Fisheyes are crater-like defects that form when contamination, most often silicone, oil or leftover wax, stops wet paint from flowing across the surface. Before you change anything else, run three checks: review how the panel was prepped, test the compressed air through a clean gun, and inspect the booth intake and filters for bypass or poor fit.
TL;DR:
- Test a freshly prepped control panel after each diagnostic change; if defects follow different vehicles, investigate the booth or air system rather than one panel.
- Use wax and grease remover while wet, discard each lint free cloth after one wipe, and ban silicone aerosols near paint areas.
- For wet basecoat, let the coat flash before a light mist coat; reserve fisheye eliminator for approved topcoats, since it cannot replace cleaning.
- Replace filter media uniformly and inspect seals, secondary intakes, and pressure, because bypass can draw unfiltered shop air into the booth.
Table of Contents
- What do fisheyes look like in wet and cured paint?
- What causes fisheyes in paint?
- How do you trace the source of fisheyes step by step?
- How do you prevent fisheyes from coming back?
- How do you fix fisheyes in wet and cured paint?
- What can filters realistically do about airborne silicone?
- Why does silicone cause fisheyes?
- How do humidity and temperature affect fisheye formation?
- How should you handle and store paint and consumables?
- How do fisheyes differ between basecoat and clearcoat?
- How do booth airflow and ventilation design prevent fisheyes?
- What should a routine booth inspection cover beyond filters and air lines?
- How do fisheyes differ from solvent pop and other defects?
- How do you isolate recurring contamination?
- What surprises technicians most about silicone in a shop?
- How can protective booth films support a fisheye prevention routine?
- FAQ
- Sources
What do fisheyes look like in wet and cured paint?
Fisheyes show up as small round craters where the film pulls away from a contaminated spot, often leaving a glossy ring or a donut shape. WERCS Inc describes typical sizes of 1â6 mm. They usually appear while you are spraying or within minutes afterward, while the film is still wet enough to move.
Quick visual tests help you avoid misdiagnosis:
- Look for clustering in one area of a panel, which points to a local contaminant such as a fingerprint or detailing residue.
- Compare the pattern with airflow and spray direction. Defects that follow your gun path suggest contaminated air or gun parts.
- Check what sits at the bottom of the crater. Fisheyes often expose the primer or substrate underneath.
- Scattered, tiny pinholes with no exposed substrate are a different problem, covered later in this article.
What causes fisheyes in paint?
Work through the sources in order of likelihood. Eastwoodâs guide names silicone products, residual wax and grease, oil or moisture in compressed air, and cross-contamination from clothing or tools as the most common culprits.
- Silicone products: detail sprays, polishes and tire dressings lead the list, even when used well away from the booth.
- Residual wax or polish: wax, polish or prep solvent left to dry on the panel instead of being wiped off wet.
- Oil contamination: skin oils from bare hands, greasy tools, or compressor oil and moisture carried through the air lines.
- Material and equipment contamination: dirty mix cups, strainers, or gun parts.
- Cross-contamination: work clothes, aerosols used elsewhere in the shop, and poor masking that lets residue transfer onto the panel.
One source breaks the contamination down as 50% painter, 40% booth and 10% vehicle, according to Eastwoodâs guide. Treat that as one practitionerâs split, but it makes a useful point: most of what you can fix is under your control, not on the vehicle.
How do you trace the source of fisheyes step by step?
Start upstream and work outward. Panel first, then air and gun, then the booth itself. This order saves you from replacing expensive filters when a wiped-on residue was the real cause.
- Check the panel. Review the prep history, any recent detailing, and which tack cloths and solvents were used. Re-clean a small test area with fresh solvent and a clean cloth, then spray it.
- Check air and gun. Drain the compressor tank and replace inline filters. Run the air through a clean gun and spray a test panel that you know was prepped properly.
- Check the booth. Inspect intake and ceiling filters for gaps, bypass paths and uneven loading. Aeroflow Filters recommends checking intake and pre-filters first, then ceiling or plenum media, because poor fit commonly lets outside contamination in.
- Compare across jobs. Spray different vehicles with different prep histories. If the defect follows the booth or air on every job, the cause is not the panel. If it follows one vehicle, it is panel-specific.
