Bondo is a body filler generally used in the marine, household and automotive repairs. It is generally made up of a resin which has been mixed with a hardener or catalyst. In fact before the application of the bondo, the prevailing paint needs to be sanded off so that the bare metal becomes visible and then the filler needs to be applied. Just slapping the bondo will prevent it from sticking thereby result in just the waste of the bondo.
Powder coating generally does not go well with bondo and doing results in outgassing thereby giving rise to irregularities which will be visible even after the finish. Another reason why the two are not compatible is that bondo does not work well with high temperatures. Thus it tends to outgas during the curing process of the powder. A high temperature filler is thus recommended for the same so that it can be coated with powder to give it the required finish.
There are many different types of powders used to coat automobiles like:
- Epoxies: Durable with an excellent hardness, epoxies are the most widely used powders because of their excellent chemical and corrosion resistive powers. They stick very well to metals, are easy to use and have quite a range of curing schedules.
- Polyesters: They are very economical and thus very commonly and popularly used. They also offer a very good mechanical resistance thereby ensuring greater flexibility and are resistant to impacts and chemicals too.
- Super durable polyesters: They are polyesters with superior durability and higher resistance to the effects of humidity and corrosion.
- Epoxy-polyester hybrids: Combining the strengths of both the epoxies and the polyesters, hybrids are made so as to make the powder coating resistant to the effects of the weather. .
- Fluoropolymers: Characterised with phenomenal resistance to the effects of the weather, this type of powder also enables a high-class retention of both the gloss and the colour.
- Urethanes: They are chemically the same as polyesters but need different agents for curing. They also enable great exterior durability and are resistant to chemicals and corrosion but they are quite expensive when compared to the other types of powders.
The choice of the powder type depends on the product it is being used on and the need for the same. Thus the selection should be made with care.