If you want your clear coat to have an ultra smooth, glossy, professional finish, choosing the right spray nozzle size is crucial.
In this guide, as a professional spray nozzles supplier, I’ll explain everything you need to know about picking the perfect nozzle size when spraying automotive clear coat.
Why Clear Coat Nozzle Size Matters?
Many DIYers underestimate the importance of spray nozzle size selection when applying clear coats.
But the nozzle size has a huge impact on clear coat atomization and flow rate, which directly affects the final finish quality.
Get the size wrong, and you’ll likely end up with an uneven finish plagued by orange peel or runs.
However, when armed with the right knowledge, dialing in the ideal nozzle size for your clear coating project is not overly difficult.
Keep reading and I’ll walk you through how to select the perfect nozzle to take your clear coating results to an incredible new level.
What Size Nozzle To Use For Clear Coat?
Most automotive clear coats work best with a nozzle size in the 1.2 to 1.5 mm range.
Within this range:
- 1.2 mm nozzles are suitable for overall smoothness and fine finish work
- 1.3 – 1.4 mm nozzles provide great all-round clear coat atomization
- 1.5 mm is ideal for covering large surface areas efficiently
However, always defer to your clear coat’s technical specifications for the recommended nozzle size.
Some specialist clear coats are designed to be sprayed with smaller or larger nozzle sizes outside of this range.
Other Factors To Consider
Choosing the nozzle size is about more than just matching the number on the technical specs sheet.
To hone in on the optimal nozzle size, also consider:
Clear Coat Viscosity
Higher viscosity clear coats require larger nozzles, while thinner clears need smaller nozzles.
Using too small of a tip with a thicker clear will result in poor breakup and flow, causing texture issues.
Application Method
Your spraying technique and pass method also influences ideal nozzle sizing.
Wet coats using slower passes suit smaller nozzles around 1.2 mm, while faster spray techniques work better with larger 1.4 – 1.5 mm nozzles.
Number of Coats
Applying single, thicker coats allows larger nozzles.
But when spraying multiple thinner coats, smaller nozzle sizes around 1.2 – 1.3 mm provide superior results.
Environmental Conditions
In higher temperatures, clear coats become less viscous, allowing the use of smaller nozzle sizes.
But with lower ambient temperatures, the increased viscosity means moving up to larger nozzle sizes.
Surface Area and Shape
For smaller, intricate areas, smaller nozzles provide precision.
But when covering expansive surface areas, larger nozzles up to 1.5 mm improve efficiency.
How Nozzle Size Impacts Clear Coat Finish
The nozzle size impacts clear coat atomization, flow rate, and overall finish quality.
Atomization
Smaller nozzles create a finer clear coat mist, while larger nozzles decrease atomization.
Too small of a nozzle can dry spray the clear coat before it reaches the surface.
But larger nozzles have insufficient atomization, causing texture issues.
Flow Rate
Smaller nozzles also greatly reduce the clear coat flow rate.
While increased flow from larger nozzles speeds up application, it can also cause sagging and runs.
Finish Quality
In most cases, nozzle sizes in the 1.2 – 1.4 mm range provide the best all-around finish results.
The fine atomization prevents drying, minimizing texture issues like orange peel.
And the lower flow rate allows the clear coat to spread evenly before drying, creating a smooth finish.
How To Calculate Spray Nozzle Size
Whether you’re looking for optimized coverage, maximum gloss levels or the fastest application method, use these tips to dial in perfection:
Check Technical Recommendations
Always start by checking the clear coat’s technical data sheet for the manufacturer’s recommended nozzle size.
This provides an excellent baseline setting to fine tune from.
Consider Viscosity
Higher viscosity clears demand larger nozzles for adequate breakup.
If spraying a thicker clear coat, test a nozzle size 0.2 – 0.3 mm above specifications.
Account for Ambient Conditions
Adjust nozzle size based on current temperature and humidity levels.
In warmer spraying conditions, smaller nozzles work great with thin clears.
But when it’s cooler out, compensate by increasing nozzle size.
Test Cards Are Your Friend
There’s no better method than testing on spray cards to dial in perfection.
Experiment with different nozzle sizes while keeping distance and pressure constant.
Once you see optimum atomization without drying or running, you found spray gun nirvana.
FAQs – Nozzle Sizes for Clear Coating
Still hungry for more spray nozzle clarity to take on your clear coating challenges with confidence?
Check out these common clear coating nozzle questions:
Should I Use a 1.2, 1.3 or 1.4 Nozzle Tip For Clear Coat?
For most clear coating tasks, 1.3 to 1.4 mm nozzles provide the best all-around results.
The fine atomization prevents drying spray texture issues, while maintaining enough flow rate for efficient leveling.
However, smaller 1.2 mm or larger 1.5 mm nozzles may be better for specific applications.
What Size Nozzle Should I Avoid For Clear Coat?
Avoid using nozzles smaller than 1.0mm or larger than 1.8mm for clear coats.
Extremely small nozzles often dry spray clear coats before they reach the surface.
And oversized nozzles have insufficient atomization, preventing proper flow out.
Can I Spray Clear Coat With a 2.0 mm Nozzle?
It’s generally not recommended to spray clear coats with nozzles as large as 2.0mm.
Oversized nozzles like these lack the required atomization, which can cause texture issues in clears.
Stick to your clear coat’s recommended nozzle size specifications for best results.
Wrap Up
Choosing the optimal nozzle size transforms the clarity and gloss levels of your clear coated finishes from mundane to magnificent.
While the ideal nozzle size depends on several factors, most clears work exceptionally well in the 1.2 to 1.5 mm range.
If in doubt, always defer to your product’s technical data sheet for a recommended starting point.
From there, fine tune based on ambient conditions, personal spraying technique and test cards.
Once dialed in correctly for your unique project, prepare for crystal clear coat bliss.
So don’t shy away from one of the most important – yet often overlooked – settings on your spray gun.
Equipped with the knowledge in this guide, selecting the perfect nozzle size for superior clear coat finishes is now well within your reach.