The five-step workflow
Preserve
Remove loose debris gently. Do not trim, stretch, swell, or reshape the original.
Capture
Use a flatbed scan when possible. Otherwise photograph straight overhead in even light.
Measure
Verify the outside size, important holes, and any passage whose location matters.
Identify
Add manufacturer, model, year, engine or system, and the component being sealed.
Proof
Compare the scaled proof against the part before approving the cut.
Best capture methods
Flatbed scan
Usually the best starting point for a gasket that fits on the glass. Scan at 300 dpi or higher, turn off automatic cropping, include the entire gasket and a ruler, and save as PNG or PDF.
Overhead photo
Use when the gasket will not fit a scanner. Place it on a flat contrasting background with a ruler in the same plane. Keep the camera centered and parallel to the gasket.
Measurements worth recording
- Overall width and height, or outside diameter.
- Inside opening dimensions or bore diameter.
- Hole diameters and center-to-center spacing.
- Bolt-circle diameter when holes are evenly spaced.
- Corner radius or unusual edge features.
- Thickness of the removed gasket, noting that a used gasket may be compressed.
- One known dimension visible in the scan or photo.
When the old gasket is torn
Do not invent the missing edge. Arrange all surviving pieces without overlap, photograph the mating surface if accessible, and mark which areas are damaged. Symmetry may help reconstruct a missing section, but that is an inference that must be checked against the equipment.
Before approving the proof
- Confirm the stated overall dimensions.
- Count every hole and passage.
- Check orientation: front/back and top/bottom.
- Compare hole centers to the mating surface.
- Confirm material and thickness separately from geometry.
Print the free tracing kit
Use the calibration rulers and project checklist to make the image easier to scale.