Pro Tip: Spray a clean, freshly prepped test panel on every diagnostic pass so you always have a control to compare against.
How do you prevent fisheyes from coming back?
Prevention is a set of shop habits, not a single product. Dropletlab names rigorous surface prep, single-use lint-free cloths and compressed air maintenance as the primary elimination methods.
- Apply wax-and-grease remover wet, keep it wet while you wipe, and never let it dry on the panel.
- Use a fresh lint-free cloth for each wipe and discard it.
- Wear lint-free suits and gloves to keep skin oils and sweat off the work.
- Ban silicone aerosols near the paint area, and separate detailing and paint zones.
- Drain air tanks daily and keep filters and receiver-dryers on a schedule. Our booth maintenance guide covers filter and air-system checks in more detail.
- Replace filter media across a position together so airflow stays even, and look for secondary intakes or leaks.
Pro Tip: Write the cleaning protocol on a card at the prep station so every technician follows the same wipe-wet, wipe-dry sequence.
How do you fix fisheyes in wet and cured paint?
What you do depends on whether the film is wet or cured.
- Stop spraying as soon as you see defects in the wet film, and let the coat flash. Small defects can sometimes bridge with a light follow-up coat, as STM Coatech notes for basecoat.
- Remove wet paint if the contamination is heavy, then clean and refinish, per Sherwin-Williams guidance.
- Sand cured defects until the crater edges and any contaminated film are gone.
- Re-clean thoroughly with the correct solvent and fresh cloths before you refinish.
- Use fisheye eliminator sparingly. It may help in some topcoats, but Dropletlab warns against using it in basecoats or undercoats, and it can mask poor prep. It never replaces cleaning.
- Service the equipment if defects recur on properly prepped panels: clean or rebuild the gun and service the air lines.
What can filters realistically do about airborne silicone?
Less than most shops hope. Vichem points out that new filters do not fix silicone already on a panel or in the spray lines, so changing media before checking prep and air wastes time.
- Diagnose in order: panel first, because filters cannot lift contamination that is already on the surface.
- Replace media uniformly and check fit, since unevenly loaded filters or bypass points give inconsistent results.
- Treat protective films as one more layer that captures settled contamination alongside cleaning and filtration, not as a cure.
Why does silicone cause fisheyes?
Silicone has very low surface tension, much lower than the paint sitting on top of it. When wet paint meets a silicone-contaminated spot, the paint is pulled away from the low-tension area toward the surrounding higher-tension film. The result is a crater with a raised rim, and often the substrate showing at the center.
Two other properties make silicone hard to deal with. It is highly mobile: Eastwood notes that even products used away from the booth can travel through shop air and land on panels, producing defects that look unrelated to the jobâs prep history. And it clings. Axaltaâs defects manual advises that many silicones adhere firmly and may not come off with routine solvent wiping, so severe cases call for extra cleaning and, sometimes, booth decontamination and replacing contaminated media.
This is why a single wipe is rarely enough on a panel with suspect history. Wiping with a dirty cloth or a half-dry solvent can spread silicone around instead of removing it. Fresh solvent, fresh cloths and a wet-wipe, dry-wipe rhythm are the practical answer, and why silicone-bearing aerosols deserve their own rules in any shop that sprays.
How do humidity and temperature affect fisheye formation?
Humidity and temperature do not create fisheyes on their own. They change how contamination behaves. Our sourced material does not give a humidity or temperature threshold for fisheyes, so treat the following as shop reasoning rather than a rule.
High humidity raises the moisture load in compressed air. Water carried through the lines can bring compressor oil with it, so a humid day may expose an air system that was already marginal. That is one reason daily tank drains and regular filter and receiver-dryer service matter most when the weather is damp.
Temperature affects solvent behavior. Cold panels or cold booth air slow solvent evaporation, which gives contaminants more time to move and spread in the wet film. Hot conditions can make a cleaning solvent flash off before you wipe it, leaving the dissolved contaminant behind on the panel. Axaltaâs Prevent Cratering! bulletin also recommends working in low air-movement conditions, which matters when drafts carry contamination onto the panel.
The practical takeaway: if fisheyes appear on a humid or unusually hot or cold day and vanish on a mild one, look hard at your air system and your solvent wipe technique before blaming the paint.
