The fiberglass pool shell is the foundation of the entire pool project. We have made it our mission to partner with a manufacturer that is able to produce a pool you can rely on for many years, even decades, into the future. 

What is Cross-Lynx?

Cross-Lynx is a series of cutting-edge materials and manufacturing best practices that ensure you have the strongest, most durable fiberglass pool possible. Without getting too technical, the core premise of Cross-Lynx is to drive a process called polymerization during the manufacturing process. Polymerization is the process by which polymer molecules cross-link together to form a web of strength within each layer of the shell structure. Each layer of each fiberglass pool undergoes this polymerization process. The more cross-linking that occurs, the stronger and more corrosion-resistant the pool shell becomes. Cross-Lynx Composite Technology was created to fuse the entire structure together, layer by layer, into a single composite structure that's incredibly strong and durable.

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Layers of Cross-Lynx Composite Technology

1. Gelcoat Surface Layer
The entire surface of the pool that we see and touch is a thin layer of gelcoat. Because fiberglass pools are actually built from the inside out, gelcoat is the first layer applied during the manufacturing process. Our gelcoat is spray-applied to a thickness of 27 to 30 mils and provides the rich color and smooth finish that make fiberglass pools beautiful and user-friendly.
You have probably heard that fiberglass pools are easier to maintain than traditional pools. This is because the gelcoat surface is relatively nonporous. This makes the pool algae-resistant and eliminates the need for burdensome maintenance like brushing the entire pool each week or costly acid washing every 3-5 years to kill embedded algae.
It’s important to us that our gelcoat achieves a proper cure, as this will ensure its durability.
If you read enough online forums about fiberglass pool gelcoat, you’ll find some people, especially with older white pools, had problems with their pool surfaces eroding away. The surface would “chalk” and turn to white powder before their eyes. The surface of these pools was deteriorating. In some cases, this was most assuredly due to homeowner neglect, but in many cases the gelcoat never achieved a full cure.
This deterioration could be for a number of reasons such as:

  • Improper factory conditions
  • The gelcoat was under-catalyzed
  • The gelcoat was not backed by another layer of laminate to drive the cure
  • To prevent this from happening, we go to great measures to ensure that not only our gelcoat but all the layers of our pool shell achieve maximum polymerization. 

With as many polymer chains cross-linked as possible, the product reaches a full cure with maximum strength and durability. One key to making this happen is temperature, because heat drives the cross-linking process.

2. Vinyl Ester Resin for Blister and Corrosion Resistance
The second layer of the fiberglass pool manufacturing process is our vinyl ester chopped fiberglass layer. Vinyl ester is a premium-grade resin specifically blended to prevent an unwanted process called osmotic blistering—a phenomenon where the gelcoat surface forms actual blisters and separates from the next laminate layer. Water travels through the gelcoat, comes in contact with other contaminants, and forms a larger molecule. The larger molecule then tries to exit the same way it came in. This causes an outward force on the gelcoat, eventually resulting in a blister. Vinyl ester resin prevents this from happening because it acts as a watertight barrier. The water passes through the gelcoat, contacts the pure water barrier, and then leaves. A huge variety of blended vinyl esters are available to composites manufacturers, and truth be told, it only takes a small percentage of vinyl ester to call a product “vinyl ester resin.” Our vinyl ester is specially blended to produce the best blister protection available. 
A second advantage to our vinyl ester chopped fiberglass layer is that it helps drive the cure of the gelcoat. As soon as the gelcoat has set, we apply this layer of chopped fiberglass that serves as a gigantic heating blanket.
The beauty of our Cross-Lynx Composite Technology is that the exothermic heat (called exotherm for short) generated from the curing process of each layer actually helps drive the cure and cross-linking process of all previous layers. Talk about synergy!

3. Chopped Fiberglass for Strength
Now that we have our gelcoat surface applied and our corrosion and blister resistance covered, it’s time to start building the strength of the pool shell. We apply chopped fiberglass by a “chopper gun” that simultaneously chops continuous strands of glass fiber into roughly 1” pieces while spraying resin and catalyst all onto the mold. We then roll it out to consolidate and remove air.
 
Why Do We Use Chopped Fiberglass vs. Hand-Laid Fiberglass to Build Strength?
We have done it both ways, and we prefer chopped fiberglass for several reasons:

  • Chopped glass actually gives the pool the perfect balance of flex and strength. We have found that pools that are more hand-laid than chopped are actually more flexible than we prefer. The pool needs to be strong enough to lift, transport, and set, and also rigid enough to hold its shape. We feel that chopped fiberglass in bulk strikes that perfect balance.
  • One of the disadvantages of chopped fiberglass from a manufacturing standpoint is that it requires a lot of skill to produce a consistent thickness. In contrast, hand-laid woven roving has a set weight and thickness so it’s easier to manage material use. However, because our fiberglass specialists are highly skilled and we keep the same teams year after year, we don’t have a problem with consistency. This is evident by the cut-outs from every pool that show the true pool thickness and the fact that we weigh each and every pool as an internal quality control measure.

4. Hand-Laid Woven Roving at Stress Points
Specific areas of the pool shell are subject to higher levels of flexural stress. Think where the pool floor meets the walls, tanning ledges, steps, and benches. We reinforce these areas with this added layer of woven roving fiberglass for additional strength.

5. Structural Comb Supports
Fiberglass is naturally flexible. In fact, its tensile strength is many times that of concrete. But there are times where we want it to stay put. Consequently, we use structural comb ribs and support layers throughout the pool shell and obtain a much higher strength in these areas with very little material or labor cost. We use structural comb supports under the entire surface of all steps, benches, and tanning ledges. We also use structural comb ribs along the side walls of the pool.

6. Final Chopped Fiberglass Strength Layer
The fiberglass pool manufacturing crescendo is a final layer of chopped fiberglass to provide even more strength. The exotherm from this layer is the final heat blanket that will continue to drive the cross-linkingprocess of all previous layers to a full cure. While adding this layer, we also glass-in the lifting points on the pool.

That concludes the manufacturing of the pool shell. Next, the pool is removed from the mold, trimmed, and detailed.