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Mixing/storing Lacquer in a Stainless-Steel tank

Ok Here is my question, We are having a problem with lacquer in our plating shop,we had made for us a brand new stainless steel tank(actually 2 of them) We filled the both of them with a 40% mixture of lacquer and water. Now it worked fine for a few months,then we started getting this terrible smell from both tanks. We took a sample from each tank and sent them to an independent lab.....everything checked out good except there was a bacteria found in the lacquer,they had suggested using this stuff called Suraside-C it was basically a medicine for the lacquer. So we were pouring this in as to there recommendation,and it did not help one bit. Now I read somewhere that lacquer should never be put in a stainless steel tank,only Poly-Pro is recommended because the ammonia ⇦ this on eBay or Amazon [affil links] in lacquer inhibits the corrosion of the metal. If you could shed some light on this matter it would be greatly appreciated.

Brian Gaylets
Mckinney Products - Scranton, Pennsylvania, U.S.A.
2004

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2004

Brian,

Pardon my total ignorance but I always was under the impression that lacquers were NOT miscible in water.

But not being a plater, I just don't understand why you want to put PP in the tank? Maybe you can explain. After all, PP is a rigid material, prone to oxidizing attack, has a high coeff. of expansion but does possess some very good corrosion resistant features. ... and putting in a rigid thin wall PP liner calls for some expertize in 'making it last'. Why not a PP:FRP dual laminate?

Freeman Newton [deceased]
(It is our sad duty to advise that Freeman passed away
April 21, 2012. R.I.P. old friend).

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We cut our lacquer to 40% with water because straight lacquer is way too heavy for what we are plating, our baumé on the lacquer is appproximately 2.3. At 100% we get a very bad iridescence. We weren't gonna put Poly-Pro inside the tank, if stainless was not the best route to go we were going to just totally replace it with Poly-Pro or like you suggested have someone line the inside of the stainless tank. We have the 2 guys that do all our plating work (installing lines and so forth) and they are very good with all aspects as far as building and expanding plating lines. If you need more info I'll be more than happy to provide it for you and I thank you for the answer and any other help that you could provide me with.

Brian Gaylets
- Scranton, Pennsylvania, U.S.A.
2004

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2004

Brian,

More often than not, people never give enough info. So I wonder if you could please tell me

l. What are the size of your tanks?
2. What is the max. operating temperature?
3. What acids/alkalies are you using?

PVC would be nbg due to your lacquer ... but is it a TRUE lacquer? ... and not an aliphatic or a polar solvent perhaps?

Why just PP .... why not Pe ?

Freeman Newton [deceased]
(It is our sad duty to advise that Freeman passed away
April 21, 2012. R.I.P. old friend).

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This is great that you have this kind of knowledge,and I thank you for your help! The lacquer that we use is a Macdermid product called Aqualac EK it is a water soluble lacquer that we cut to 40% with water.The tank size is 734 gallon stainless steel tank,it is not lined with anything,just the raw steel. The lacquer we use at room temp. although the air temp. is always around 80-90 degrees in the shop(in other words it's not climate controlled) and we do filter the lacquer with a double tube system and we use 5 micron filter tubes. What we use the lacquer for is to cover industrial door hinges that are run through the hole cleaning cycle(soak,electro,cathodic acid,stag acid) of course these go through the water rinse cycle,the they are Ni plated then over top the Ni they are plated with Tri-Chrome(dull finish) and then rinsed off in 1 Cr dragout,then 2 cold water rinses,then finally a hot water rinse then about a 4 minute air dry time and finally into the lacquer. Again I thank you for all your help and knowledge!

Brian Gaylets
McKinney Products - Scranton, Pennsylvania, U.S.A.
2004

Brian,

Last thing ... ever heard (but I'm sure you have) of rotationally moulded Pe tanks?

In Canada the largest rectangular sized one is 500 gallons. That is 500 IMPERIAL gallons ! Max. recommended continuous temperature is ll5 degr. F but any large rectangular ones would probably need some external bracing, ie. wood.

Something of interest is that, for a small extra, you can get the manufacturer to 'add' more powder and hence build up the wall thickness to a max. of 1/2". This is of particular importance where oxidizers (nitrics etc) are concerned. Have a glance at the archives at # 7132 which may perhaps be of some interest.

The main difference between PP and Pe is that PP is much stiffer and can take a higher temperature ... both are weldable but not to each other ... both will (slowly) burn and drip. Pe excels on impact. However, PVC is my favourite thermoplastic.

Freeman Newton [deceased]
(It is our sad duty to advise that Freeman passed away
April 21, 2012. R.I.P. old friend).
2004

Once again I Thank You very much! I believe that you have set me in the right direction with my little dilemma! Once again thanks for all the tech. support and help. I appreciate it and not to metion my fellow workers! If your ever in the area of Pennsylvaia maybe we could set up a tour of our plating facility, love to have ya!

Brian Gaylets
- Scranton, Pennsylvania,U.S.A.
2004

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2004

That was a bloody nice invite, Brian, merci buckets !

This, over the last 3 or so years, is only the 2nd time that someone has dared to invite me to their premises, the other one came from Singapore.

Mind you, I'd love to come if you paid the airfare (We finishing.com responders only travel first class, in case you didn't know) and would expect at least a R.R. or a Jag to pick us up (no cheap BMW's, please).

Seriously, thank you for the invite ... not many people come back to thank fin.com experts, which I ain't, so this is truly appreciated on behalf of all, well most, fin.com responders.

Freeman Newton [deceased]
(It is our sad duty to advise that Freeman passed away
April 21, 2012. R.I.P. old friend).

Once again I really do thank you and that invite is always open, as for the first class accommodations....well I only handle the plating & waste treatment problems for my company......anyway.....Thought you might find this interesting, we finally got a sample out to an independent microbiologist, and we got the report back...we had 10 million ppm of some kind of bacteria in the lacquer(WOW!) and he had recommended keep putting this Suricide-P (bacteria killer) in the lacquer and he also sent us this mixture of Hex-Chrome he had made up to pour in and so far we have had good luck with this...no smell so far! (good thing this had worked, My a$$ was on the line here!) But we are definitely taking your advice and looking into a new tank.....Hey if they can't believe an expert who can they believe!? Hey again thanks for all the help it really was appreciated!

Brian Gaylets
McKinney Products(Assa Abloy) - Scranton, Pennsylvania, U.S.A.
2004