubby is not a bad idea, but never use steel wool such as Brillo - a good cleaning and thorough rinsing should be all that is necessary, however if you want to soak it in citric acid , no harm will be done.
Jeffrey Holmes, CEF
Spartanburg, South Carolina
July 8, 2011
July 12, 2011
Dear Cameron,
I agree with Jeffrey. You can do no harm with these operations.
Kind regards,
Marc.
- Brugge, Belgium, Europe
Thanks Marc and Jeffrey, I have one more question though, what would be a suitable amount of time for the citric acid bath for it to be effective? Or how would one go about inspecting it and making a decision when to stop?
Thanks
- New Zealand
July 14, 2011
You won't see anything happen while soaking in citric acid . Personally I don't think it's going to make much difference. 30 minutes should accomplish everything citric acid will do. Rinse, dry, and put away. It'll be fine.
Jeffrey Holmes, CEF
Spartanburg, South Carolina
July 15, 2011
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