CopperPro Electroforming Solution

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CopperPro Electroforming Solution
Precision Copper Electroforming — Without the Guesswork

Built for electroforming. Trusted for plating.

We have developed CopperPro as a high-performance copper electroforming solution specifically for beaker-based systems. It gives you dense, structurally strong copper builds with exceptional detail reproduction and a brilliant, highly levelled finish.

Why Professionals Choose CopperPro

Clean Process Control
We use insoluble platinised titanium anodes — essential for compact electroforming setups.
No copper sludge. No contamination. Just consistently bright, smooth deposits you can rely on.

Calibrated & Predictable

We have designed CopperPro Electroforming Solution to work directly with our CopperPro Electroforming Calculator.

Simply enter your required thickness, surface area and beaker volume, and you can read off your operating settings immediately reducing the guesswork.

High-Build Performance
You can build fine-grained, durable copper deposits suitable for jewellery, moulds, sculpture, prototyping and technical applications.

More Than Electroforming
When you need decorative copper plating, CopperPro delivers outstanding bright, levelled finishes there too.
For decorative purposes (layers under 10 microns) please use this calculator: CopperPro Calculator

Professional results. Compact setup. Complete control.

CopperPro Electroforming Solution and replenishers are available worldwide.

After striking zinc and zincated aluminium parts with our Alkaline Copper Tank Plating Solution, or  our Alkaline Copper Brush Plating Solution, we recommend a build of to 10 microns with CopperPro Electroforming Solution to protect from corrosion if the part is going to be used outdoors.

Also, as the solution is used,  its acidity increases, you may wish to consider the use of Copper Tank pH Stabiliser to control its acidity especially when plating zinc and zincated aluminium (please refer to Tech Specs for more info).

This zinc shower rail holder has been tank plated with our Alkaline Copper Tank Plating Solution to form an adhesion layer then built up to thickness (10 microns) with CopperPro Plating Solution. Please click on the ‘Process sequences’ tab to see a step-by-step guide to how to use this solution and view the video on the ‘Video’ tab to see the whole process from star to finish.

Copper selectively plated onto jadite using Conductive Ink to render it conductive.

Copper electroformed onto a range of articles.

This video shows you how to copper electroform on resin;

Here’s a list of the kit used in the video;

MultiPlater
Conductive Paint Airbrush Version
Red Combination Lead
Black Combination Lead
Conductivity Tester
Plating Beaker
Beaker Ring
Platinum Rod Electrodes
Anode Bags
Jig Holder
Temperature Probe
Rinse Bottle
Rinse Beaker

Here’s a video showing you how to maintain your electroforming solution with our additives; CopperPro Glossing Agent, CopperPro Brightener and Copper Replenisher

 

Back to Product Description

Product Details

Optimised for Beaker-Based Copper Electroforming

CopperPro is engineered specifically for compact copper electroforming systems where precise control over anode position, agitation and bath stability is essential. Unlike traditional tank formulations, we calibrated this bright acid copper electroforming solution to deliver consistent, predictable performance in laboratory and workshop-scale environments.

You achieve reliable, repeatable results — even in small-volume beaker setups.

Insoluble Platinised Titanium Anode System

CopperPro is designed to operate with insoluble (platinised titanium) anodes because small-scale electroforming demands a cleaner, more controlled approach.

In beaker systems, conventional copper anodes can generate fine copper particles and sludge inside anode bags. Because magnetic stirrers are positioned close to the anodes in compact setups, agitation can draw these particles into the working solution — leading to rough or dull deposits.

By eliminating copper dissolution at the anode, CopperPro helps you:

  • Avoid sludge formation

  • Reduce contamination risk

  • Achieve smoother, brighter deposits

  • Maintain consistent performance in small systems

You stay in control of your surface finish.

Calibrated Process Control with the CopperPro Calculator

We calibrated CopperPro for use with the CopperPro Electroforming Calculator:

https://www.goldn.co.uk/copperpro-electroforming-calculator

This tool removes uncertainty from copper electroforming current calculations.

Simply enter:

  • Required copper thickness

  • Surface area of your workpiece

  • Beaker volume

The calculator provides your operating parameters immediately — no complex equations and no trial-and-error adjustments.

