Craftsman Bio Process cheat sheet

Surface preparation standard: bare substrate must be free of oil, grease, rust, mill scale, and old coating before any bio-based coating is applied.

Substrate moisture content for wood must be measured with a calibrated meter and recorded; typical acceptable range is 12-15% for exterior applications.

Ambient conditions for application: air and substrate temperature 10-30 C, relative humidity below 85%, and substrate at least 3 C above dew point.

Dew point rule: substrate temperature minus dew point must be at least 3 C; otherwise condensation forms and adhesion fails.

Bio-based coatings have shorter shelf life than solvent-borne equivalents; check batch date and store between 5 and 25 C, protected from frost.

Pot life after catalyst or hardener addition is typically 2-4 hours at 20 C; pot life halves for every 10 C rise in temperature.

Mixing ratio must follow the product data sheet by weight, not volume; a 1-2% ratio error can prevent full cure.

Masking and protection: adjacent surfaces must be masked before application; overspray of bio coatings is difficult to remove after cure.

Apply by brush, roller, or spray; spray requires a tip size matched to viscosity, typically 1.8-2.5 mm for high-solids bio coatings.

Wet film thickness (WFT) = dry film thickness (DFT) / volume solids fraction; a 60% solids coating at 100 micron DFT needs about 167 micron WFT.

Recoat window: next coat must be applied within the stated interval (often 8-24 hours); if exceeded, abrade the surface before recoating.

Maintain a wet edge when brushing or rolling to avoid lap marks; work in sections no larger than can be finished before the edge sets.

Do not apply in direct sunlight or when surface temperature exceeds 35 C; flash-off becomes uneven and blistering can occur.

Two thin coats outperform one thick coat; total DFT is the sum of coats, and each coat must fall within the specified range.

Stir bio coatings gently; high-shear mixing entrains air, causing pinholes and foam in the cured film.

Clean tools with the solvent or cleaner named on the data sheet immediately after use; cured bio coating cannot be dissolved.

Dry film thickness is measured with a magnetic or eddy-current gauge; take at least 5 readings per 10 square meters and average them.

Adhesion is tested by cross-cut or pull-off test; cross-cut results are graded 0 (best) to 5 (worst) per the standard classification.

Visual inspection for defects: runs, sags, pinholes, orange peel, and holidays must be recorded with location and size.

Cure check: solvent rub test with a cloth soaked in the specified solvent; no softening or color transfer indicates full cure.

Moisture content of the coated substrate is re-measured after cure; a rise can indicate trapped moisture or insufficient drying.

Acceptance criteria must be defined before work starts; a coat outside the specified DFT range is a nonconformity, not a preference.

Record ambient conditions at start, middle, and end of each application session; these records support any later dispute.

Holiday detection on conductive substrates uses a high-voltage spark tester; voltage is set per the coating thickness.

Certification requires documented evidence: surface preparation records, batch numbers, application logs, and inspection results.

A certificate is issued only when all acceptance criteria in the specification are met and nonconformities are closed.

Inspector qualifications must be current; an expired certificate invalidates the inspection record for certification purposes.

Traceability: each batch of bio coating must be linked to its application location and date in the project record.

Re-testing after repair follows the same assessment protocol; a repaired area is inspected as a new application.

Certification documents must state the standard applied, the test methods used, and the results with units.

Retention period for certification records is set by contract, commonly 5-10 years after project completion.

Any deviation from the specification requires written approval before work proceeds; verbal approval is not sufficient for certification.