Home /
T.O.C.
FAQs
 
Good
Books
Ref.
Libr.
Advertise
Here
Help
Wanted
Current
Q&A's
Search 🔍
the Site

World's #1 finishing resource since 1989
No login needed: Chime right in

topic 46659

Zinc flake coating questions

Current question and answers:

TUTORIAL FOR NEWBIES:
S442 is a Ford specification for zinc-rich dip-spin coatings

January 25, 2021

Q. I want to calculate the cost of S442 coating. What variables should be used and the formula?

Tarun Gohil
- Burlington New Jersey
^- Reply to this post -^

adv.: Dip-spin Coating Services
saify ind banner


January 2021

A. Hi Tarun. To the best of my knowledge there are no cost estimating books for plating & metal finishing like there are in the construction industries for example; but there have been published papers on the subject like:

polynet.dk/ingpro/surface/elecomk.htm

If possible, the best approach is often to ask a shop which offers the specific coating you are looking for what factors affect their pricing. We've attached your inquiry to a thread on zinc-rich dip-spin coatings which may give you some insights, and we have threads on cost estimating for various finishes if you search the site for "cost of [specific finish]".

Luck & Regards,

pic of Ted Mooney
Ted Mooney, P.E. RET
Aloha -- an idea worth spreading
finishing.com - Pine Beach, New Jersey


February 9, 2021

A. Ford S 442 is a specification for a zinc-rich coating, applied either as a dip-spin coating or a dip-drain coating. I would interpret 'cost' as what it costs to do this process - which would include many direct costs and usually an allocation of indirect costs. Those who apply this paint from approved paint suppliers usually have a reasonably good handle on these costs. I would interpret 'price' (which hasn't been brought up, but I'm mentioning it anyway) as what approved applicators charge for this finishing process. RFQ's to approved applicators are the most viable source for this information. You can buy the standard and a list of approved suppliers online. I've mentioned 'approved' five times, just in case someone might think otherwise.

tom_rochester
Tom Rochester
Plating Systems & Technologies, Inc.  
supporting advertiser
Jackson, Michigan, USA
plating systems & technologies banner ad




Previous closely related Q&A's starting in:

Need Dacromet without Chrome-6

2004

Q. We currently use Dacromet coating on socket screws and large bolts. Our customer has asked that we change from Dacromet to a non hexavalent (?) finish. We need to retain all the other qualities of Dacromet, e.g., Salt spray resistance, suitability for threaded components, etc.

Please advise a suitable treatment.

John McCarthy
distributor - Bristol, United Kingdom
^- Reply to this post -^


2004

A. Hi Nick, hi John. The manufacturer of Dacromet offers a chrome-free system called Geomet. I can't say to what measure the qualities are maintained without hexavalent chrome, but trying is doubtless the goal. There are, of course, several other brands of zinc-rich dip/spin coatings available, and Tom Rochester offered a great list at

web.archive.org/web/20141217004049/http://dipspincoatings.com/

Good luck.

Ted Mooney, finishing.com Teds signature
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey


October 7, 2018

A. I would like to clarify here: There is difference between Dacromet and Geomet. Dacromet contains Chromium and its SST life is less than Geomet coatings.
But both the coatings are well known and accepted by many industries. And it's a trademark coating.
So my recommendation to people: choose Eco Friendly coatings- Geomet and there are a wide range of Top Coat varieties which will help you to increase Salt Spray Test And COF Range.
I am not advertising here; it's just an opinion to people.
I had worked so far in this field so I know about this.

neeraj_rao
Neeraj Rao NKR
Social Worker - New Delhi India


thumbs up sign Thanks Neeraj. Readers are reminded that there are a number of companies offering dip-spin coating processes, as well as competing technologies like sherardizing, mechanical plating, and zinc alloy platings with eco-friendly non-hexavalent conversion coatings.

Luck & Regards,

pic of Ted Mooney
Ted Mooney, P.E. RET
Aloha -- an idea worth spreading
finishing.com - Pine Beach, New Jersey



To minimize search efforts and to offer multiple viewpoints, we combined previously separate threads onto this page. Please forgive any resultant repetition, failures of chronological order, or what may look like readers disrespecting previous responses -- those other responses may not have been on the page at the time :-)



Are Dacromizing and Dacromet 320 the same?