How should you handle and store paint and consumables?
Contamination often starts before the gun is loaded. Treat every consumable as a potential carrier.
Keep paint, thinners, reducers and strainers in a clean, enclosed area away from detailing products and silicone-bearing aerosols. Dropletlab describes aerosol detailers, dressings and lubricants as high-risk âfisheye bombsâ because residues and airborne droplets travel through shop ventilation. Storing them in the same room as your paint supplies invites trouble.
Handle mix cups, sticks and strainers by their outsides, and keep lids on anything you are not actively using. Cover opened containers rather than leaving them exposed to shop air. If a container or tool has touched a suspect product, retire it rather than rinsing and hoping.
Cloths and tack cloths deserve the same discipline. Store lint-free wipes sealed so they do not pick up airborne residue, and use each one once. Keep gloves in a clean dispenser, not in a pocket that also holds a can of silicone spray.
Finally, label and separate. A clearly marked âpaint zone onlyâ shelf, with a rule that no silicone product crosses the line, is a cheap control that pays for itself the first time it prevents a respray. For a broader checklist, see our contamination prevention guide.
How do fisheyes differ between basecoat and clearcoat?
Fisheyes can hit any layer, but the repair path changes with the coating. Basecoat is the more delicate case. Dropletlab says fisheye eliminator additives should not go into basecoats or undercoats. For minor defects in basecoat, STM Coatech notes that letting the coat flash and then mist-coating can bridge small fisheyes.
Clearcoat is where eliminator additives are most often discussed, and where Sherwin-Williams says to add them only per the productâs own guidance. Even there, the additive is a limited tool. If you reach for it every job, the underlying prep or air problem is still unsolved.
One practical difference: contamination that lands between coats gets locked in. A clean basecoat can pick up airborne silicone while it flashes, and then the clear craters over it. If defects only appear after the clear goes on, check what the panel was exposed to during the flash window, not just what happened at prep.
Whatever the layer, the rule from the earlier sections holds: find and remove the contaminant first, then refinish. Additives and mist coats are bandages, not cures.
How do booth airflow and ventilation design prevent fisheyes?
Booth airflow decides where contamination goes after it enters. Intake filters are the first gate, and Aeroflow Filters notes that fisheyes often point to outside contamination entering through an unfiltered intake or a seal failure. A gap around a filter frame is an open door for silicone-laden air.
Uneven loading matters too. When some filters in a position are clogged and others are fresh, air takes the path of least resistance, which can pull unfiltered air through weak spots and create variable results across a panel. Replacing media across a position together keeps flow even.
Look beyond the filter bank. Secondary intakes, door gaps, open vents and negative pressure relative to the shop can all pull in shop air that never touched a filter. If your booth sits near a detailing bay or a lube area, that unfiltered air may carry exactly the contaminants you are fighting.
Airflow patterns also determine whether settled contamination gets stirred back up. Dust and residue that collect on walls and floors can be disturbed by movement and traffic. Our guidance on booth dust control methods covers filter fit and airflow in more detail.
We also manufacture multi-layer wall and floor films that capture settled particles, so each removable layer takes surface contamination away instead of leaving it to be disturbed. They sit alongside, not in place of, good filtration and ventilation.
What should a routine booth inspection cover beyond filters and air lines?
Filters and air lines get the attention, but the rest of the booth can hold contamination too. Autobody News lists frequent failures: dirty filters, missing PPE, poor gun maintenance, sanding in the booth and old air hoses. Build your routine inspection around those and add the surfaces nobody wipes.
Walk the booth with a checklist:
- Walls and floor: look for overspray buildup, residue and anything that can flake or be disturbed.
- Door seals and gaskets: check for gaps that let shop air in.
- Lighting fixtures and lenses: wipe them down, since residue collects on glass.
- Hoses and fittings: replace old or poor-quality hoses and check connections for leaks.
- Gun storage and cleaning area: confirm it is separate from prep chemicals.
- Masking materials and tape: store them clean and use fresh stock.
- Floor and wall protection: confirm films or coverings are intact and layers are fresh.
- Booth contents: remove anything that does not belong, especially aerosols and rags.
- Personnel habits: confirm technicians suit up before entering and no sanding happens inside the booth.
