PCB Fabrication ChecklistSetting Up A PCB ShopPCB Substrates
Selection and Preparation
FormattingCleaningDrilling Copperclad SubstratesThrough Holes and ViasHolewall ActivationElectroplating 
Hull Cell AnalysisAcid Copper Plating BathsAcid Copper Plating TankBubble Assisted ProcessDrillingAssemblingLocatingAcid Copper Plating SolutionCrystalline copperCarbon Treating AcidElectroplatingAcid CopperTin/Lead (Solder)Tin/Lead Plating TankTin/Lead Plating SolutionAcid Tin (Bright Tin)Photoresist and SoldermaskLaminationRoll LaminationApplying Laminating FilmsPouch LaminationDry-film LaminationPeeling BackLaminating Dry-FilmsImagingDevelopingRolling Your Own Develop.Etching TechniquesChemical AnalysisCopper ConcentrationSulfuric AcidChloride IonSolderOn acid concentrationTin concentrationLead concentrationAdditive and carrier levelsHydrogen PeroxideOrganic Stabilizer
Before handling and/or using any toxic and/or highly corrosive material, you must familiarize yourself with its safe handling procedures and analysis techniques.
If your copper plating tank has a volume of less than 10 gal (40 liters), you might find it beneficial to mix your electrolyte from premixed components. These are mixed in a fixed ratio with battery acid to make a ready-to-use plating bath. The electrolyte is maintained using organic additives, hydrochloric acid, and battery acid as indicated by analysis.
| Using Premixed Makeup Solutions | ||
| Component | Quantity | |
| CG CLX Makeup solution* | 2 parts | |
| 35% sulfuric acid (car battery acid) | 1 part | |
This bath is rated for continuous plating at 10 to 30 Amps per Square Foot (ASF) with a recommended agitation of 2 Cubic Feet per Minute (CFM) of clean dry air per square foot of bath bath surface area. |
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If the volume of your tank equals or exceeds 10 gallons, you will probably be better off buying the makeup components in bulk and mixing your bath from scratch. This is especially true if you are setting up a PCB prototyping shop where the cost per board needs to be well controlled.
| Bulk Acid Copper Electrolyte Recipe | ||
| Component | To make 100 liters, add: |
To make 10 gallons (US), add: |
| deionized (or distilled) water | 41 liters | 4.10 gal |
| Concentrated copper sulfate (35 oz.CuSO4/gal)* | 30.5 liters | 3.05 gal |
| 35% sulfuric acid (car battery acid) | 29 liters | 2.86 gal |
| Concentrated hydrochloric acid (35% HCl) | 13.3 ml (cc)** | 5 ml (cc) |
| Copper Gleam CLX Start-Up | 1.25 liters | 0.125 gal |
| This bath is rated for continuous plating at 10 to 30 Amps per Square Foot (ASF) with a recommended agitation of 2 Cubic Feet per Minute (CFM) of clean dry air per square foot of bath bath surface area. | ||
*Copper sulfate can also be added as crystalline copper sulfate pentahydrate. For the proper concentration, add 0.625 lb (284 g) of crystal to each gallon of solution. To insure complete dissolution, the bath should be pre-heated to 120°F (49°C) and stirred vigorously while the crystals are added. Generally speaking, it is better to add the copper sulfate crystals to the solution before adding the acid. It will dissolve easier and mixing will pose less of a hazard. |
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| Component | To make 100 liters, add: |
To make 10 gallons (US), add: |
| deionized (or distilled) water | 70.9 liters | 7.09 gal |
| Copper Sulfate Pentahydrate Crystals (CuSO4.5H2O) | 7.5 Kg | 6.25 (2.84 Kg) |
| 35% sulfuric acid (car battery acid) | 28.6 liters | 2.86 gal |
| Concentrated hydrochloric acid (35% HCl) | 13.3 ml (cc)** | 5 ml (cc) |
| Copper Gleam CLX Start-Up | 1.25 liters | 0.125 gal |
**Adding 10 mL of 35% HCl to 100 gallons of electrolyte adds 12 ppm of chloride ion to the solution. For the recommended level of 60 ppm, add 0.5 mL (cc) of HCl to every gallon of plating solution. Do Not Add Too Much! |
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included by permission of Think & Tinker, Ltd copyright 1986 to 2010