2005

Q. Dear Sir,

For a screw we use we specify Dacromet 320 as surface treatment. The information we have about that treatment is no red rust in a salt spray test according to ASTM B117 [affil. link to spec at Techstreet] within 500 hrs.

I found out that, due to a supplier change, the treatment is changed to Dacromizing instead of Dacromet 320. For Dacromizing I can find information on the internet that it has "only" 240 hrs. resistance.

Can someone tell me if Dacromizing is exactly the same as Dacromet 320 and what is the correct salt spray resistance 240 hours or 500?

Thanks in advance for your reaction.

Bert Volkers
Industrial door producer - Noord Scharwoude, NH, The Netherlands
^- Reply to this post -^


2005

A. Dacromet 320 is one product from Metal Coatings International, the original developer of this coating. Dacromizing is a generic word to mean coating with a Dacromet product. It is not a suitable specification for a finished product. Corrosion resistance will depend on the coating thickness. In order to achieve 500 hours of salt spray resistance, the coating thickness must be at least 5 micrometers for Dacromet 320. You should contact Metal Coatings directly if you need additional information, or visit their website.

Toby Padfield
Automotive module supplier - Michigan


2005

thumbs up sign Sorry, I spelled the word completely wrong. I should have written Dacrotizing instead of Dacromizing. I think the question is answered now.

I found now that Dacrotizing is the process of applying Dacromet 320 to the surface. One web site is saying Dacrotizing = Dacromet 320 which gives min. 500 hrs in Salt Spray Test) and another site is saying Dacrotized coating gives 500 hrs in SST. So I now have some back up that with Dacrotizing we still have the same corrosion resistance.

Bert Volkers [returning]
- Noord Scharwoude, (NL)



To minimize search efforts and to offer multiple viewpoints, we combined previously separate threads onto this page. Please forgive any resultant repetition, failures of chronological order, or what may look like readers disrespecting previous responses -- those other responses may not have been on the page at the time :-)



Dacro Finishing

2005

Q. I have come across a door striker ( which is the mating part of the car door latch )with a special type of finish having a dull grey colour. On enquiry I was told that it was zinc plated with dacro finish.

Can somebody tell me what this surface finish is? And any more details like process, cost, etc.

Regards

V.Chandrasekhar
Automotive Component - Bangalore, Karnataka, India
^- Reply to this post -^


2005

A. Dear Sir,

Silver grey coloured coating is from Dacromet. The same type of coating is available from Delta Tone (Doerken, Germany) It is applied by dip spin technique. Process cost would be Rs. 20 per kg. These kind of coatings have Chrome free resins and are patented too. It is approved by leading automobile manufacturers. Different top coats applied on this kind of coating give dry film lubricity. The total coating thickness could be 10 or 12 micron only. It's called Microcoat corrosion protection system with dry film lubricity.

kalyan dhakane
Kalyan Dhakane
Mumbai, India



To minimize search efforts and to offer multiple viewpoints, we combined previously separate threads onto this page. Please forgive any resultant repetition, failures of chronological order, or what may look like readers disrespecting previous responses -- those other responses may not have been on the page at the time :-)



Zinc flake coating questions

2007

Q. Hi. This is Pavan. I am from central India and are manufacturing roofing bolts. Presently we are zinc electroplating the roofing bolts and it costs me about 100$ per M.T. (on Job work basis). I am reading articles about zinc flake coating on the NET. Can I get suggestions on setting up a zinc flake coating shop. My production is about one M.T. per day. I would also like to have costing details. Does this zinc flake coating cost much more than zinc electroplating?

RFQ: I would also be interested in addresses and details of suppliers of machinery required for setting up a zinc flake coating shop.

Karnatakam Pavan Kumar
buyer - Hydrabad, Andhraprades, India
^- Reply to this post -^


2007

A. Hi, Pavan. You may be referring to mechanical plating with zinc? In this approach, zinc flakes and tiny glass balls are tumbled with the parts; the balls drive the flakes onto the parts under very high pressure.

adv.
If so, Plating Systems and Technologies [a finishing.com supporting advertiser] can help you.

