How to ensure a good result with 1K primers

AVOID ERRORS WHEN USING 1K PRIMERS

Incorrect use of 1K primers, typically in spray application, will show in the area being repaired. Unfortunately, we sometimes see problems with blisters in the topcoat. The reason for this is often the use – or abuse – of 1K primers. 

When should I use 1K and 2K?

The argument for using 1K primers is often that single-component primers are faster than 2-component versions. This is correct, but only when the product is used for small areas and sandings with a maximum diameter of 2-3 cm – and then only when the paint has a reasonable layer thickness. If you choose to use 1K primer on areas that are larger than recommended, you run a significant risk.

Risks in use of 1K primers

Improper use of 1K primer can result in small, blister-like bubbles in the paint, for the following reasons:

• Undesirable weather conditions
• Insufficient drying time
• Layers are too thin
• Layers are too thick
• “Wet on wet” application
• Dry application in an attempt to reduce drying time. That is, the primer is too dry and resembles a thin layer of dust, without proper adhesion to the underlying primer coat.

Eksempler på tørretider for 1K primere

It is recommended that all 1K primers for applications of less than 50 microns should only be used in a 3-layer system. This means that 2K fillers must be applied, and then basecoat and clearcoat; this also applies for spray painting. 

For layer thicknesses of +50 microns, solvent-based basecoat and 2K topcoat can be applied directly.

Nothing can be applied until the product is dry. At 20 ° C, the drying time is a minimum of 65 minutes, and at 60 ° C the drying time is 35 minutes + cooling before paint can be applied.

* PS1600A is only for very small abrasions on edges, corners etc. 

EXAMPLES OF DRYING TIMES FOR 2K PRIMERS AND UV PRODUCTS

As the charts show, using 1K primers will not save time compared to using 2K products.