Palladium Tank Plating Solution

Preparing the surface for electroplating - creating a water break-free surface

Good surface preparation is one of the most important steps in successful electroplating. In fact, many plating problems occur because the metal surface hasn't been cleaned or prepared properly.

Before you start plating, your aim is to achieve a water break-free surface. This gives your plating solution the best possible chance of producing a sound, well-adhered finish.

The following guidance applies to pen, brush and tank electroplating.

What Is a Water Break-Free Surface?

A water break-free surface is a metal surface that’s completely clean and free from grease, oil and other contamination.

You can check this by holding your item under gently running water.

If the water flows evenly across the surface without forming droplets or pulling away into patches, you’ve achieved a water break-free surface.

However, if the water gathers into droplets or breaks apart, contamination may still be present. You’ll need to repeat the cleaning process before plating.

The photograph of the copper sheet above shows the difference.

On the top half of the copper sheet, contamination causes the water to gather into droplets.

On the bottom half, the water drains away evenly because the surface is clean. This is the water break-free finish you’re aiming for.

Step 1: Make Sure Your Metal Has the Finish You Want

Before cleaning, check that your item has the surface finish you want to achieve.

Electroplating follows the contours of the underlying metal. Therefore, it won’t hide scratches or turn a matt surface into a highly polished one.

If your item needs polishing, complete this first.

If your work needs a lot of polishing and surface finishing you will need to make sure all of the residue from these processes are completely removed before attempting to electroplate.

For more information, see our guide to Hand and Machine Polishing Metal for Electroplating.

Step 2: Removing Polishing Compounds, Grease and Dirt

If you’ve polished your item with Autosol or used a polishing machine, you’ll need to remove any remaining polishing compounds.

Start by cleaning the surface with a suitable solvent or our MetaPrep.

Next, use liquid detergent to remove any remaining solvent or MetaPrep.

Finally, rinse thoroughly under running water until you’ve removed all traces of detergent.

This initial cleaning stage prepares your item for the final cleaning and activation process.

Step 3: Clean and Activate the Surface

Cleaning removes dirt, grease and oil. Activation removes the oxide layer that can form on metal surfaces.

Some metals, particularly stainless steel, nickel and nickel-containing alloys such as nickel silver, need special attention because of their oxide layers.

Spa Plating offers several ways to clean and activate your work. The best method depends on the metal you’re plating, its size and its surface condition.

For Small and Medium-Sized Items

If your item has a fairly smooth surface and isn’t made from stainless steel, nickel or a nickel-containing alloy, we recommend MPU (MetaPrep Ultra).

MPU removes remaining traces of oil while activating the metal surface at the same time.

Apply it using tissue paper, making sure you treat the whole surface.

For Stainless Steel, Nickel and More Difficult Surfaces

If you’re preparing stainless steel, nickel or nickel-containing alloys, we recommend our ActiClean.

ActiClean cleans and activates the surface in one process.

It’s also a useful choice for very large items or those with uneven surfaces.

For this process, use a Carbon Electrode, preferably, or a Platinum Electrode.

For Tank Plating and Items with Recesses

If you’re preparing items for tank plating, you can use our powered Cleaning Beaker together with our Cleaner. You can use our in-house designed and manufactured MultiPlater to power this stage.

This powered immersion method is particularly useful for items with rough surfaces or recesses.

For example, some surfaces may catch on a cleaning swab, while recessed areas can trap traces of MPU. The Cleaning Beaker provides an alternative way to prepare these items.

Step 4: Check for a Water Break-Free Surface

Once you’ve completed the cleaning and activation process, it’s time for the final check.

Hold your item under gently running water and watch how the water behaves.

If it flows evenly across the surface without forming droplets or breaking apart, your item has passed the water break-free test.

However, if the water gathers into droplets or pulls away from certain areas, repeat the appropriate cleaning steps.

Don’t start plating until you’ve achieved a water break-free surface.

Ready to Start Plating?

Once you’ve achieved a water break-free surface, you’re ready to move on to the appropriate plating process for your metal.

Remember, taking a little extra care during surface preparation can make a considerable difference to your final plating result.