Jump to content

DIY zinc plating / coating / sheradising - anyone done it?


Recommended Posts

Per the title really, I've got a couple of steel bits that I'd quite like to be protected from corrosion, and paint isn't the ideal option.

I know you can get kits to do zinc passivating, would love to hear anyone's experience with those or indeed any other ways of getting a really good bit of zinc onto a lump of steel.

Link to comment
Share on other sites

I have!

You need to get the surface really clean - I used a jetwash, grit blasting adaptors which took the rusty thing to gleaming, shiny metal.

In the real world, they pickle the metal parts in something that really cleans the surface - don't know quite what though.

Then I just used a lump of Zinc and battery acid as the electrolyte.  I used a variable voltage power supply, negative connected ot the part you want to coat - then crank up the voltage until it starts bubbling!  Bubbling is probably over-doing it.

It took a long time to get a decent thickness of zinc on the surface - but it worked just fine.  I remember just leaving it over night & using a digital micrometer to measure the increase in thickness.

The passivate is just a protective coating, dipped.  Not having real passivate, I sprayed it with laquer - which served the same prupose pretty well.  It stayed shiny for a long time!

  • Like 1
Link to comment
Share on other sites

Would it be possible to make a tiny galvanising bath? I am not quite sure of the temperature to melt zinc/lead mix, but with a small bath it may be possible. 

I know people that cast bullet heads and that is lead or a mix, so melting should be possible.  The issue with this is moisture on any parts that you dip as when it turns to steam it "explodes" and creates lots of flying very hot bits that you really don't want to be near. I think with precautions and lots of common sense it may be possible. 

Also, if you make your own galv, you can add a bit more lead so it's the better stuff that used to be produced before the environmental issues became more prevalent  - even though better galv means a longer life for the part.

Link to comment
Share on other sites

I think sherardizing is not so easy. There is some one on the series one club forum who has apparently done it. Apparently you put your parts + zinc powder into a rotating drum, purge with an inert gas, then heat the whole lot to ~ 400C while rotating the drum.

Try 'Electro plating at home' as search term in u tube - you get Geoffrey Coker's home plating video - 2 million + views... Looks easier than trying to sherardize!

Link to comment
Share on other sites

BZP without an overcoat of something is not worth the effort in my opinion. Just look at the BZP bolts in your garage. They’ve probably already started to corrode before seeing any real corrosive elements like road salt.

If you can get them hot dipped it would be worth every penny I think.

Link to comment
Share on other sites

What about Geomet coating ? It is applied by cold immersion and is water based, but I dont know how its done , but is the finish used on most automotive nuts and bolts.

I dont even know if its possible to buy it, but there may be companies who will do it.

Link to comment
Share on other sites

  • 4 weeks later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We use cookies to ensure you get the best experience. By using our website you agree to our Cookie Policy