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Anti Corrosive Coatings for Plating Shops

2000

Dear Fellow Finishers,

Whats the best plating to apply to the following hardware we use inside plating shops :

1. Aluminium busbars.
2. Copper Busbars.
3. Nuts and Bolts around Chloride Zinc Tanks.
4. Hull Cell Clips.
5. Copper Pipes on :

   a) Nickel plating Tanks
   b) Chloride Zinc plating Tanks.

Thanks in advance

Khozem Vahaanwala
Saify Ind

Bengaluru, Karnataka, India

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That really depends on your budget and what other resources you have available.

Chrome plating the buss bars around nickel and high chloride tanks helps. There are buss bars made with a SS or a Ti case. these are really nice, but are not cheap.

A piece of hose has been used over round buss bars in lots of shops. Since it is split to go on, it comes off very easily if you need to move an anode. Tape has been used in lots of shops.

For nuts and bolts, plain old Vaseline works. I have used low melt plastics like that which is used to protect cutting tool edges. Liquid masking materials work well for some applications. It is however somewhat hard to get off. Plastisol works very very well, but is very hard to come off.

Never used it, but consider Saran wrap or shrink wrap. Secure it with tape or rubber bands or plastic wire ties if necessary.

James Watts
- Navarre, Florida
2000

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2000

Hi Khozem!

What James Watts said makes a lot of sense.

Regarding shrink wrap, try the local main electrical distributors. Electricians use a Polyethylene shrink wrap tubing to get a firm seal around buried electrical connectors.

For nuts and bolts here's a different idea. If you don't want to protect with a grease, sic. Vaseline, then try to use a nut that is lower on the galvanic series than the bolt, ie. a s.s. bolt and a mild steel nut. Why? Because preferentially the nut will eventually fail BUT, BUT, BUT it will never jam/freeze/rust in place and can always be unscrewed.

Another (highly unusual) idea is where there is a short run of rod/pipe to be protected. Get some ordinary PVC pipe which has an I.D. slightly smaller than the rod.

A). If it is very short you can heat up the PVC and press fit over the rod.

B). The other way is to leave the PVC pipe on a perforated plate above some PVC solvent for some hours.

The PVC will swell enormously as it absorbs the solvent. You slide this over the rod....and let it dry. Once all the solvent has evaporated you are back to a very tightly fitting rigid type l PVC. This process has been used on tool handles in the past. In retrospect maybe ABS might be more suitable as the ABS solvent, MEK / methyl ethyl ketone, really softens it up fast and ABS is fairly good in acids and alkalines and is far better on impact than PVC. Further, unlike any other plastic, you could make up a 'paste' of ABS (using solvent of course) and gap fill any holes in the material.

Works like a charm! Cheers!

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