This allows you to:

  • Plan build times accurately

  • Set correct current density with confidence

  • Achieve repeatable thicknesses

  • Improve production scheduling

You focus on creating. The system provides the control.

Advanced Precision Control (Optional)

For customers who require even greater precision, we also manufacture a coulometer system.

A coulometer measures the exact electrical charge (ampere-hours) passed during electroforming, allowing you to correlate copper deposition directly to total charge rather than relying solely on time and current settings.

For most users, the CopperPro Calculator provides more than sufficient control. However, for research, high-accuracy production, additive development or tightly specified technical components, coulometric monitoring offers an additional level of process verification.

Additional precision is available when your application demands it.

High-Build Copper Electroforming Performance

CopperPro supports high-build copper electroforming, allowing you to increase thickness confidently while maintaining:

  • Fine grain structure

  • Strong mechanical integrity

  • Even thickness distribution

  • Bright, highly levelled surfaces

This makes CopperPro suitable for both structural electroforming and demanding decorative copper plating applications.

Whether you are building robust electroforms, reinforcing 3D printed parts, or producing detailed jewellery components, the system maintains clarity and surface quality across the current density range.

Controlled Chemistry

CopperPro is supplied ready to use and non-corrosive on delivery, allowing you to begin work immediately.

As the bath operates, the electrochemical process gradually generates sulphuric acid. Routine monitoring is recommended, along with appropriate end-of-life disposal procedures (see Tech Specs).

Maintain peak performance with controlled additions of:

  • Copper Replenisher

  • CopperPro Brightener

  • CopperPro Glossing Agent

Simple maintenance. Consistent results.

Copper Replenishment in the CopperPro System

CopperPro electroforming systems use insoluble (platinised titanium) anodes. Because the anodes do not dissolve during operation, copper deposited onto the workpiece must be replaced chemically.

The CopperPro system uses two complementary replenishment products to maintain both copper concentration and bath acidity within the optimal operating range.

Copper Replenisher

Copper Replenisher is used to replace the copper plated out during operation and to gradually establish the desired operating acidity of the bath.

CopperPro solution is supplied at a transport-friendly pH of approximately 2. During normal operation, additions of Copper Replenisher replace deposited copper and progressively increase the acidity of the solution until the preferred operating pH is reached.

Copper Tank Replenisher B

Once the desired operating acidity has been established, Copper Tank Replenisher B can be used periodically to replace copper while helping to maintain the bath at a stable acidity.

Used together, these two replenishment products allow operators to establish their preferred operating conditions and then maintain them consistently during extended electroforming runs.

Suitable Applications

CopperPro supports a wide range of copper electroforming and bright acid copper plating applications, including:

  • Jewellery electroforming

  • Sculpture and art casting

  • Mould making

  • Prototyping

  • Technical components

  • 3D printed part metallisation and reinforcement

  • Decorative copper plating

From compact workshop setups to research-level process development, CopperPro provides a controlled, high-performance copper electroforming solution.

Copper Plating on Plastic

Copper plating on plastic is possible with. When used with our CopperPro Calculator, you can now plate on to most non-conductive and metal surfaces to substantial and measurable thicknesses.
You won’t need to do lots of buffing and polishing, as our CopperPro Solution plates consistently bright and smooth.
In this project we have used Conductive Ink (hi-grade) in place of the standard Conductive Paint. The Conductive Ink (hi-grade) is more difficult to apply and cure than Conductive Paint. However it can be transported worldwide and takes a lot less time to build up to brightness than Conductive Paint.

This project has four main stages;

1. Preparing the surface of the plastic model soldier to make it conductive with our Conductive Ink (hi-grade).
2. Preparing your copper plating equipment.
3. Copper plating in the CopperPro Plating Solution.
4. Post plating of silver and gold.

Please note: The Rectifier shown in this project has now been discontinued and replaced by our MultiPlater.

Stage 1. Preparing the surface for copper plating

a) Mounting the model soldier

It’s important to mount you work well before starting as this will make surface preparation and plating much easier. Drill a small guide hole in an area where it can’t be seen. At this point it’s a good idea to calculate the surface area of your item, in preparation for entering the correct settings into the MultiPlater. We estimated that this model has a surface area of approximately 20 squared centimetres.

