Before you begin to spray a fresh layer of paint, you will need to use a car body filler for filling defects panels. Auto body fillers are designed to bond with a range of automotive components and bare metal for repairing damage.
The best body filler is the 3M Bondo 261, which is designed specifically for automotive usage and cures in minutes ready for sanding.
Body filler is often referred to as “Bondo” and when used properly, it can make bodywork repairs straightforward. It is far less time consuming and expensive than replacing the entire body panel with a new part.
Table of Contents
- Best Body Filler
- Car Body Filler Buying Guide
Best Body Filler
|Auto Body Filler||Size||Mixing|
|3M Bondo 261||14 Ounces||Yes|
|Evercoat 156 Lite Weight||101 Ounces||Yes|
|Permatex 25909 Liquid Metal||3.5 Ounces||No|
|Dynatron 492 DynaLite||101 Ounces||Yes|
|Evercoat 421||30 Ounces||Yes|
Repairing a panel begins with the filling process and its important that you get it right. Once you have filled the damaged panel with a body filler, you can then apply a base coat and finish up with an automotive clear coat.
To ensure that you get the best results during the filling process, you may need some extra tools. We recommend that you have spatulas, spreaders and plenty of sand paper available when using a car body filler.
Below is a list of the best body filler for repairing damaged auto body panels in a matter of minutes without the need of replacement panels.
3M Bondo 261 Auto Body Filler
3M are a reputable brand in the automotive industry with most of their products being used by professionals. The popular Bondo 261 body filler that they produce is a two-part putty compound that cures quickly and doesn’t shrink.
The Bondo formula was initially developed in 1955 and is well known among collision repair professionals for a high quality finish.
Features of the 3M Bondo 261 include:
- Designed for automotive use
- Microsphere formula
- Pink color when mixed
- Easy to mix and spread
- Suitable for a range of surfaces
- Includes a cream hardener
- Cures in minutes
Overall, it is the best body filler for beginner or professional use with a reputable brand backing the formula. It will permanently fill damaged panels and can be used for a range of other applications too.
Evercoat 156 Car Body Filler
Evercote are a popular brand within the body filler industry with a range of products available. The 156 Lite Weight is their most rated formula that is available in large cans for tackling large damaged panels.
Features of the Evercote 156 Lite Weight include:
- Smooth spreading and easy sanding
- Superior adhesion
- Include blue cream hardener
- Suitable for filling depths of 1/4 inch
- Doesn’t clog up whilst sanding
- 101 ounce can
The Evercote body filler does come with a premium price tag but it is worth paying the extra for it. Features such as the vacuum processing during manufacturing and non-clogging formula make the application far easier.
Permatex 25909 Liquid Metal Body Filler
The Permatex Liquid Metal formula is designed for filling, bonding and repairing automotive metals. Unlike most of the alternatives, once fully dried, this body filler is able to be drilled without causing cracks to the rest of the filler.
Other features of the Permatex 25909 include:
- Suitable for galvanized metals
- Resistant to water, oil and gasoline
- Easy to use with no mixing required
- Suitable for metal, wood and concrete surfaces
- Metal tough bond
One drawback of this body filler is that it is only available in a 3.5 ounce tube, which can become expensive for larger repairs.
Overall, the Permatex 25909 Liquid Metal Filler is an excellent all-round body filler for automotive usage. It is the perfect solution for small repairs that require a durable finish to withstand tough conditions.
Dynatron 492 DynaLite Body Filler
The Dynalite formula by Dynatron is another body filler by 3M but using a different brand name. It is a 2 part polyester compound that easily mixes with the provided hardener. The brand claim that this filler is compatible with the majority of paint system and dries in just 20 minutes.
Other features of the Dynatron 492 DynaLite includes:
- Excellent adhesion with consistent quality
- Available in 0.8 gallon, 1 gallon or 1 quart cans
- Fast drying formula that sands easily
- Easy mixing with the hardener
- Professional grade finish
Overall, it is an excellent alternative to the other recommendations and offers great value for the money. The larger cans allow you to tackle multiple jobs without going through multiple small tubes.
Evercoat 421 Automotive Body Filler
Another auto body filler by Evercoat is the 421 formula, which is more expensive but include extra additives. For example, it uses Hattonite, which acts as a dry lubricant whilst sanding and this helps reduce clogging of the sandpaper.
