VECTOR COLOR MATCHING INSTRUCTIONS

Vector Matching Index

1.  Colors to Match     White & Grays

2  What is Cure Offset?

3. Understanding the C- Lab Color System

4. Saving Matching Information

5. How the Vector Color Matching System Works

6. Common Mistakes in Color Matching

7. How to Match Gelcoat Using the Vector System

8. How to use White Brushing Gelcoat Tint feature

1. Color To Match

The Vector Color Matching System will match White & Grey Gelcoats.   We hope to have reds, greens blues and Yellows sometime in the future.

Gray Color Matching Procedure

     1.  Begin with Rayplex White Gelcoat as the base material (application by brush or spray).
     2.  Incrementally add Rayplex Black Gelcoat while mixing thoroughly to reduce the L value to the              target specification.
      3.  Once the desired lightness (L value) is achieved, fine-tune the gray by adding small amounts of             yellow or blue LDX Gelcoat to correct hue bias as required.

2. What Is Cure Offset

• Vector Color Match – Cure Offset Instructions

  Gelcoat typically dries slightly lighter on the L* scale, usually in the range of 1.4 to 1.8 units.

  Understanding this shift helps achieve near-perfect color matches. Keep in mind that the cure offset may vary from batch to batch of gelcoat.

  Purpose

  To achieve the most accurate colour match possible, each new batch of white gelcoat must be checked for cure offset—the L # colour shift that occurs as gelcoat transitions from wet to fully cured.

  1. What Is Cure Offset?

  Cure offset is the measurable change in colour values (L\#, a\#, b\#) that happens during the curing process. Most commonly, the L\# value increases, meaning the cured gelcoat appears slightly lighter/whiter than the wet sample.

  2. How to Measure Cure Offset

  Step 1 — Measure Wet Gelcoat

  Use your NIX Meter  to record the wet L\#, a\#, and b\# values.

  Step 2 — Allow Gelcoat to Fully Cure

  Ensure the sample is completely cured before taking the second reading.

  Step 3 — Measure Cured Gelcoat

  Record the cured L\#, a\#, and b\# values.

  Step 4 — Calculate Cure Offset

  Subtract the wet readings from the cured readings:

  3. Example

  Stage	L\#	a\#	b\#
  Wet Gelcoat	94.38	0.66	0.03
  Cured Gelcoat	95.98	0.72	0.23
  Cure Offset	1.50	0.06	0.20

  These cure‑offset values are added to the matched wet readings in the Vector Color Match system to predict the final cured colour.

  4. Important Notes
  • Every new batch of white gelcoat can behave differently.
  • For the most accurate match, record cure‑offset values for each batch.
  • Apply the batch‑specific offset numbers when performing colour matches.
  • Keeping a log of all batch offsets ensures consistent, repeatable results.

• How It Is Computed

  1. Measure the CIELAB (C*Lab) values of the gelcoat while it is still wet.
  2. Mix a small amount of gelcoat with catalyst and pour it into a small lid or sample container.
  3. After the sample has fully cured, measure the CIELAB values again.
  4. Subtract the cured values from the wet values. The difference is the cure offset.
  5. Enter the Cure Offset numbers in #4 of the Vector Match Program.
   
  Example of Cure Offset sample numbers for Rayplex white gelcoat.   
  L 1.76  A .02  B -.19

3. Clab Color Space
Understanding C-Lab Color Space 3  VIDEO

🧪 Overview

This guide provides step-by-step instructions for accurately matching gel coat color using the C LAB color system. The process involves two key stages:  First take a reading for the sample to be matched using the Nix color meter.

1. Whiteness (L number) Adjustment
2. Hue and Shade Matching

1️⃣ Step One: Adjusting Whiteness (L Number)

• Start with a Base Gel Coat: Use a white base gel coat as the starting point.
• Understand the L Number: The L number represents the level of whiteness. White gel coats typically range from 94 to 96.
• Matching the Sample’s L Number:
• If the gelcoat to be matched called the sample.  If the  L number is around 96, use RAYPLEX # 317 Super White Gel Coat as your base.
• To lower the L number, incrementally add black pigment until the whiteness level closely matches.
• Tip: Always mix thoroughly and test small batches to monitor changes.

2️⃣ Step Two: Hue and Shade Matching

• Select Your Color Pigments: Use red, green, yellow, blue, or other pigments to adjust tint and saturation.
• Make Gradual Adjustments: Add pigments in small amounts and blend thoroughly. Compare your mixture against the sample under consistent lighting conditions.
• Visual Harmony: Ensure the final gel coat matches the sample not only in brightness but also in hue and shade overall.

