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Dengue
26th August 2020, 03:21 PM
Hello, I want to brass plate some small steel screws and washers.
Can anyone please advise the best way to do this?
I am familiar with electrolysis, having used it for derusting steel
Hoping someone has had success with brass plating that they can share

BobL
26th August 2020, 08:21 PM
I've never done it (I do Zinc from raw chemicals) but here is a brass I looked at a few years ago - too expensive for me.

Brass Plating Kits | Caswell Australia (https://www.caswellplating.com.au/store/store.php/products/brass-plating-kits)

Make sure you avoid the cyanide based methods - too dangerous.

China
26th August 2020, 11:55 PM
Most companies no longer supply cyanide based plating chemicals to individuals only companies, if you only have a small amount take them to a plating company and they will put them through with another job and it will cost you less, otherwise go for the kit above.

Dengue
27th August 2020, 08:04 PM
Thanks BobL and China. That Caswell kit was way, way to expensive for me too. Will have to chase a plating shop, none in Townsville region unfortunately, and I am loathe to risk losing 100 yr old screws in the mail :(

BobL
27th August 2020, 09:32 PM
Thanks BobL and China. That Caswell kit was way, way to expensive for me too. Will have to chase a plating shop, none in Townsville region unfortunately, and I am loathe to risk losing 100 yr old screws in the mail :(

An alternative would be copper plate.

Start by delisting the screws (suggest citric acid dip) and then cleaning by boiling in sodium carbonate (Foot bath salts - $5 at Coles) for 15 minus.
From here handle with latex gloves and use clean container.s
Then boil in distilled water for 10 minutes
Make up a strong solution of copper sulphate )nurseries will have it) dissolved it until no more dissolves and decant off the liquid.
suspend screws in solution
The copper will auto plate out onto scrupulously clean steel should happen quickly depends on temp.

Remove screws from copper solution and wash in distilled water.
If you want them to stay bright sparky some clear metal lacquer on them.

Copper solution can be reused over an over.
Suggest trying this out on non-critical screws first.

russ57
27th August 2020, 10:55 PM
Last time I enquired about brass plating, I waa advised gold flashing would be cheaper
Apparently the toxicity of the chemicals is the issue.

havabeer69
28th August 2020, 01:35 AM
i remember watching a video a while back where a guy brass plates an axe. would have to watch again to see exactly how he does it but i don't remember it being anything fancy. Turns out its just heat the metal up and just rub the crap out of it with a wire brush on a drill


https://www.youtube.com/watch?v=3dARLlkeyZA

auscab
28th August 2020, 10:53 AM
What do you need the screws and washers for ?
Do you need the strength of steel and Brass for looks or protection from moisture ?
You can cover steel with Brass looking Bronze or For easier melting a mixture with more silver in it by Brazing with Gas and flux . I once made Bronze dome head Screws from steel flat heads doing this When I couldn’t find the right size for a job . A drop of Bronze on top and a saw cut Did it . Covering steel in the stuff isn’t a fine even coating though so a bit of leveling and buffing is needed .

China
28th August 2020, 02:20 PM
May be simpler to just just buy replacements Bronze & Brass Fasteners Pty. Ltd. - Australia (https://www.bronzeandbrassfasteners.com.au/)

Tinkicker
29th August 2020, 11:17 AM
The following comes from a background of an apprenticeship in Electroplating, a Craftman’s Certificate, a couple of Certificates in Industrial Chemistry and a few years experience in the industry.

Plating brass on steel is not an easy process. You cannot plate brass directly onto steel and expect good results, there are a few other steps in the process. The substrate that you are plating onto is iron based, and unless you can provide a very well ‘attached’ base layer, then all the other layers that you will ‘plate’ on top, will be at the mercy of the base layer. One small hole in the base layer and it will allow moisture in and oxidation will occur. This will result in the entire plated layer eventually lifting away. Not ideal. Also, as brass is an alloy of two or more base metals, getting the chemistry and the electropotential across the bath right is a pain. I hated looking after brass baths as they were notoriously difficult to get right and keep right….but I digress.

Steel was notoriously difficult to prepare, given the variances of the alloys in steel. There were different processes used, depending if you were conducting electroplating for either engineering purposes, or decorative purposes. I will leave the engineering processes out of the discussion as it appears from your post and the forum (Restoration) it is a decorative result that you wish to achieve. The engineering processes are also very $$$$$.

To achieve a good base substrate, we used to use a cyanide based copper solution. These are now out of favour due to the environmental constraints placed on the electroplating industry. You cannot use an acid solution due to galvanic displacement between the iron and copper. Without getting into a lecture on chemistry the following is a simple explanation.

Copper is considered to be more ‘noble’ than iron on the table of elements and therefore it will selectively ‘deposit’ onto lesser metals. (It’s a similar principle to using a zinc anode on a boat or outboard motor for protection). This ‘deposit’ is not the same as an electroplated deposit as the galvanic process uses an oxidation reaction to deposit the metal. As a result the layer is porous (at an atomic level) and weakly attached, something that you do not want on steel as explained above.

Trying to set something up at home, without some experience in electroplating, can be done, but there will be a lot of trial and error and $$ involved before you achieve the results that you want. Once you get the copper layer right, you will then need a flash of nickel over the copper (more $$) and then the brass layer (more $$).

As others have indicated, it will be a lot cheaper and a lot less messy to try and source replacement screws and washers in brass. If you need to use the originals, as it sounds like a restoration is taking place, then as China has indicated, find a plating shop that is already set up (they have spent the $$ and have the headaches and mess to deal with) and get them to put it through with another job.

Sorry to dampen your enthusiasm but these days, electroplating anything is not as easy as it once was.

Tinkicker