Other examples of premium qualities include the ZNX-7, which provides superior adhesion to galvanized steel and aluminum.
Features of the Evercoat 421 Automotive Body Filler include:
- Stain resistant resin
- Low porosity finish to reduce shrinking
- Include blue cream hardener
- Suitable for damage up to 1/8 inch in depth
- Hardens within 20 minutes
- 30 ounce bottle
Although it is expensive compared to other body fillers, it certainly makes the process of filling in damaged panels far easier. If budget is not an issue, the Evercoat 421 formula will not disappoint.
Car Body Filler Buying Guide
Repairing damaged body panels with a car body filler can be less time consuming and much cheaper than a new replacement part. It is a polyester resin formula that includes a cream hardener with various filler grades to choose from.
Before attempting to fill damaged panels, you should always assess the damage. Although body filler can make a huge difference, it cannot be the solution for all types of damage.
To help you make an informed buying decision, we have produced the below guide regarding auto body fillers.
Different Types Available
There are a range of different fillers available that are suitable for certain defects. These are categorized into standard, medium and premium body fillers.
Standard body fillers are lightweight with a putty formula that spreads easily, which is great for beginners. They are perfect for small repair tasks such as rust spots or large chips in the paintwork.
Medium grade body fillers are fiberglass filled and are higher quality that are great for tackling tears, holes, cracks and damaged fiberglass panels.
Premium grade body fillers are mostly used by professionals that require the highest of quality. This comes with at an additional cost but they provide better adhesion, easier to sand and the highest stain resistance.
Choosing between the different types is highly dependent upon the size and type of repair that you are carrying out.
How to Repair a Panel
To ensure that you get the best possible results when filling in damage panels, follow the steps below to restore the paintwork.
- Use a dent puller for any dents and remove any surface rust.
- Mask up the damaged panel.
- Prepare the filler and mix if required.
- Begin to apply the filler with an applicator in even layers.
- Allow adequate time for it to completely dry.
- Begin the sanding process and ensure the surface is smooth.
- Mask up again for priming and painting.
- Apply a clear coat once the paint has dried.
- Assess the repaired panel for any defects.
- Apply a rubbing compound for showroom results.
When applying the filler (step 4), its advised that you use moderate pressure. This will ensure that any trapped air escapes and the filler reaches all the gaps.
Most body filler formulas will require mixing of the filler and a hardener, which will be stated upon the packaging. Failing to keep to the recommended portions can have a negative effect upon the formulation of the filler. For example, too much hardener can cause it to crack whilst too little will delay the drying and hardening process. The below image is an example of how much hardener (red putty) you should use with the filler.
We would also advise that you avoid using cardboard as a mixing board as it will absorb resins from the mixture. Instead, use a plastic mixing board designed for body filler. If you notice that it is hardening too quickly, you may want to invest into a filler thinner, which ensures the filler can be spread easily.
Before you begin sanding the filler, it is important that you allow it to fully dry out. Depending upon the type of filler you use, this may take between 10 to 30 minutes or a few hours. The thickness of the filler will play a big part in how long it takes to dry.
You can help decrease the drying time by increasing the temperature in the room or using a heater on a low setting.
As briefly mentioned above, it is recommended that you use a plastic mixing board and spreader. This will help you easily spread the body filler into the paintwork and only costs a small amount extra. Using random objects such as cardboard can make it difficult to achieve the best results.
Surfaces That Can Be Filled
Body filler is not only used within the automotive industry but also for woodworking, domestic and other applications. Certain fillers are not compatible with certain surfaces and this may be an issue when repairing vehicle panels.
Therefore, you will want to ensure that body filler you choose is suitable for the metal found on your car. Some of the fillers such as the Bondo 261 can be used on wood, steel, aluminum, fiberglass, wood and concrete.
If you are filing in a rust spot, you will want to ensure that all rust has been removed. We recommend that you use a wire brush to scrape loose debris and complete the removal with a rust prevention spray.
Repairing damaged panels with an auto body filler is far cheaper than a replacement panel. It is also far easier and less time consuming, so it makes sense to try it out. All of the recommendations are relatively affordable and allows you to get professional results with ease.
If it is your first time using a body filler, we recommend that you trial it on a spare panel. Preparation is key to achieving the best finish and if you fail to correctly apply the filler, it can make the paintwork look terrible.