4. Saving Matching Information
    In the upper Left Top corner is a Blue Box with lines in it which is a file Menu.
      Use this to save and retrieve  the information about the match.  Similar to File 
      menu in Word or Excel Programs.

5. How the Vector Color Matching System Works

1. Take a Color Reading Begin by taking a reading from the gelcoat you want to match. Enter these numbers into the Rayplex Reference Program. A dot will appear near the closest LDX Gel number, indicating the starting color. Sometimes, two colors may be close—choose the closest one.

2. Pigments Used in Matching The Vector Color Matching program is specifically designed for white or off-white gelcoat. Through experience, we’ve found that most white gelcoats are best matched using one or a combination of the following pigments: Chrome Yellow, Iron Oxide, Oxide Tan, Deep Green, and Black (which adjusts luminosity or L#).

3. Why "Vector"? The name "Vector" was chosen because pigments are added in a straight-line directional manner, resembling a vector path.

4. Color Shift in Curing Process Taking a C-LAB color reading from both liquid and cured gelcoat from the same batch will reveal a slight color shift.

5. Using a Nix Meter with Film Readings are taken using a Nix Meter, either with a piece of film over the gelcoat or directly without film. The film introduces a slight color shift due to its subtle color cast: L3.2, A -0.04, B 0.82, referred to as a film offset.

6. Recording Readings

   • Take a color reading from the gelcoat using the Nix Meter (refer to Video #6).

   • Enter the C-LAB color numbers into Reference #2 and #3.

7. Adjustments for Cured Gelcoat As gelcoat cures, its color shifts slightly lighter.

   • Take readings from the matched gelcoat and the cured sample using film.

   • Enter these numbers in Cure Offset in Reference #4.

      

6. Common Mistakes in Gel Coat Color Matching

1. Skipping L Number Calibration First

• Jumping into tinting before matching the whiteness (L number) can throw off your final shade.
• Always start by adjusting the L value using white and black pigment before worrying about hue.

2. Inconsistent Lighting Conditions

• Evaluating color under different light sources (sunlight vs. fluorescent) can cause inaccurate matches.
• Always use consistent lighting—preferably daylight-balanced—to assess color accuracy.

     3.  Light Leakage

          Stray light can effect the readings.  One low cost solution is to take a small cardboard box and spray

          the inside with flat black paint.  Place the sample inside the box and take the C Lab reading.

Color Matching Update
We're also making a new video to explain the color matching process more clearly. It breaks the process into two simple steps:

1. First, match the L component in the LAB color space. This usually controls the lightness or brightness (often seen as white).

2. Next, match the A and B components, which control the hue and color shading.

3. Were adding better explanation of the cured gelcoat Offsets.  

7. How to Match Gelcoat Using the Vector System

1. • Wet Film Number is the combination of the  Cure numbers applied to 
     the gelcoat.  This takes into account the color shift of the film and the color shift of the gelcoat as it cures.  

   • Area #5 Cured Gelcoat  Number

     Adjustments for Cured Gelcoat As gelcoat cures, its color shifts slightly lighter.

     • Take readings from the matched gelcoat and the cured sample using film.
     • Enter these numbers in Cure Offset in Reference #4.
     • This number will vary depending on the type of gelcoat used and the manufacturer.

8. How to use White Brushing Gelcoat Tint feature

USE AT OWN RISK! This is an incomplete feature and results will vary!

The White Brushing Gelcoat tinting feature gives you guidance into one of the first steps of matching gelcoat, which is tinting the L# of your mix.

After you have inputted the Matched Colour, Mix 1 (your starting mix), and your cure offset LAB values, there will be a "Tint" button on the right side of Mix 1, clicking it will open the Tint feature.

Your information is automatically inputted, and a calculation is made to determine how much black gelcoat would need to be added.
If not filled in already, or if the entered value is incorrect, you can enter the amount of grams your current mix is, so the program can tell you how many grams of black gelcoat to add.

Once all your information is inputted, at the bottom of the modal is table that shows you how many grams to add with different offsets.
Which offset you use will be up to you, however it is useful to know a general term:
- Use a higher L# Offset if you will need to add more colour to your gelcoat, as these colours will also bring down the L# of your mixes.
- Use a lower L# Offset if you don't need to add much or very little colour to your gelcoat.

The table will show you a "grams to add" of black, calculated based on what your "grams of mix" value is.
If the "grams of mix" value is incorrect to what you add your black into, your results will be drastically different.