Readiness report
Micro Pressure Sensor Model and the Wheatstone Bridge (SCME) · 2026-07-19 14:18 · complete · 16 searches, 0 pages fetched
Readiness: Micro Pressure Sensor Model and the Wheatstone Bridge (SCME)
Verdict: Ready · 2026-07-19 · est. parts cost $50–$120
This is a cold check for the Micro Pressure Sensor Model lab; no previous readiness report exists. All required materials are currently available from major retail and electronics distributors. The primary cost driver is the specialty 3M conductive tape, though acceptable lower-cost substitutes have been identified. The lab remains implementable as long as the SCME Instructor Guide stencil is available to the instructor.
Action required
None — all checked parts are sourceable.
Parts
Sensed Materials and Active Components
| Part | Spec/Package | Status | Stock | Price | Source |
|---|---|---|---|---|---|
| Pencil Lead (Graphite) | 0.9 mm HB | Active | High | $5.99 | Walmart |
| Rubber Cement | Solvent-based | Active | High | $2.84 | Walmart |
| Copper Foil Tape | 3M 1181, 1/4 inch | Active | 1,016 | $33.32 | DigiKey |
| Batteries | 1.5 V AAA | Active | High | $7.99 | Harbor Freight |
| Battery Holder | 2xAAA with leads | Active | High | $1.85 | DigiKey |
Structural Components and Housing
| Part | Spec/Package | Status | Stock | Price | Source |
|---|---|---|---|---|---|
| Paint Cans | 1-quart metal | Active | High | $1.25 | Best Containers |
| Balloons | 12-inch latex | Active | High | $1.00 | Walmart |
| Plastic Syringes | 3 cc (3 mL) | Active | High | $0.26 | VitalityMedical |
Tools and Instrumentation
| Part | Spec/Package | Status | Stock | Price | Source |
|---|---|---|---|---|---|
| Multimeter | DMM (mV/Ω range) | Active | High | $19.96 | Walmart |
| Alligator Clip Leads | Standard pair | Active | High | $3.49 | Harbor Freight |
| Mortar and Pestle | Lab/Kitchen grade | Active | High | $4.50 | Home Science Tools |
| Calibration Weights | 50 gram | Active | High | $6.86 | Walmart |
Consumables and Shop Supplies
| Part | Spec/Package | Status | Stock | Price | Source |
|---|---|---|---|---|---|
| Painter's Tape | 1 inch wide | Active | High | $1.75 | DPCIwholesale |
| Cardstock | For stencils | not checked | — | — | — |
| Paperclips | Large | not checked | — | — | — |
| Ice Pick or Nail | For punching metal | not checked | — | — | — |
| Protective Gear | Gloves/Glasses | not checked | — | — | — |
Substitutes
| For part | Substitute | Differences | Judgment |
|---|---|---|---|
| 3M 1181 Tape | Micro Center Copper Tape | Generic; significantly lower cost ($7.99 vs $33.32). | Acceptable; dual-conductive requirement met. |
| 3M 1181 Tape | Lowe’s Double-Sided Tape | Generic; retail available ($10.99). | Acceptable; dual-conductive requirement met. |
| Calibration Weights | Large steel washers | Commodity hardware; weight is approximate. | Acceptable per snapshot guidelines. |
Verify any substitute against its datasheet before ordering.
Other dependencies
- SCME Instructor Guide (p. 27): Necessary for the bridge pattern stencil sized for 1-quart cans; not checked (assumed provided with lab).
- Graphite/Rubber Cement Mixture: Success depends on viscosity (aim for "toothpaste" consistency). Procedural dependency.
- Airtight Seal: Procedural requirement for the syringe-to-can interface; may require additional sealant if "snug fit" fails.
Watch list
- Balloon Fatigue: Latex loses elasticity over repeated pressure tests; ensure ample stock of 12-inch balloons is available for replacement.
- Copper Tape Pricing: 3M 1181 is a high-cost item; instructors should monitor the availability of generic dual-conductive substitutes to manage budget.
- Syringe-to-Can Interface: Monitor for air leaks at the reference port, as this will prevent successful calibration.