Screw in a brass screw and then attach a small length of our Gold Plated Jigging Wire to the other end. This will have two functions; it will form a conductive link between the object and the CopperPro Plating Solution and equipment, ensuring a good electrical circuit. It will also be able to be gripped securely in the crocodile clip, making sure there’s no danger of your piece falling in to the CopperPro solution.

We’ll be spraying on our Conductive Ink (hi-grade) to make the surface conductive and prepare it for copper plating. This could also be painted on.

b) Spraying on the lacquer

Adhesion is not so important when plating thick copper layers so either a solvent or water based lacquer should suffice. Where a lacquer is essential and that’s to seal the work piece if it is porous, for example wood.

Wait for 10-15 minutes and once the lacquer is almost dry but retains a little stickiness, either spray or paint on our Conductive Ink (hi-grade).

spraying lacquer

c) Using an airbrush to spray on our Conductive Ink (hi-grade)

Charge your airbrush with our Conductive Ink (hi-grade).

Spray on a fine layer of our Conductive Ink (hi-grade). You only need a small amount of ink. Spray at a distance of 5-6 cm and apply only enough to block out the underlying surface of the object. Leave to air dry for 30 minutes before apply a second coat.

Dry in an oven.

Leave in a fan oven at a temperature of 50 degrees centigrade for three hours.

Please note that this ink dries far quicker and harder at higher temperatures. However most plastics warp at temperatures in excess of 50 centigrade.

The temperature range for drying ranges from minimum of 50 to 80 degrees centigrade.

conductive ink

Stage 2. Preparing your plating equipment

a) Working out the amps for the MultiPlater and plating times

First, work out the surface area of your work in centimetres.

You can then either enter this into the CopperPro Calculator, which you will find on our website and all the calculations will be done for you,

Then you need to decide how thick you require your copper-plated layer to be and therefore how long it should be plated for. If you are plating an item that is quite fragile, you will probably need to build a fairly thick layer of copper 100 microns for example.

calculating electroforming settings

 

b) Setting up your plating beaker

Fill the rinse beakers with tap water and turn the Hot Plate Stirrer on to its lowest setting so that the copper solution is being agitated. Make sure the temperature of the solution is in the range of 18-24 degrees centigrade. Although higher temperatures are possible, brightness falls off rapidly after 25 degrees centigrade. Plug one end of the black lead as shown into the front of the MultiPlater and the other end into the base of the Plating Arm.

copper electroforming kit

c) Setting the volts and amps

Set the amps to that recommended by our CopperPro Calculator. Then turn off the power.

Make sure the black lead is attached to the base on the Plating Stand and the red lead is attached to the Beaker Ring.

 

 

Stage 3. Plating in CopperPro Plating Solution

a) Placing your work into the solution

Lower your work into the solution and start the timer. Turn on Output and check that the amp level is correct; in this case with the plastic soldier it should be reading 0.5 to be increased after after 5 minutes minutes to 0.9 amp.

You should quickly see a layer of copper building on your item.

Please note: When copper plating larger pieces or where the layer of conductive ink is particularly thin, it will be necessary to plate for 5 minutes at a quarter of the recommended amps so as to build up a thick enough layer of copper around the contact area to enable full conduction.

So for example, if the calculator recommends 4 amps, then start at 1 amp for 5 minutes, then turn up to 4 amps after 5 minutes.

b) Finished copper plated soldier

When the time is up, remove your work from the CopperPro solution and pass it through the two rinse beakers. As can be seen in the photograph, your work will be covered in a bright, shiny and substantial layer of copper that will require very little if any, polishing or buffing.

c) Copper plating on other non-conductive surfaces

The same sequence of applying lacquer, conductive ink and then copper plating can be used on natural materials such as shell, wood, stone and leaves.

If you intend to plate on semi-absorbent surfaces such as wood you will need to apply at least 2-3 layers of lacquer to completely seal the surface.

 

For copper plating on shell, the surface of the shell must not come into direct contact with the CopperPro solution as the solution will etch the shell, so every part of the shell must be covered in layers of lacquer.

Electroformed-jewellery

Stage 4. Brush or tank plating subsequent layers

a) Preparing the copper plated surface

Once you have a substantial layer of copper on your piece and you have passed it through the rinse stages, you can now go ahead and plate other layers such as silver or gold. If you wish to gold plate, you’ll need to plate a barrier layer of white bronze or silver beforehand.

