Measuring and Layout — FAQ
What size feeler gauge do I need for spark plugs?
Most automotive spark plugs require 0.020-0.040 inch (0.5-1.0mm) gaps. A set covering 0.001-0.04 inch handles all standard and performance applications. Always check your vehicle's specifications—some imports use metric measurements, making dual-marked sets essential.
Straight or angled blades for engine work?
Use straight blades for accessible spark plugs and standard gaps. Angled blades are crucial for overhead cam valve adjustments where straight blades can't reach. For comprehensive garage work, choose a 2-piece set with both configurations or a single set with offset blades.
How many blades should a garage set have?
Minimum 25 blades covers basic maintenance. 32-blade sets offer better versatility for engine building. Sets with 48 blades (32 straight + 16 angled) provide maximum coverage for professional-level work without buying multiple tools. More blades mean fewer gaps in measurement range.
Stainless steel vs carbon steel feeler gauges?
Stainless steel resists garage humidity and oil exposure without maintenance—ideal for tools stored long-term. Carbon steel costs less but requires oil coating to prevent rust. For garage environments where tools sit for months between uses, stainless steel maintains accuracy longer.
Can I use automotive feeler gauges for guitar setup?
Yes, but choose sets with offset or tapered blades to avoid scratching frets. The same precision works for string height and neck relief measurements. Stainless steel prevents rust from finger oils. Many guitar techs prefer automotive-grade tools for their durability and accuracy.
How do I clean and maintain my feeler gauge set?
Wipe blades with shop towel after each use to remove oil and debris. For stainless steel, occasional brake cleaner spray prevents buildup. Store in protective holder to avoid bending. Never force blades into tight gaps—this creates inaccurate measurements and damages edges.
