For decades, Bondo has been the go-to automotive body filler. It does a great job of filling holes and dents. Over the years, different varieties of Bondo have been introduced into the market, and Bondo hair and glass are good examples.
From a general point of view, these two may seem almost the same, but there are key differences that distinguish one from the other.
If you want to go Bondo shopping and don’t know whether to choose Bondo hair or Bondo glass, here is an overview of both.
What is Bondo Hair?
Bondo hair was created for the toughest repairs. It is known in full as a long-strand reinforced fiberglass filler. The reason why it’s a great choice for heavy-duty repairs is the presence of long hair fiberglass strands.
These long strands outperform the regular-sized strands found in Bondo glass. This type of filler can be used to fill dents that are up to an inch deep or wide. If you are accustomed to regular Bondo, you know that it can only fill a hole a quarter-inch deep.
Besides car metal, Bondo hair can be used on fiberglass and wood. It’s, therefore, an excellent addition to your garage since it serves versatile purposes.
Bondo hair is made using a fast-drying formula. Therefore, besides being two times stronger than a regular Bondo, you will enjoy quick results.
This type of Bondo is meant for challenging projects such as vehicle restorations and filling huge rust holes. The long strands of fiberglass found in Bondo hair measure up to an inch long, and they are quite durable.
With Bondo hair, you don’t need the help of backing mats, cloths, or strips. When it cures, it can sit in a hole on its own.
Since it’s a bit thicker than regular Bondo, it may require more elbow grease when sanding. However, its formula allows you to sand the Bondo hair in a much shorter duration, ensuring you finish your projects on time.
If you are using Bondo hair, remember to get a hardener. A hardener plays a critical role in ensuring the Bondo cures into a durable filler.
It’s also important to note that Bondo hair is compatible with a wide range of primers, paints, and fillers. But you should always confirm before starting any project.
If you read reviews of Bondo hair, you will realize that this is a truly remarkable product. The long strands make it ideal for the most complicated repairs.
If your vehicle has huge rust holes, Bondo hair is the best product for performing such repairs. Instead of using fiber cloth and epoxy, Bondo hair can fill your rust holes and remain put throughout your car’s lifetime.
It’s stronger and better. However, don’t make a huge mess with this type of Bondo because it doesn’t come off easily.
It may require the intervention of a strong solvent such as brake cleaner. There have been complaints that it hardens quickly. So, when using Bondo hair, make sure that you act quickly.
What is Bondo Glass?
This is the miniature version of Bondo hair. It also features fiberglass strands, but they are much shorter and smaller. Bondo glass is ideal for light-duty repair jobs.
If you have small rust holes and want to use a quality and durable filler, Bondo Glass is a perfect choice. Among DIY detailers, Bondo glass is a favorite option. It can fill holes that are about half an inch in diameter.
Even though it isn’t as strong as Bondo hair, Bondo glass works perfectly without backing strips. Bondo glass comprises short strands of fiberglass that are interlocked together.
It is way better than regular Bondo. And if you want lasting results, this is what you should use on your car.
Similar to Bondo hair, Bondo glass requires a hardener. Make sure that you get one when shopping. Its formula is easier to mix and apply. It’s also easily sandable.
A word of caution; once you add the hardener, you have around twenty minutes before it dries up. Make sure that you work fast.
As a fiberglass filler, Bondo glass is waterproof. You, therefore, need not worry about car washes and weakening your filler.
It is compatible with different types of paints, primers, and fillers. Before we move on to the differences, you should know that Bondo glass can be used on shattered fiberglass body parts. It’s therefore versatile.
How Are They Different?
• Bondo Hair Can Fill Holes Measuring 1″, and Bondo Glass is Ideal for Holes Measuring ½”
The biggest difference between these two is the fiberglass strand size. There is a reason why Bondo hair is known as long-strand fiberglass filler.
That’s because it has strands that measure up to 1 inch long and can fill a rust hole measuring a similar diameter.
On the other hand, Bondo glass has smaller fiberglass strands, making it suitable for holes measuring around half an inch.
This difference determines when you should use either of these fillers. If the rust holes or dents on your car are bigger, go for Bondo hair. Bondo glass is a much better choice if they are of average size.
• Bondo Hair is for Heavy Duty Jobs, and Bondo Glass is for Light Duty Metal Restoration
The other difference that is also brought about by the varying strand size is what jobs each can be used for. Bondo hair is formulated for tough repair jobs such as full vehicle restoration.
The long strands stand a better chance of fixing heavy dents and bigger rust holes. On the other hand, Bondo Glass is perfect for every day repairs.
If you have just spotted a rust hole under your car door, you can use Bondo Glass as a quick and durable fix.
How Are They Similar?
The similarities between Bondo hair and Bondo glass are many because these two products feature almost the same formula. Other than the difference in strand length, these two can be used interchangeably.
Both;
• Have Fiberglass Strands
Both Bondo hair and Bondo glass are made using fiberglass. Even though there is a difference in strand size between these two products, the formula, and list of ingredients are the same.
While we are still on fiberglass, you should know that this material is stronger and more durable than ordinary putty resin. If you want lasting results, opt for fiberglass automotive fillers.
• Are Waterproof
Since they are all made using fiberglass, these two types of Bondo are waterproof. Whether you go with Bondo hair or Bondo glass, no matter how much water the repair is exposed to, it will hold up since it’s waterproof.
The main reason most Bondo repairs don’t last is the penetration of moisture. However, since there won’t be any moisture getting inside, your filler repairs should withstand the test of time.
• Require a Hardener
You can’t use either without a hardener. That’s just how fiberglass Bondo is designed to work. The hardener enables the Bondo to cure on dents or holes.
If you don’t add a hardener, there is a huge chance that the Bondo will fall off after a while. You will then have to start the repair from the beginning.
• Dry Quickly (Less than Twenty Minutes)
As long as you use a hardener, it should dry pretty quickly, whether you are applying Bondo hair or Bondo glass. Both often take around twenty minutes to harden. Make sure that you act quickly.
• Compatible With Different Paints and Primers
You can use Bondo hair and Bondo glass with typically any paint or primer. But it’s advisable to research whether they are compatible. This will ensure you avoid surprises in the future.
• Have Versatile Uses
You can use Bondo hair and Bondo glass on fiberglass, wood, and metal. Considering how versatile they are, it’s important to have both on your garage shelves.
• Don’t Require Backing Strips or Cloths
These fiberglass fillers can fix rust holes on their own. That’s how strong they are. You don’t have to use a backing strip or cloth.
What’s Better about Bondo Hair?
The main benefit of Bondo hair over Bondo glass is the long strands of fiberglass. These long strands ensure that the Bondo hair can tackle the toughest vehicle restoration and repair jobs.
Bondo hair should penetrate the crevices and dry into a strong and durable filler if you have massive rust holes.
What’s Better about Bondo Glass?
Bondo glass works best if you want a quality filler that is easy to apply. Bondo glass features shorter strands that are interlocked to repair metal and other materials such as wood and fiberglass.
Compared to Bondo hair, it’s much easier to mix and apply. That is the biggest advantage.
Who Should Get Bondo Hair and Why?
Bondo hair should be used by expert detailers handling a complex vehicle restoration job. If a client brings in a car with big dents or huge rust holes, you can bring in the long-strand fiberglass filler for the best results.
Who Should Get Bondo Glass and Why?
If you are a car owner interested in fixing a tiny rust spot and you want a quality finish, go for Bondo Glass. The fiberglass in Bondo glass will create a durable finish that will withstand bad weather. It is strong, durable, and doesn’t require backing strips or cloth.