Zinc Plating

[Matt_Harrington]

I decided to re-plate a few parts yesterday and I thought I would yellow passivate the relevant carb parts. The results were poor and dull, so I tried blue passivate followed immediately followed by the yellow - and the results were fine.

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As you can see it turned out OK but I've probably done something you shouldn't!! (In fact I removed the old yellow passivate in the acid bath and quickly re-passivated  - again, probably a no no!  )

Anyone tried a water based lacquer on the passivate - supposedly allows it to last 10 times longer - I will research this....
Matt

[Terry Harlock]

Following with interest as hope to be getting a kit and doing some myself, seems quite the mine field the more I read, appears like heaps of trial and error and more trying!

[Matt_Harrington]

Terry, I am no expert but found it all to be straightforward.  The following bullet points may help:

1. Make sure all parts are cleaned well before starting
2. Prep surfaces as best as you can - remove as much crud as possible and file any burrs off etc. Smooth off if required. Remove as much rust as poss.
3. Degrease well after prep and then acid dip until you are happy.
4. Use a constant current power supply (they are not expensive). I roughly guess the surface area to be plated and then set the current accordingly.
5. Make sure various baths are to the correct(ish) temp - I use a fish tank heater for the plating solution and my ultrasonic tank for the degreaser.
6. Don't touch the passivate until fully dry.
7. I store all the liquids in 10 litre sealable tubs - ready for the next session!

If you have a large amount of nuts and bolts, then it is much easier sending them off to a platers - cheap(ish) and easy. Make sure they can 'tumble' the parts rather than wiring up as this makes the price low. (of course there are some parts that cant be tumbles!)

Matt

For me, it is great to be able to plate half a dozen parts whenever I want

[Matt_Harrington]

Zinc lacquers and sealer - I got this reply from a supplier:

Zinseal and The water based lacquer are very different products and should be used according to the application you require.
 
Both are technically a clear coating but the passivate sealer is used as a protective coating for passivate. It will remove colour from a colour passivate, so should be used on clear (blue) finishes.
 
The lacquer on the other hand is a thicker, harder finish but should not be used on threaded parts.


Matt