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Layout Dye and Scribing Basics
Guide · Updated October 27, 2026
Layout fluid (layout dye) gives you a thin colored coat so scribed lines show bright metal. Good layout is quick, and it catches mistakes before you cut.
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Step by step
- Clean the part: Degrease and deburr it. Dye won't stick to oil.
- Apply a thin coat: Brush or spray one even, thin coat and let it dry.
- Scribe the lines: Use a height gage or surface gage on the plate, or a scriber along a square or rule.
- Punch the intersections: Prick punch lightly, check the location, then center punch.
- Remove the dye: Clean it off with the maker's remover or alcohol.
Tips
- Thick coats chip and give fuzzy lines.
- Use one sharp, carbide-tipped scriber pass.
- Set heights from gage blocks with a surface gage.
Related: height gages, using a surface gage.
Quick shop check
Lay a thin coat of dye and let it dry for about a minute. Scribe with a carbide scriber at a light angle; one firm pass beats several. A good scribed line can be split by eye to about 0.005 in, which is why layout is for rough location and critical features are picked up by indicating.
Worked example: laying out a hole pattern with dye
A plate needs two holes marked from one finished edge. Deburr and degrease the surface, then brush on a thin, even coat of layout dye and let it dry. Set the plate with its reference edge on the surface plate and set the height gage to the first line; scribe one light, steady pass. Reset for the second line and scribe it. Turn the plate to the other reference edge and scribe the crossing lines. Check each line with a scale from the edge, then lightly prick punch where the lines cross and follow with a center punch before drilling.
FAQ
What is layout dye?
A quick-drying colored lacquer, usually blue or red, that shows scribed lines as bright metal.
How do you remove layout dye?
With the maker's remover, or usually denatured alcohol or acetone.
Do I need dye on aluminum?
It helps a lot. Bare aluminum lines are hard to see.
How accurate is scribed layout?
About ±0.005 in to ±0.010 in, which is fine for rough location but not for finish size.
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General shop information only — follow your gage manufacturer's instructions and your quality system.