Our protection guide adds practical steps that complement this list. Run the inspection on a set schedule, log what you find, and compare the log whenever defects return. A pattern in the log is often the fastest route to the source.
How do fisheyes differ from solvent pop and other defects?
Misdiagnosis is expensive, so separate these defects before you repair anything. Eastwoodâs guide covers fisheyes and solvent pop in the same article because they are so often confused, even though the causes differ.
Fisheyes are craters caused by surface contamination repelling wet paint. They often expose the substrate and can show a glossy ring. Solvent pop is a different mechanism: trapped solvent escapes through a film that has begun to skin over, leaving tiny pinholes or blisters. Pop tends to cluster where the film is thick or where flash time was too short, not around a contaminant.
Dust nibs are the third common confusion. These are small raised bumps from particles landing in the wet film. Aeroflow Filters says dust nibs usually point to intake or ceiling filter bypass or loaded media, while fisheyes often indicate external contamination entering through an unfiltered intake or a seal failure. Different defects can share the same root area, but they are not the same symptom.
A quick sort: raised bump, think dust. Tiny pinhole or blister in a thick area, think solvent pop. Round crater with exposed substrate or a ring, think contamination. When a defect fits two descriptions, look at pattern and location before you grab sandpaper.
How do you isolate recurring contamination?
Recurring fisheyes mean the source is still active. Use a repeatable process rather than changing several things at once.
First, change one variable at a time. If you replace filters, drain the air system and switch solvents on the same day, you will not know which one mattered. Make one change, spray a test panel, and record the result.
Second, use the cross-job test. Vichem notes that a key diagnostic is whether fisheyes appear across different jobs. If they do, suspect the booth or air rather than panel contamination. If one vehicle is the only problem, the answer is likely in its history.
Third, keep a log: date, vehicle, prep products, weather, who sprayed, which gun, and what defects appeared. Patterns emerge quickly. A defect that always follows one technician points to PPE or habits. One that follows a particular day of the week may trace to detailing activity in the shop.
Fourth, ask where silicone could come from, not whether it is there. Eastwoodâs guide notes that products used away from the booth can still end up on panels, so look at the whole building, not just the booth.
Finally, bring in a partner who understands the cleaning side. Residue from products such as spray and rinse coatings is worth reviewing when you audit what gets used near paint work.
What surprises technicians most about silicone in a shop?
In my experience, the surprise is distance. Technicians hunt through the booth and the air system, while the silicone came from a detailing or body-shop task done across the building. It is rarely where you expect it, and it is almost never a single event.
My rule is simple: fix prep and air first, and treat everything else as secondary.
â Pavlos - Angelos Filippakis
How can protective booth films support a fisheye prevention routine?
Films will not cure a bad prep routine, but they can cut the contamination that settles in your booth and the time spent cleaning it. We make the Multiple-Layer Spray Booth Wall Protector and Floor Protector with electrostatic and tacky surfaces, removable layers, tape-free seams and resistance to heat. Ask us about bulk and custom orders.
FAQ
What are the most common causes of fisheyes in paint?
Surface contamination is the usual cause: silicone products, residual wax or grease, oil or moisture in compressed air, and cross-contamination from clothing or tools. Eastwoodâs guide lists these as the most common sources. Silicone leads the list.
How can I fix fisheyes in my paint?
For wet film, stop spraying, let the coat flash and inspect, since small defects can sometimes bridge with a light coat. For cured defects, sand the area, re-clean thoroughly and refinish. Dropletlab lists these repair steps.
What is the most effective way to eliminate fisheyes?
Rigorous surface preparation is the primary method: remove wax and grease with the right solvent, wipe with single-use lint-free cloths and maintain your compressed air system. Dropletlab says additives may help in some topcoats but cannot replace correct cleaning.
What are fisheyes typically caused by?
Fisheyes form when a contaminant such as silicone, oil or wax repels wet paint and leaves a crater. Sherwin-Williams lists oil, wax and silicone, and using thinner as a cleaner, among the causes. Contaminated air and poor prep are the usual routes.
Sources
- How to Prevent and Fix Fisheyes or Solvent Pop In Paint Jobs - The Garageâą
- Fisheye Paint Defect: How to Prevent Coating Craters
- Spray Booth Paint Defects: Is Your Filter the Cause?