Fiberglass Filler - What is it and Why Use it on Auto Body Repairs?

What Is Fiberglass?apply a thin layer of fiberglass filler over any
Raw fiberglass come in a soft fabric like material.welding that is performed. Body filler absorbs
When saturated with liquid resin and harder, itmoister, which will leads to corrosion and rust. By
becomes hard and very strong. There are notusing the fiberglass, we eliminate the moister
too many fiberglass auto parts on modern dayabsorption problem. Since our main purpose is to
cars, as they have all started using otherseal the welded area, the short hair fiberglass is
composites like SMC and Carbon Fiber. However,sufficient for the application.
fiberglass was on early model corvettes, truckWhat Can Fiberglass Filler Be Used On
hoods, and many other parts. There are stillThis filler can be used over bare metal or
aftermarket parts that are manufactured fromfiberglass.
fiberglass and it still used for boats and jet skis.Finishing The Repair
The Difference Between Fiberglass and FiberglassAs I mentioned, fiberglass does not sand well.
FillerThat is why I recommend only applying a small
Fiberglass filler comes in a can and is mixed with aamount to the welded areas and rough sanding it.
cream hardener. It mixes a lot like regular bodyAfter this is done, you can apply body filler on the
filler, but it is thicker and a little harder to mix. Thetop of the fiberglass filler and finish the repair as
filler actually has fiberglass mixed in it. It comesyou normally would using body filler.
short hair and long hair. This is the length of theWarning
fiberglass that is mixed in the filler. Both provideYou should always wear proper protective
excellent waterproof properties as they do notequipment when sanding any filler. However,
absorb water. Both fiberglass fillers are strongerextreme caution should be taken when sanding
than regular body filler. The long hair filler providesfiberglass products. It not only itches and irritate
the most strength out of the two. However,your skin, but it is extremely unhealthy to
these fillers are very difficult to sand. The filler isbreathed the fiberglass. Be certain to wear an
also thick, which makes it hard to level andapproved dust respiration, gloves, eye protection,
smooth like regular body filler.and you may even want to wear a disposable
Why Use Fiberglass Filler If It's So Difficult Topaint suit. If some of the fiberglass does get on
Sandyour skin, take a cold shower. This will help keep
The reason we use fiberglass filler in auto bodyyour pores small and allow the fiberglass to wash
repair is not really the added strength, but for theoff.
waterproof properties. It is recommended to