Chemtronics CW2900, CircuitWorks Flex Conductive Pen, 8.5g Pen
Chemtronics CW2900 CircuitWorks Flex Silver Conductive Pen — 8.5g (Discontinued)
The Chemtronics CW2900 CircuitWorks Flex Conductive Pen has been discontinued by the manufacturer and is no longer in active production. MTE Solutions may have limited factory-new surplus stock available — contact us to check current availability before ordering.
The CW2900 was a silver-based conductive ink pen engineered specifically for flexible PCBs and flex circuit applications. Unlike standard silver conductive pens, the CW2900 used a highly flexible polymer binder designed to withstand bending and flexing without cracking or delaminating — making it uniquely suited for membrane switches, flex ribbon cables, Mylar-based circuits, and other flexible substrates.
Replacement Options
| Application | Recommended Replacement | Notes |
|---|---|---|
| Rigid PCB trace repair | CW2200STP (Standard Tip) or CW2200MTP (Micro Tip) | Same silver ink family; 0.02–0.05 ohms/sq/mil; not suitable for flex substrates under heavy bending |
| Flexible PCB / Mylar / ribbon cable | Specialized flexible silver conductive ink | The standard CW2200 may crack on flex substrates — contact MTE Solutions for guidance |
Original CW2900 Specifications (Reference)
| Specification | Value |
|---|---|
| Part Number / SKU | CW2900 |
| Status | Discontinued |
| Ink Type | Flexible silver conductive ink |
| Net Weight | 8.5g (0.3 oz.) |
| Conductivity | 0.05–0.15 ohms/sq/mil |
| Tip Type | Standard tip valve pen |
| Dry Time | Minutes at room temperature |
| Solderable | Yes — at low temperatures |
| Primary Use | Flexible PCBs, membrane switches, Mylar circuits |
| Brand | Chemtronics / CircuitWorks |
Frequently Asked Questions
Is the CW2900 still available?
The CW2900 has been officially discontinued by Chemtronics and is no longer manufactured. Major distributors including DigiKey have classified it as discontinued. MTE Solutions may have limited factory-new surplus stock remaining — contact us at 651.600.3838 or sales@mtesolutionsinc.com to check availability.
What is the best replacement for the CW2900 on a rigid PCB?
For rigid PCB trace repair, the CW2200STP (standard tip) or CW2200MTP (micro tip) are the direct replacements. Both use the same silver conductive ink family with 0.02–0.05 ohms/sq/mil conductivity — better than the CW2900's 0.05–0.15 ohms/sq/mil. These are in active production and stock.
Can I use CW2200STP on a flexible circuit instead of CW2900?
Not recommended for flex circuits that will be bent repeatedly. The CW2200 uses a rigid polymer binder that may crack under mechanical flexing. The CW2900's flexible polymer binder was specifically engineered for flex substrates. For flexible circuit repair, contact MTE Solutions to identify a suitable flexible silver ink alternative.
What made the CW2900 different from standard silver conductive pens?
The CW2900 used a flex-formulated polymer binder that allowed the cured silver trace to bend and flex without cracking or delaminating — critical for membrane switches, flex ribbon cables, and Mylar-based circuits. Standard silver pens like the CW2200 series use a rigid binder optimized for FR4 and ceramic substrates.