For maximum adhesion, we advise that the part is rubbed with MPU and rinsed prior to further electroplating.

b) Brush plating a silver barrier layer

The beauty of Spa Plating’s system is its flexibility. You can move seamlessly between tank, brush and pen plating once you have our Tank Plating Rectifier.

To brush plate a barrier layer of silver, set up your brush plating equipment as normal by attaching an electrode handle fitted with a platinum electrode to the red lead and grip a Conductor Strip into the crocodile clip on the black lead. Estimate how much Silver Brush Plating Solution you’ll need with the online Plating Calculator, then follow the instructions for brush plating silver that you’ll find in previous projects in this manual.

c) Gold brush plating

To gold brush plate the item, calculate how much gold solution you’ll need with our Plating Calculator and then refer to the previous projects that include gold brush plating for guidance.

Only use this calcualtor when plating thick electroforms

How to use this calcualtor

1. In the first box, enter the thickness that you want your item to be plated to in microns.

2. In the second box, enter the surface area of the article in square centimetres (cm2).

3. Enter the volume of your beaker or tank in ml (cm3). Note: This field is optional but useful if you’re tracking the concentration of sulphuric acid generated at the anode.

4. Click the ‘Calculate’ button.

5. Read off the amps that we recommend you plate at for 15 minutes prior to rasing the amps to their full setting.

6. Read off the amp setting for your MultiPlater and the plating time.

7. If using our Coulometer, note the number of coulombs you should plate to. Using our coulometer is far more accurate than standard amp-hour meters especially when plating small items.

8. If using an amp-hour meter, take a note of the amp-hours you should plate to.

9. Then read off the volume or weight of CopperPro Brightener to add. Please note that for small items where you’re adding a fraction of a millilitre of CopperPro Brightener, we strongly advise that you weigh out your addition on scales accurate to at least 2 decimal places, preferably 3 decimal places. You can purchase our 1ml syringes fitted with flexible safety needles that are ideal for dispensing the brighteners.

10. Similar to point 8 above, read off the volume or weight of CopperPro Glossing Agent to add.

11. Next is the weight of copper replenisher to replace the copper plated on the work piece.

12. Sulphuric is generated at the platinum/inert anode during the process. You can read off the weight of sulphuric acid produced in this box.

13. The increase in concentration of sulphuric acid can be read off in this box. Please note that it’s only displayed if you inputed the volume of your beaker or tank in the input fields. If you didn’t include it, only N/A wish be shown meaning ‘not applicable’.

Operating Conditions and Deposit Data

 

Plating Factor 0.03 A/cm2
Plating rate 0.67 micron per minute at 0.05A/cm2
Temperature 18 – 30°C (optimum 25°C)
pH (of working solution) 0 – 2
Agitation Medium (See notes)
Additive system 2-brightener dye-based system: CopperPro Brightener and CopperPro Glossing Agent
Addition rate for CopperPro Brightener 0.08 millilitre or gram per 1000 coulombs (0.28 Ah)
Addition rate for CopperPro Glossing Agent 0.08 millilitre or gram per 1000 coulombs (0.28 Ah)
Addition rate for Copper Replenisher 1.3 grams per 1000 coulombs (0.28 Ah)
Rate of generation of sulphuric acid 0.51 grams per 1000 coulombs (0.28 Ah)
Electrode Platinum electrodes (bagged)
Cathode efficiency Above 99% at Plating Factor = 0.035A/cm2
Hardness of deposit 160 VPN falling to 100 VPN over 5 days at room temp
Density of deposit 8.9 g/cm3
Stress Low (Tensile)
Special storage requirements None
Shelf life Over 2 years
Health and Safety classification Harmful
Transport (UN number) CopperPro Plating Solution is not classified as dangerous for transport.

 

Notes:

 

  • If particulate contamination enters the solution, filter using our filter kit.
  • We recommend that the solution is filtered after major additions of Copper Replenisher.
    Using our Filter Pump greatly facilitates this process.
  • Brightener additions should be made at the start of plating if possible. Additions can
    be determined using the CopperPro Calculator by clicking Here.
  • Higher temperatures favour less burning on exposed areas ie: sharp edges or pointed parts.
  • A higher agitation rate allows for a higher Plating Factor to be used leading to a
    higher plating rate.
  • Build up of blue crystals is usual on the electrode ring. Remove by scraping them
    back into the solution and allow to dissolve before commencing plating.