Or you might be referring to dip-spin coating where a zinc-rich "paint" is applied. There are several manufacturers of these dip-spin coatings.

As a rule of thumb: the more zinc, the more expensive, and the more corrosion resistant. So, in general, mechanical plating and dip-spin coating will cost more than electroplating but deliver greater corrosion resistance. One reason you see so much zinc electroplating on fasteners is that in the general case there is no other way to apply zinc or other cathodic protection coatings which matches its low cost.

Ted Mooney, finishing.com Teds signature
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey


2007

A. Alternative zinc coatings can indeed save money over electroplating. Mechanical galvanizing would give you the most corrosion protection but mechanical plating would be a bit cheaper. I don't think a dip spin coating would be thick enough for your application.

I would go with mechanical galv but specify zinc in flake form so that thread fit is optimal.

Jeffrey McAnally
- San Diego, California, USA


2007

A. Zinc flake coating sold under the brands Zintek /Dacro / Geomet / Doerken are done by dip spin method and when done properly with a sealing lacquer give 1000 hours of salt spray test.

These coatings are very successfully done on fasteners.

Gurvin Singh
Coatec India
supporting advertiser
Mohali, Punjab, India
coatec india


2007

thumbs up signThanks Jeffrey, thanks Gurvin. I appreciate the input, and agree that the corrosion resistance of mechanical galvanizing and zinc rich coatings will exceed that of zinc electroplating, but I strongly doubt that any of these technologies will not exceed Karnatakam's cost of 4-1/2 cents a pound ($100/MT).

Regards,

Ted Mooney, finishing.com Teds signature
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey


2007

A. Dear Mr. Pavan Kumar,

adv.
Our firm can do both mechanical zinc or Dacromet coating for you.

Mechanical zinc will cost four times your present cost, and zinc flake will cost 8 times your present plating cost.

Khozem Vahaanwala
Khozem Vahaanwala
Saify Ind
supporting advertiser
Bengaluru, Karnataka, India
saify logo


July 18, 2014

A. The cost of Indian made Zinc Flake coatings is much lower, also you can get a dip-spin machine for your output at very reasonable cost, fully automatic.

Abhay Bhagli
- Pune, Maharashtra , India



Cost of zinc-rich dip spin coating vs. zinc electroplating

ACRONYMS:
BIW = The Body In White' stage in automobile manufacturing

February 27, 2015 -- this entry appended to this thread by editor in lieu of spawning a duplicative thread

Q. Hello All,

We are working on development of a fuel tank. The fastener used to hold it on to BIW is to be changed from zinc white trivalent coating to zinc flake coating to increase the corrosion resistance.

My query is actually what is the difference between both coatings technically and how much would be the cost impact between the two.

M6 Fastener, with Spring washer - Hexagonal type head

Thanks in advance

BALAJI SATHASIVAM
- BANGALORE,KARNATAKA & INDIA
^- Reply to this post -^


March 2015

A. Hi Balaji. Zinc-rich flake coatings are applied something like paint, with a dip-spin machine. Generally they are quite a bit thicker than zinc electroplating. Khozem's response to the previous question was from several years ago and for a somewhat different component. But I believe the thrust of it, that the cost of the coating is roughly proportional to its thickness. You might ask him for a quote. Good luck.

Regards,

pic of Ted Mooney
Ted Mooney, P.E. RET
Aloha -- an idea worth spreading
finishing.com - Pine Beach, New Jersey

Q, A, or Comment on THIS thread SEARCH for Threads about ... My Topic Not Found: Start NEW Thread

Disclaimer: It's not possible to fully diagnose a finishing problem or the hazards of an operation via these pages. All information presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. The internet is largely anonymous & unvetted; some names may be fictitious and some recommendations might be harmful.

If you are seeking a product or service related to metal finishing, please check these Directories:

 
Jobshops
Capital
Equipment
Chemicals &
Consumables
Consult'g, Train'g
& Software


About/Contact    -    Privacy Policy    -    ©1995-2021 finishing.com, Pine Beach, New Jersey, USA