Car Body Filler can quickly repair small dents and dings in automotive paint, fiberglass, or metal surfaces without cracking and shrinking over time. It dries quickly while remaining crack- and shrink-resistant.
Before applying filler, surfaces should be thoroughly cleaned of wax or grease build-up and debris. Plastic spreaders are best used when spreading fillers as metal ones may scratch or mark surfaces.
Surface Preparation
Body filler (commonly referred to as Bondo) is a polyester resin with a creamy hardener that’s designed to restore vehicle surfaces back to their original smooth state after damage. It can be applied in various ways for repair purposes ranging from minor dents and creases to smoothing out warped panels or reshaping body lines. Sanding, priming and feather edging techniques help ensure optimal results when it comes time to use body filler on damaged areas; using feather edging will create a seamless transition between repaired surfaces compared with original surfaces surrounding repaired.
Prior to applying any filler products, it is vitally important to first thoroughly clean and prep the surface by removing any loose paint or rust, followed by sanding to roughen up its surface for better adhesion. In addition, corrosion resistant primer should also be used as protection and provide a smooth foundation for repairs.
When applying body filler it is vital that the product instructions and maximum application amount are adhered to. Excessively mixing will produce dry, crumbly filler that cannot be sanded away easily and requires extra work to blend and smooth over the surface of a car. Inadequate mixing or working too quickly could result in improper curing conditions which will not adhere well and could flake off later on.
Once the filler has been mixed, it should be applied evenly across the prepared surface using a plastic spreading tool and firm pressure should be applied when spreading it out.
Body filler application should be done on a warm, dry day to allow the product to set faster. Furthermore, direct sun exposure could cause too-quick setting times that could crack and shrink the filler prematurely.
As soon as body filler begins to dry, it is critical that it be sanded with a block and P80-grit sandpaper starting sanding it using a guide coat applied prior to using a DA sander to reveal high and low spots and indicate when to stop sanding.
Application
Body filler can help repair small dents and dings on the body of your car. It can also be shaped to smooth over damaged areas by following proper steps for mixing and applying body filler for best results. To ensure a quality finish, follow all necessary instructions when mixing and applying body filler to achieve quality results.
First, clean the area where you plan to apply body filler. Clear away any dirt or grease, and lightly sand the area to roughen up its surface so the filler adheres better. Once this step has been completed, mixing body filler can begin.
There are three grades of body filler: standard, medium and premium grade. These consist of polyester resin mixed with hardener that can either be pre-mixed or separated for ease of application. Your choice will depend on the size and nature of the bodywork that needs doing.
Standard-grade filler is the least costly choice available and ideal for making quick repairs to metal and fibreglass surfaces, such as minor dent repairs. It dries quickly and sanding it down is straightforward – making this solution perfect for patching minor dent or damage repairs on metal and fibreglass. However, its lack of stain resistance prevents its use on galvanised steel surfaces.
Medium-grade body filler offers a higher quality finish and more durability than its standard-grade counterpart, making it easier to sand down while being better suited to larger bodywork as less putty/glaze layers may be needed. Unfortunately, its thicker consistency may make working with it challenging.
Premium-grade body filler is more costly, yet offers higher quality and stronger adhesion than medium-grade fillers. Furthermore, it is easier to sand than the latter type and more suitable for high-quality bodywork due to not needing as much putty or glazing layers – though extra care must be taken with its application as if applied incorrectly it can stain easily.
Once mixed, body filler must be spread over the repair area in a thin layer, known as a skim coat. This step is essential to achieving an attractive repair result. Take your time and do this carefully so that any filler does not settle onto existing paintwork or become visible through cracks in its application.
Drying Time
Body filler is a mixture of polyester resin and cream hardener that forms a putty-like substance for use on vehicle surfaces after minor damage, similar to spackle used to repair walls and ceilings; it must then be sanded to achieve a smooth finish before painting can occur. For best results, several thin coats should be applied, each time with fine-grit sandpaper being used between applications of body filler.
Today’s high-performance plastic body fillers make repairs simple and quick compared to earlier generations of heat-shrinking metal fillers or lead. Non-shrinking, they dry quickly into hard, durable material that can be primed and sanded later for same-day repairs.
Before selecting the appropriate body filler product for your individual needs, it’s also essential to know how long body filler needs to cure before being sanded and painted. The duration depends on various factors including thickness of application, temperature/humidity levels and your chosen surface preparation method. If unsure which body filler product or amount would best fit your project needs, professional body shops are available to provide guidance as to which product and amount should be purchased for optimal results.
Filler that is properly mixed should be ready for use within 10 minutes. If it thickens prior to this point, chances are it either contains too much hardener or wasn’t mixed well enough with its filler components. A uniform color signifies that both components were evenly combined.
Though it is technically possible to sand filler while it’s still in its “green” stage (solid, slightly rubbery), this will prove much more laborious and time consuming. Therefore, it is usually preferable to wait until the filler has hardened to the point that it no longer flexes before shaping it with successively finer grades of sandpaper while wearing both respirator and protective eyewear.
Final Coat
Body filler has developed an unfavorable image due to being mishandled by amateurs. A perfect example is when show cars or used car dealership lots have chunks of Bondo falling off them – this can only serve to misrepresent its true purpose as one of the greatest tools available to professional body shops and enthusiasts alike. But used correctly, body filler can become one of the greatest tools at your disposal!
Body fillers are designed to fill imperfections on repaired surfaces and act as the final step before painting is applied. While not designed as replacement metalwork repairs, they should still be considered an effective option before going ahead.
Before beginning work with any type of filler, it’s essential that you have all of the appropriate tools and supplies on hand. Start by cleaning off your work area of wax, grease or dust; use a hammer or dolly to straighten out as much of it as possible before moving on to applying your filler – investing extra time here will pay dividends when applying it and creating a smooth finish.
Once you’ve applied several thin layers of body filler, the next step will be sanding it back down and eliminating any imperfections. Please be sure to use protective PPE when handling filler; such as gloves, sweatshirt and goggles; as well as working in an airy space with proper ventilation.
There is a range of body fillers to choose from, ranging from affordable single-component polyester fillers to higher grades of resin that have specific applications and help achieve professional-looking finishes.
Selecting an appropriate filler depends on your level of detail in repairing, as well as cost and durability considerations. Inexpensive solutions may work better for minor dents and creases while premium grades offer exceptional stain-resistance.
After you’ve sanded down the surface, it is crucial that you apply a high-quality automotive primer. SYBON provides an extensive selection of automotive primers; be sure to consult an associate in order to select one best suited to your individual needs.