A first coat of paint applied before applying the finishing colour, or topcoat. The undercoat is usually coarser than the topcoat, to give good adhesion to the substrate below and the paint being applied over the top. It also brings a model back to a single colour, which can be useful if parts have been mould ed separately and are slightly different in colour. It can be also advisable to use an undercoat if you think there may be excessive amounts of release agent on a model kit, although cleaning the plastic thoroughly with warm water and soap is always best. Undercoat s are most commonly grey, since grey is easy to hide with most topcoat colours.
Any coat applied to a surface after priming and before the finish coat. It is matt with a high content of pigment and extender and a colour approaching or helping that of the finish coat. They have many functions, increasing the thickness of the overall film, hiding the colour of the primer or the previous layer on the existing substrate, and they are generally tinted in a similar colour range as the topcoat. Varnish undercoats have less oil per unit of resin than varnish finishes.!-- google_ad_client = "pub-8039990704443990"; google_ad_width = 468; google_ad_height = 60; google_ad_format = "468x60_as"; google_ad_type = "text_image"; google_ad_channel ="6807473505"; google_color_border = "FFFFFF"; google_color_bg = "FFFFFF"; google_color_link = "0000FF"; google_color_text = "000000"; google_color_url = "FF3300";
An intermediate part of a coating system, generally applied over primer or previously painted surfaces, which has high obliterating power and ability to provide a more level surface for the topcoat. In protective coating and industrial applications it is often called a 'build coat'.