# Reading the signs before a gel coat clear layer cracks at the corner radius Gel coat crazing starts at the corner radius, never in the flat panel. What it looks like at ninety days in an LA County storage lot, why correction at $500 beats refinishing at $6,500, and how tinted gel coat gets ordered. ## Gel coat is a layer of the laminate, not a coating sitting on top of it The call almost always starts as a request for a repaint. An owner walks the front corner of a fiberglass fifth wheel, finds a patch of fine lines that look like the crazed glaze on old pottery, and assumes the paint is coming apart. On most molded coaches there is no paint at all. The outermost eighteen to twenty five mils are pigmented polyester gel coat, sprayed into the mold before a single layer of glass went in, with a thin clear layer over the graphics on newer units. That distinction is the whole article. A coating that fails can be stripped and replaced. Gel coat is a structural skin chemically bonded to the chopped strand and mat behind it, so a crack in the gel coat is a crack in the outside of the laminate. Painting over crazing buries it for one season, then the lines telegraph straight through the new film. It is the most common failed previous repair we find on front and rear caps. The second thing owners get wrong is where to look. The flat expanse of a sidewall rarely crazes first. The corner radius does, nearly every time, because a radius is where the laminate changes direction and where the gel coat pooled thickest when the part came out of the mold. ## What ninety days in a storage lot actually leaves behind The first stage is invisible from ten feet. It is a dulling that follows the curve of the radius and nothing else, a band an inch or so wide where the surface has gone slightly matte while the panel beside it still holds gloss. Wash the coach and the band stays dull. That is oxidation concentrating exactly where the resin is thickest and runs hottest in the afternoon. Stage two is crazing you can only see at a low angle with the sun behind your shoulder. Fine lines, one to three inches long, roughly parallel to each other and running perpendicular to the run of the radius. Drag a fingernail across them and nothing catches, because at this point the cracks are still inside the gel coat and have not broken the surface. Stage three is a crack a nail does catch, usually one dominant line with shorter branches off it, and it usually starts at a molding screw, a fastener, or the cut edge of a decal. Once a nail catches, water has a path into the laminate behind the skin, and the question stops being cosmetic. ## Heat, UV and a radius that concentrates every cycle An owner storing a coach outdoors in LA County is running an accelerated aging test without meaning to. A white cap in an open gravel lot in the San Gabriel Valley reaches surface temperatures far above ambient on a July afternoon and gives back thirty five to forty degrees overnight, every night, from May into October. Add the UV load at this latitude with no cover over the roofline. The radius is preloaded before any of that happens. Thicker gel coat in a corner means more resin per unit of glass, a hotter exothermic cure, and more shrinkage stress locked into the part on the day it was pulled. Thermal cycling then adds strain to a section that already started life under tension. That is why two coaches stored side by side craze at the same corners in the same order. Two local details make it worse. Lot sprinklers leave mineral deposits that etch the oxidized surface, and dust holds moisture against the panel overnight. Then the coach finally gets towed, the frame flexes on the freeway, and the crazing that had been internal opens up over one trip. ## The cheap repair against the expensive one **Caught at the dull band.** Paint correction and polishing runs $500 to $2,000 across 4 to 18 hours. The oxidized layer is compounded back to sound pigment, then sealed. Ceramic coating at $800 to $3,500 is the honest follow up for a coach that goes straight back into open storage. This tier lands in the light cosmetic window of 2 to 5 business days. **Caught at visible crazing.** Gel coat restoration runs $750 to $6,500 across 5 to 30 hours. The crazed field is sanded back below the depth of the cracks, tinted gel coat is re-shot, then cut and polished to match the surrounding gloss. Where the crazing covers a whole cap, fiberglass restoration and refinishing at $900 to $9,500 is the accurate line item instead. **Caught at an open crack.** Crack, hole and impact repair starts at $750 and runs into five figures, because the cracked laminate is ground out, rebuilt with glass, and then refinished. If water reached the core, delamination repair at $1,500 to $20,000 plus is the band that applies. Same corner, three prices, eighteen months apart. ## Ordering tinted gel coat to a color that may no longer exist Gel coat is not a shelf item in your coach's color. It is tinted to a formula, and the formula comes from the build sheet, a color code on the compartment placard, or a sample coupon we cut from a hidden area and hand to the supplier. Getting that right before anything is sanded is the difference between an invisible repair and a corner that reads as a repair from across a parking lot. A standard white or off white tint typically lands inside 5 to 10 business days. A metallic, a two tone, or a discontinued factory tint goes out to 2 to 4 weeks, and older coaches from manufacturers that have since closed are the hard cases because no formula survives. Those get matched instrumentally and then hand adjusted, which adds lab time before spray time. One trap specific to the clear layer. If the graphics sit under clear on your coach, the crazed area cannot be spot refinished without lifting the decal, so decal and graphics replacement at $500 to $5,500 rides along with the gel coat work. We check that during evaluation, because finding it later is what turns a quoted calendar into a moving one. ## Will a carrier pay for crazing? On its own, almost never, and knowing that in advance saves a pointless phone call. Crazing from UV and thermal cycling is wear, carriers exclude wear, and the exclusion is defensible on the policy language every time. What does get paid is impact. A rock off the SR-60 pavement, a ladder dropped against a cap, a corner backed into a post. Impact crazing looks different and photographs differently: the cracks radiate outward from a single point in a rough star rather than running parallel along a radius. Dated photographs and a clear picture of what struck the panel are what carry that claim. The middle case is consequential damage. If a covered impact opened the radius and water worked into the laminate over the following weeks, the delamination belongs in the original scope, written at the time of the estimate. Added later as a supplement it gets argued. Written up front it usually does not. ## Three checks to run before you cover the coach again Walk every radius on the vehicle at a low angle with the sun behind you: both front cap corners, both rear cap corners, the roof to sidewall transition, and the wheel well radius, which owners skip and which sees road heat from below. Note every band that looks matte while the panel next to it looks glossy. Run a fingernail across anything you can see. Nothing catching means you are in polishing territory today. Something catching means the laminate is open and the clock has already started. Photograph both cases with the date on, because that record is what separates a wear conversation from an impact conversation later. We are 18.4 miles from Hacienda Heights, 24 to 38 minutes via SR-60 west to Fullerton Road, and all of this work happens in the bay at the Yorba Linda facility. Call (949) 799-3387 with your coach length and the color code off the placard and we will tell you the gel coat lead time before you commit to a date. The evaluation is priced and credited to an authorized repair. --- Source: https://ocrv.club/blog/gel-coat-clear-layer-cracks-at-the-corner-radius-after-outdoor-storage-in-la-county OCRV Center, 23281 La Palma Ave, Yorba Linda, CA 92887 Phone (949) 799-3387. Email info@ocrvcenter.com. Serving Hacienda Heights and the surrounding area. 18.4 miles, 24 to 38 minutes via SR-60 west to Fullerton Rd, then south to La Palma Ave. In shop work only. All estimates are priced and credited against an authorized repair.