General guide;

Certain small items, for example Swabs, Nibs and Plating Pens can be sent by normal post within the UK

  • The courier option for UK deliveries is FedeX and APC. Delivery times range usually from 2 – 5 working days.
  • Royal Mail option is available on a limited range of non-liquid orders. Delivery from 5 – 10 working days.
  • Free UK mainland delivery available on orders over £200
  • International orders usually 5 – 10 working days.

For all price quotations for deliveries, please add your items to our shopping cart. You will be able to see the shipping costs by clicking on the ‘Calculate shipping’ button in the cart and before checking out.

Please click on the link below to download the SDS for this product:

CopperPro Electroforming Solution safety data sheet.

Copper Plating & Electroforming Troubleshooting Guide

This guide helps you diagnose and correct common copper plating problems and copper electroforming defects when using the CopperPro system.

Most faults fall into four areas:

  • Electrical setup

  • Chemical balance

  • Contamination

  • Agitation or temperature control

Because CopperPro is a calibrated electroforming system, issues are usually traceable and correctable with small adjustments.

Copper Plating Problems (Conductive Materials)

No Copper Plating at All

One of the most common copper plating problems is complete failure to deposit copper.

Possible Causes

  • No current (MultiPlater in standby)

  • Poor electrical connection

  • Reverse polarity

  • Solution contamination

  • Damaged platinum electrode (rare)

How to Fix

  • Confirm the green indicator is active (not Standby).

  • If a red light appears, inspect the circuit for breaks.

  • Check all electrical connections.

  • Confirm polarity: black lead to workpiece, red lead to beaker ring.

  • Replace solution if contamination is suspected.

  • Inspect platinum rods for mechanical abrasion.

Dull Copper Plating (Especially in Recesses)

Dull copper plating usually indicates incorrect current density or additive imbalance.

Possible Causes

  • Current too low

  • Brightener/Glossing Agent imbalance

  • Temperature outside operating range

  • Low conductivity (new bath)

  • Excess copper concentration

Corrective Action

  • Recalculate current using the CopperPro Calculator.

  • Add 0.5 ml Brightener per litre. If needed, repeat and add 0.5 ml Glossing Agent.

  • If imbalance persists, plate on scrap at 1 amp/litre for 2 hours (no Replenisher), then rebalance additives.

  • Maintain temperature within specification (see Tech Specs).

  • Plate out to increase conductivity naturally.

  • If copper content is high, continue plating without adding Replenisher.

Best Practice:
Split larger additive corrections into 30-minute intervals to maintain bath stability.

Burnt or Nodular Copper Deposits (Edges & Corners)

Burnt copper plating typically results from excessive current density.

Possible Causes

  • Current too high

  • Brightener deficiency

  • Workpiece too close to anode

  • Low copper content

  • Poor agitation

Corrective Action

  • Reduce current (confirm using the CopperPro Calculator).

  • Add 1 ml Brightener + 0.2 ml Glossing Agent per litre.

  • Increase anode spacing.

  • Add Replenisher (40 g/litre) if solution appears pale.

  • Improve agitation.

  • Keep temperature below 25 °C to maintain brightness.

For highly controlled production, advanced users may monitor ampere-hours with a coulometer to verify deposition accuracy.

Copper Plating Roughness or Matt Finish

Likely Cause

  • Particulate contamination

Solution

  • Filter solution into a clean container.

If deposits are bright but rough, ensure Replenisher is fully dissolved. If it no longer dissolves, the bath may have reached end of life and should be replaced.

Copper Plating Pitting

Pitting in copper plating appears as small holes in the deposit.

Possible Causes

  • Air bubbles

  • Particulates

  • Oil or grease contamination

Corrective Action

  • Fit anode bags.

  • Filter solution.

  • Treat with Carbon Powder.

Copper Plating Adhesion Problems (Peeling)

Poor adhesion is typically related to cleaning or substrate compatibility.

Possible Causes

  • Inadequate cleaning

  • Incompatible base metal

Corrective Action

  • Review metal-specific cleaning stages (see Online Manual).

  • Consider a gold flash intermediate layer (brass, steel, stainless steel).

Skip Plating or Unplated Areas

Likely Cause

  • Incomplete cleaning or air entrapment

Solution

  • Check for water breaks.

