A face coating does two opposite things at the same time. It holds the grit particles in place, and it buries the tips that do the gripping. The final result depends on when the grit was applied.
The Short Answer: One Knob, Two Directions
Resin depth over the grit works like one knob.
A thicker layer holds the particles in place longer, and it also lowers both the roughness reading and the grip. A thinner layer leaves more of each tip standing above the surface, so grip rises. The same particles then sit close to the surface, where they can break off.
A coating is neither good nor bad on its own. It is a setting, and the setting has to match the job.
What a Coating Layer Does to the Grit Under It
A coating is resin laid over grit that is already there.
That layer changes one thing that matters: how much of each particle stands above the surface. The exposed tip is what the ball touches. If the tip is buried, the face reads smooth whatever sand sits underneath.
A thin layer leaves more of each tip above the surface, and a thick layer leaves less.
Two faces can look alike in a photo and be built in opposite ways. Paddletek sells the Bantam TS-5 Pro with a UV-coated textured fiberglass face. JOOLA sells the Dash with a sandblasted surface.
Half-Cured Resin: Where Grit Sinks In
This is the part most spec sheets miss.
If grit is applied while the resin is still soft, particles settle into the surface. The resin then cures around them and locks them in place. Wear has to remove resin before it can reach the particle.
If grit is applied after the resin has cured, particles sit on top. Initial grip is higher because the tips are fully exposed. Wear reaches them sooner.
One build, two results, and the only difference is the timing of one press. Our own faces use the first route: how ceramic grit is anchored in the resin.
Texture Depth vs Grit Exposure
Depth and exposure measure two different things, and buyers mix them up constantly.
Texture depth is how deep the press pattern goes. Grit exposure is how far the tips stand above the resin. A deep pattern with fine sand can expose less tip than a shallow pattern with coarse sand.
That is why the words “textured face” on a spec sheet carry very little information. A buyer should ask for the sand grade and the exposure rather than the pattern name.
Why Grit Falls Off: Four Process Variables
Particles break away for four reasons, and all four are controllable.
- Surface energy. Low-energy plastics hold resin poorly unless the surface is treated first.
- Primer. A bonding layer between the face and the resin system. Skipping it lets the whole layer lift.
- Cure window. Too early and grit sinks out of position. Too late and it never bonds.
- Embedding depth. Particles resting on the surface have one contact point. Particles sunk into resin have many.
A face that fails on this list usually does it months later. By then the warranty window has closed on paper, even when the brand still covers the claim.
Surface Energy and Primer: The Step That Decides Adhesion
Low surface energy is the quiet cause of most grit loss.
A surface that repels resin cannot bond to it. The fix is mechanical or electrical. A light abrasion opens the surface. A corona treatment raises its energy before coating.
Then comes the primer. It sits between the face and the resin system and gives both sides something to hold. Skipping this step saves one pass through the line and costs a batch later.
The Cure Window: Where Grit Gets Locked In or Left Loose
Each resin system has a cure window, and that window can be narrow.
Grit that goes on before the window opens sinks deeper than intended, which lowers grip. Grit that goes on after the window closes fails to bond, which lowers life. If the window drifts across a shift, two paddles from one batch behave like two different models.
Wide windows are easier to run and harder to differentiate. Narrow windows give the result we want and punish any line that rushes.
What to Write in the Spec: Wet Thickness, Dry Thickness, Coverage
Vague specs produce vague samples. Four values remove most of that ambiguity.
- Wet thickness of the coat as applied.
- Dry thickness after cure, which is the number that matters on the shelf.
- Coverage, meaning full face or a defined zone.
- Sand grade and loading, meaning particle size and how much sand per area.
“The face is textured” describes a look rather than a spec.
Three Side Effects: Weight, Gloss and Roughness
Coating and texture move three numbers that other people are watching.
Property | What moves | Limit or target |
Weight | Coat and grit mass | 225 g ±5 g |
Gloss | Smoothness of the outer layer | ≤ 80 GU at 60° |
Roughness | Exposed tip height | Rz ≤ 30 µm |
The roughness ceiling is a rule rather than a preference. The numbers that count against it are explained in the roughness limits a face has to stay under.
What a Coating Cannot Fix
A thicker coat cannot rescue three common problems.
- A face material that will not bond without treatment. Extra resin over a weak bond still fails.
- A grit that is too soft for the court. Coatings hold particles. They do not harden them.
- A structure problem below the face, such as a poor bond between core and skin.
We also hold one 100-hit comparison run, and that is not a study of coating thickness against grip. No single thickness is correct for every face. We will quote the process window we run and the readings that came out of it.
Order of Operations for a New Face Build
A brand should fix these in order, one decision at a time.
- Face material and its surface treatment.
- Sand grade and loading.
- The point in the cure where grit goes on.
- Coat thickness, wet and dry.
- Graphics and their position.
- Weigh-back and a control face test.
A correct sequence lets one sample answer one question. Three changes in one round leave a sample unreadable.
Why the two face families respond differently is covered in why raw and coated faces wear differently. The wider set of options sits in the four surface finishes. If the face also carries print, the ink side has its own rules, covered in why graphics chip on composite faces.
FAQ
Does a thicker coating mean a longer-lasting face?
It can, up to a point. Past that point the tips stay buried and grip drops.
Is sprayed grit worse than fused grit?
It depends on the build. Sprayed grit starts higher and falls faster. Fused grit starts lower and holds its grip.
Can we get both grip and life?
Partly. A brand should control the exposure instead of chasing maximum roughness, and leave headroom under the limit.
How do we know the grit bonded properly?
It comes off as whole particles rather than powder, and the loss pattern is even across the face.
Does a coating change the paddle weight?
Yes. Weigh the face blank before and after, and keep the finished paddle inside 225 g ±5 g.
Can grit be added after molding instead?
It can, and it becomes a surface layer rather than part of the build. Life is shorter.
What is the biggest cause of grit loss?
Poor bonding. Surface energy and the primer step usually decide it.
Do we need a new sample for a coating change?
Yes. Coat thickness changes both weight and roughness, and both are on the spec.
Final Checklist: Coating and Texture Parameters to Fix Before Sampling
- Face material and its surface treatment chosen
- Mode of treatment agreed: abrasion or corona
- Primer specified, and the pass in the line assigned
- Sand grade and loading written as numbers
- The cure stage for grit application fixed
- Wet and dry coat thickness in the spec
- Coverage area defined
- Weigh-back step added to the sample run
- Roughness and gloss measured on the same sample
Send the list to our engineering team and we will answer every line.