Depending on the condition of the old paint, the type of new paint being used and the repairs that were done, sometimes a sealer must be used and sometimes a sealer should be used. Check with an automotive paint shop to be sure you match up the primer-sealer or sealer correctly with the paint you intend to use. The type of sealer to use depends on the paint to be applied. They can be used to prime bare metal and as a sealer under any enamel paint job. Primer-sealers are generally enamel based. Sealers are usually lacquer based, so they’re easy to apply and dry very fast. Sealers don’t have the same characteristics as primers – they’re applied over a primer or sanded paint coat to improve adhesion between the old paint and the new paint, provide a uniform colour background and ‘hold out’ for the new paint and to form a solvent barrier to help prevent sand scratch swelling and ‘show through’. Primer-sealers do the same job as primers, but they also seal better over a sanded old paint coat to provide uniform colour ‘hold out’ when the new paint is applied. Other common undercoat products that may be confused with primers are sealers or primer-sealers (some sealers prime as well as seal and are known as ‘primer-sealers’, while others only seal).
![primer paint primer paint](https://cdn.shopify.com/s/files/1/2196/8707/products/11676072_77c8ae9e-2b38-4973-9c26-3a67b9102dfd_1280x1280.jpg)
Etch primers are the only primers suitable for use directly on galvanised panels. Generally, etch primers do not require sanding, and 1K primer (high-build or otherwise) is usually spayed over the top before preparing the panel to receive the colour coat. Some paint manufacturers also produce etch primer ‘ready-to-spray’ in an aerosol can for repairs to small areas. The acid etches the bare metal, allowing the primer to adhere strongly to the panel, and providing excellent corrosion resistance. Etch primers are usually two-component products, which contain an acid activator. Etch primers are normally used on bare metal, but most types are equally effective on other materials such as plastic and fibreglass (check the manufacturer’s recommendations as to suitability for non-metallic surfaces).Įtch primers can also be used on galvanised metal or on top of existing primer to cover any minor damage in the protective galvanising coating. Etch primers contain an acid which etches bare metal, ensuring that there is a very strong bond between the primer and the panel surface. The purpose of etch primers is to replicate the cataphoretic dip priming process used by vehicle manufacturers to protect panels against corrosion. ‘High-build’ primer is not necessarily applied to give a thick ‘high-build’ layer, and can be sprayed to give a thin layer purely to provide a key fo colour coat. High-build primer can be mixed with thinners in various ratios to provide coatings of various thicknesses. The term ‘high-build’ is used by most paint manufacturers to refer to the primer used to prepare a surface for application of colour coat.
#Primer paint Activator#
High-build primers are usually 2-pack products which are mixed from 3 elements (primer, activator and thinner).
![primer paint primer paint](https://i5.walmartimages.com/asr/4f509ad0-84cd-4e9b-b3ac-5e9238d978a7_1.5457cd4c07b8a2be6b7b99c1a012a6c4.jpeg)
minor scratches and sanding marks) in the finish underneath. To provide a relatively thick coating which will fill any small imperfections (eg.High-build primer has three main functions: This type of primer is normally available as ‘high-build’ primer.
![primer paint primer paint](https://i5.walmartimages.com/asr/deff52db-6d19-42f6-b891-17e3d9706cb8_1.59390ef733aea7b18bf3b8c2fd21c87f.jpeg)
![primer paint primer paint](https://s7d2.scene7.com/is/image/homedepotcanada/p_1000450606.jpg)
The two main types of primers are: Primer lacquer (also known as 1K or 1-pack, or just Primer) and Etch primer.