  • Reduce stirring vortex.

  • Ensure filtration system does not draw in air.

Copper Electroforming Defects (Non-Conductive Materials)

Electroforming defects usually relate to the conductive coating rather than the copper plating solution itself.

No Electroforming Deposition

Possible Causes

  • Conductive silver layer fused at contact point

  • Conductive coating not fully dry

Corrective Action

  • Reapply coating, especially at wire contact point.

  • Start at half current for 5 minutes, then increase to calculated setting.

  • Allow full drying (overnight recommended).

Patchy Electroforming or Poor Coverage

Possible Causes

  • Conductive layer too thin

  • Inadequate drying

  • Ink not properly mixed

Corrective Action

  • Reapply conductive coating.

  • Allow full drying time.

  • Shake conductive ink thoroughly before use.

Electroforming Peeling (Including Silver Layer)

Possible Causes

  • Substrate incompatible with binder

  • Insufficient surface key

Corrective Action

  • Apply compatible intermediate layer.

  • Lightly abrade surface before coating.

Electroforming Coverage Problems in Recesses

Possible Causes

  • Hydrophobic surface

  • Poor spray penetration

  • Air entrapment

Corrective Action

  • Increase agitation.

  • Tap workpiece gently to release bubbles.

  • Direct solution into recesses using a pipette.

Plating on surfaces metalised by painting/spraying Conductive Silver Paint or Conductive Ink (hi-grade)

  • Usually there’s no need to clean the article. Immerse it directly in CopperPro and plate according to the parameters outlined by the CopperPro Calculator.
  • It’s good practice—especially when metallizing a surface with high-grade conductive ink—to start with lower amperage for the first five minutes. This helps prevent the conductive silver film from fusing at the interface between the film and the wire or gig holding the piece. This is discussed in greater detail under the FAQs tab.
  • See notes below and FAQs.

Plating on zinc (also see notes below)

  • Degrease
  • Electroclean
  • Rinse
  • Microetch in Activator for 20 – 30 seconds
  • Rinse
  • Plate for 5 minutes at plating factor 0.01 A/cm2

You can now leave the surface with its matt/satin finish or hand polish using Autosol.
You can also apply either tank or brush plated layers.
If the item is likely to be used outdoors, then we advise a copper layer of 5 – 10 microns
which can be plated quickly using CopperPro Plating Solution.
If nickel tank plating, polishing may not be necessary as the nickel brightens as it plates.

Plating on to Aluminium

  • Degrease
  • Electroclean
  • Rinse
  • Zincate in Zincate Dip for 30 seconds to 2 minutes
  • Rinse
  • Plate for 5 minutes at plating factor 0.01 A/cmhttps://www.goldn.co.uk/product/zincate-dip-uk-and-eu

The same post plating options apply as for zinc above.

Plating on to steel

  • Degrease and remove any traces of rust
  • Electroclean
  • Rinse
  • Dip in Activator or ActiClean for 30 seconds – 1 minute
  • Rinse
  • Plate for 3 – 5 minutes at plating factor 0.01 A/cm
  • Rinse and plate in CopperPro Plating Solution to the thickness you require

Plating on to brass, bronze, pewter and other tin based alloys

  • Degrease
  • Electroclean
  • Rinse
  • Dip in Activator or ActiClean for 30 seconds – 1 minute
  • Rinse and plate in CopperPro Plating Solution to the thickness you require

Notes
1) Please note that the Activator dip should be kept exclusive to a single metal for example, if the Activator
has been used for zinc, it is not advisable to use the same solution for steel.
2) Most zinc is cast and contains surface impurities that need to be mechanically removed to achieve good adhesion.
This can be done in a variety of ways including abrading, polishing or tumbling in a barrel with abrasive medium added.
Poorly prepared zinc usually results in deposits which bubble up.
3) For maximum adhesion, we advise a quick power clean (30 seconds) followed by a dip in Activator or Acticlean after plating with CopperPro Plating Solution and before continuing to any further plating process.
4) When plating on to a silver metalised surface, especially a sprayed silver surface where the layer if quite thin, it’s best practice when starting plating to start at a lower current (amps) for a few minutes to minimise the chance of the conductive surface fusing between the plating jig (usually jigging wire) and the silver surface.

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