Quality control

Registration Marks:

Explanation:

• Registration marks are symbols printed outside the design area of printed materials.
• They ensure that multiple layers of colour or images line up correctly when printed.
• Common in CMYK (4-colour) printing and packaging to maintain accuracy during production.
• Checked by machines or operators during quality control.

Go/No-Go Fixture:

Explanation:

• A go/no-go fixture is a simple gauge used to quickly check dimensional accuracy.
• If a timber component fits the "go" side but not the "no-go" side, it meets tolerance.
• Used in batch production to reduce measuring time and improve consistency.

Using a Depth Stop:

Explanation:

• A depth stop is a device fitted to drills and milling machines to limit how deep a cut or hole goes.
• This ensures consistent depth across multiple parts.
• Important for precision metalworking where exact hole depth is needed.

Laser Cutting Accuracy:

Explanation:

• Laser cutting machines rely on correct settings for material type, thickness, speed, and power.
• Incorrect settings can cause burning, melting, or poor edge quality.
• Calibrating the laser ensures precise dimensions and clean cuts in polymers like acrylic or HDPE.

Repeat Print Accuracy:

Explanation:

• In textile production, repeated patterns must be aligned correctly.
• Accuracy is checked by comparing the print to an original sample or master swatch.
• This ensures consistent colour, spacing, and alignment across the entire fabric roll.

PCB UV, Developing and Etching:

Explanation:

• PCBs are made by exposing a photosensitive layer on a copper board to UV light through a mask.
• The board is then developed, washing away unexposed areas.
• It’s placed in an etching bath to remove excess copper, leaving only the circuit paths.
• Timing and exposure must be precise to maintain circuit accuracy and avoid short circuits or breaks.

Topic test:

Interactive flashcards: