How to Apply Awlgrip High Build
Epoxy Primer
A plain-English walkthrough for spraying High Build Epoxy Primer (D8002 or D9002 + D3002) — even if this is your first time working with a two-part epoxy primer.
What Is High Build Primer, and Why Would You Use It?
If you've never sprayed an epoxy primer before, start here — this section explains what the product actually does in plain terms.
Think of High Build as "fill primer." It's thick, it sprays on heavy, and its whole job is to fill in small imperfections, sanding scratches, and surface texture so that what's underneath your final paint job is smooth and flat. It's not a finish coat — nobody ever sees it once you're done. It's the layer that makes the finish coat look good.
It's a two-part epoxy, meaning you mix a base paint with a separate converter (sometimes called a hardener) right before spraying. Once mixed, it starts curing — so you're working against a clock, but not an unreasonably tight one (you'll have about 8 hours).
Is High Build the Right Product for This Job?
Quick gut-check before you buy. If any of the "no" items apply, this isn't the product you want — give us a call instead.
What You'll Need Before You Start
Gather everything first. Nothing kills a two-part epoxy job faster than realizing mid-mix that you're missing a reducer.
Materials
Equipment
Where High Build Fits In the Bigger Picture
High Build is one step in a sequence. Here's the order things happen, so you know what comes before and after — and you don't skip a step by accident.
| Position in System | Product | Purpose |
|---|---|---|
| Seal Coat (optional) | 545 Epoxy Primer | Seals bare wood or fiberglass before High Build |
| Fairing (if needed) | Awlfair LW / Sprayable Fairing Compound | Fill, fair, and block sand to shape |
| Surfacing / Build | High Build Epoxy Primer ← You are here | Fill texture, build film, create smooth base for finish priming |
| Finish Prime | 545 Epoxy Primer | Final prime coat before topcoat — sand to 220 grit |
| Topcoat | Awlgrip Topcoat / Awlcraft 2000 / Awlcraft 3000 | Color and gloss finish coat |
Step 1: Prep the Surface
This is the step people are most tempted to rush. Don't. Primer only sticks as well as the surface underneath lets it.
Degrease the Surface
Wipe the entire surface with Awlprep T0008 (North America) using the two-cloth method: apply solvent with one clean cloth, then immediately wipe it dry with a second clean cloth before it evaporates on its own.
Sand the Substrate
Sanding gives the primer "tooth" — microscopic scratches for it to grip onto. Smooth, glossy surfaces don't hold paint well. What grit you use depends on what you're sanding:
- Gelcoat / Fiberglass: 100–150 grit paper. Remove all gloss and shine — you should not see any shiny spots left when you're done.
- Wood: Smooth sand with 80–100 grit paper.
- Previously faired surface: Block and machine sand 36–80 grit, then finish with 80–120 grit before priming.
- Previously painted (rough condition): Sand with 120–180 grit to remove gloss.
Apply 545 Epoxy Primer First — If You're Starting From Bare Substrate
If you're spraying High Build directly onto bare gelcoat, fiberglass, or wood, seal it first with one or two coats of 545 Epoxy Primer. Let that cure a minimum of 12 hours before High Build goes over it. (If you're spraying over a properly cured fairing compound instead, you can skip this step and go straight to High Build.)
Final Dust Removal
Blow off all sanding dust with clean, dry compressed air. Dry-wipe with clean rags to pick up residue, then do one more wipe with Awlprep T0008. This is your last chance to catch dust before it gets trapped under your primer.
✓ You're ready to move on when...
- The surface has no remaining gloss or shiny spots anywhere
- You can't see or feel any dust on the surface
- If you sealed with 545 first, it's had at least 12 hours to cure
- The work area is clean enough that a breeze won't kick dust back onto your wet primer
Step 2: Mix and Wait (Don't Skip the Wait)
The ratio is simple — equal parts by volume. The part people get wrong is rushing past the 15-minute wait.
D8002 or D9002
D3002
T0006 or T0176
Here's the order, step by step:
Measure Equal Parts Base and Converter
Use a mixing container with volume markings. The ratio is 1:1 by volume — so equal amounts of base and converter, not by weight. A simple example from the TDS: 8 oz. base to 8 oz. converter.
Stir Until Fully Combined
Mix until the color and texture are completely uniform — no streaks, no swirls. Scrape the sides and bottom of the container with your stir stick; that's where unmixed material likes to hide.
Start Your Timer — Wait 15 Minutes
This is induction time. Set a timer on your phone right now. Don't add reducer yet, and don't spray yet. This waiting period lets the chemical reaction between base and converter get started before you thin it out and put it in a gun.
Add Reducer and Mix Again
Once your timer goes off, add 10–20% reducer (T0006 or T0176) by volume and stir thoroughly. Now you're ready to load the gun.
✓ You're ready to spray when...
- Base and converter are fully combined with no streaks
- The full 15-minute induction time has passed
- Reducer has been added and mixed in
- You're within the 8-hour pot life window (started the clock when you first combined base + converter)
Which Reducer Should You Use?
If you're not sure, T0006 is the safe default for most conditions. Use 10–20% by volume either way.
The standard reducer for High Build in most conditions. Use at 10–20% of total mixed volume. Best for typical temperature ranges (60–90°F). Available at both Rockledge and Stuart locations.
VOC-exempt reducer for North America. When used with D3002, the mixed material comes in under 2.8 lbs/gal VOC. Required in areas with strict VOC regulations. Also suitable for warmer application conditions.
Step 3: Set Up Your Spray Gun
Pick whichever setup matches the equipment you already have. You don't need all three — just dial in the one you've got.
Step 4: Spray It On
This is the part that feels intimidating the first time. Go slow, keep your gun moving, and don't try to get full coverage in one pass.
Verify Environmental Conditions
Check temperature, humidity, and dew point before starting:
- Surface temperature: 55°F (13°C) minimum — 105°F (41°C) maximum
- Ambient temperature: 55°F (13°C) minimum — 105°F (41°C) maximum
- Surface must be at least 5°F (3°C) above dew point
- Do not attempt to cure below 55°F (13°C)
Florida note: During summer (May–October), early morning application (7–10 AM) is recommended to beat rising humidity and surface temperatures.
Mix and Induct
Combine 1 part base (D8002 or D9002) with 1 part D3002 converter. Mix thoroughly until uniform, then wait 15 minutes before adding reducer. Add 10–20% T0006 or T0176 reducer and mix again. Do not skip induction time.
Apply First Coat
Spray even, overlapping passes at 8–10 mils (200–250 microns) wet film thickness. Maintain consistent gun distance and speed. Do not apply to surfaces warmer than 105°F or colder than 55°F. Each coat yields 4–5 mils dry film thickness.
Recoat Window (Within Self)
High Build can be recoated with itself after 2 hours. The maximum no-sand recoat window is 24 hours — after 24 hours, sand before applying additional coats. Apply 2–3 coats total depending on the filling needed. Do not apply more than 2 coats without allowing to cure hard (12–24 hours).
Allow Full Cure Before Overcoating With Other Products
When overcoating High Build with other products (545 Epoxy Primer, Ultra Build, Sprayable Fairing Compound, Awlfair LW, or Awlquik), allow 12–24 hours cure time. Sanding before overcoating with other products is strongly recommended for best adhesion.
Sand and Finish Prime
After High Build has fully cured, block sand with 120–180 grit to achieve a smooth, fair surface. Blow off dust, re-wipe with Awlprep T0008, and apply 545 Epoxy Primer as the finish prime coat before topcoating.
✓ You're done with High Build when...
- You've applied 2–3 coats and the surface is smooth and free of visible texture or low spots
- The final coat has cured at least 12–24 hours
- You've block sanded with 120–180 grit and the surface feels uniform
- Dust is fully removed and the surface is ready for 545 Epoxy Primer as the finish prime coat
"How Long Do I Wait?" — Recoat Cheat Sheet
Bookmark this table. All windows assume 77°F (25°C), 50% RH. Warmer temps shorten these windows; cooler temps stretch them out.
| Scenario | Minimum Wait | Notes |
|---|---|---|
| High Build over High Build | 2 hours | No sanding required within 24-hour window |
| High Build over High Build (max no-sand) | — | 24 hours maximum. Sand if beyond 24 hours. |
| High Build → 545 Epoxy Primer | 12–24 hours | Sand first. Sanding always recommended before overcoating. |
| High Build → Ultra Build | 12–24 hours | Sand first. |
| High Build → Sprayable Fairing Compound | 12–24 hours | Sand first. |
| High Build → Awlfair LW | 12–24 hours | Sand first. |
| High Build → Awlquik | 12–24 hours | Sand first. |
| Max coats before cure break | — | Do not apply more than 2 coats without allowing to cure hard (12–24 hours) |
VOC Info (If Your Area Has Restrictions)
If you've never had to think about VOC limits before — some areas restrict how much solvent can be in your mixed paint. Here's the reference data in case you need it.
| Component | Code | VOC |
|---|---|---|
| Off White Base | D8002 | 347 g/lt (2.9 lbs/gal) |
| Yellow Base | D9002 | 338 g/lt (2.8 lbs/gal) |
| Converter | D3002 | 361 g/lt (3.0 lbs/gal) — 331 g/lt (2.8 lbs/gal) NA only |
| Standard Reducer | T0006 | — |
| VOC Exempt Reducer (NA only) | T0176 | VOC Exempt (NA legislation) |
How Much Should You Buy?
Use this to estimate quantities before you check out — nobody wants to make a second trip mid-job.
@ 1 mil DFT (theoretical)
Recommended (2 coats)
Per Coat
Per Coat
Required
Assumed in Coverage
Coverage is calculated at theoretical 100% transfer efficiency. Actual coverage will vary based on equipment, technique, part geometry, and environmental conditions. Overspray loss of 20–40% is typical in real-world applications.
Questions First-Timers Ask Us
These are the actual questions we get at the counter in Rockledge and Stuart — not just textbook FAQs.
It's a reasonable place to start if you've done basic spray work before (even rattle-can or single-stage paint) and you're comfortable following a timed mixing procedure. The forgiving part is that High Build hides under other coats — minor texture or thickness variation here gets sanded out before topcoat, so it's lower-stakes than spraying a finish color. If you've genuinely never used a spray gun at all, practice on a scrap panel with a cheap primer first to get comfortable with gun distance and pass speed before committing real material to your project.
No. Awlgrip High Build Epoxy Primer is rated for above-waterline use only. It is not designed or tested for immersion service. For below-waterline primer work in an Awlgrip system, consult the full system guide or contact us for guidance on appropriate products.
High Build can be applied directly to properly prepared fiberglass or wood, but Awlgrip strongly recommends sealing those surfaces with 545 Epoxy Primer first for best results. The 545 provides better adhesion to the substrate and gives the High Build a consistent base to build on. Over fairing compounds, no 545 seal coat is typically needed — go straight to High Build.
545 is a versatile epoxy primer that can be sprayed, brushed, or rolled, and it works both above and below the waterline. It provides excellent adhesion and corrosion resistance but relatively thin dry film builds (2–3 mils per coat). High Build is strictly spray-applied, above waterline only, but delivers much thicker film builds (4–5 mils dry per coat) and significantly more filling power. High Build goes on before 545 in a full system — it fills and surfaces, then 545 finish-primes before topcoat.
The 15-minute induction time allows the base and converter to begin reacting chemically before application. This pre-reaction primes the crosslinking process and can improve film formation, flow, and adhesion. Skipping induction time risks applying a material that hasn't fully begun to activate, which can lead to soft films, adhesion failures, or inconsistent cure. Set a timer — 15 minutes, every batch.
No. Awlgrip explicitly states that High Build Epoxy Primer is not recommended for roll-and-tip application. The product's high build properties and viscosity require pressure-fed spray equipment to achieve proper atomization, film thickness, and leveling. Attempting to roll this product will result in an unacceptable film. If you need a fill primer that can be rolled, contact us — we can discuss alternative products.
Do not apply more than 2 coats of High Build without allowing the material to cure hard — which takes 12–24 hours. Stacking too many coats before a cure break can trap solvent, cause wrinkling, or result in soft film failure. Apply 2 coats, let it cure overnight, then assess whether a third coat is needed before sanding.
Yes. T0176 is the VOC-exempt reducer approved for North America. It is a medium-evaporating reducer suitable for most standard conditions and is specifically required when formulating the mixed material to meet low-VOC thresholds (under 2.8 lbs/gal). Both reducers are interchangeable for most applications — T0176 is the preferred choice in VOC-regulated areas. T0006 is the standard reducer for general use.
Sand High Build with 120–180 grit paper before overcoating with 545 Epoxy Primer. After sanding, blow off dust with clean compressed air, dry-wipe with clean rags, and wipe with Awlprep T0008 before applying 545. Do not leave sanding scratches coarser than 180 grit under 545 — they can telegraph through the final topcoat, especially under dark colors.
D8002 is the off-white base and D9002 is the yellow base. Both use the same D3002 converter and have essentially the same performance characteristics. The choice is primarily about what color is easiest to sand-through and visually assess when block sanding your high build coats. Some painters prefer yellow because it contrasts clearly with the grey or white of fairing compound below. Both are in stock at our Rockledge and Stuart locations.
Ready to Order High Build Epoxy Primer?
Both Rockledge and Stuart locations carry D8002, D9002, D3002, T0006, and T0176 in-stock. Call us or visit — we'll help you spec the right quantities for your project.
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