In Hornslet, Mekoprint has a large painting facility, which use industrial wet coating. The first process is a degreasing which also leaves an iron phosphating. The workpiece is then electrostatically painted, providing a better utilisation of the paint.
Mekoprint has the option to paint with robots and manually, depending on the volume.
Wet coating can usually be delivered in all known RAL and NCS colours.
Colours like red, yellow and orange do not have the best covering power and require a primer to avoid them taking on a different shade, e.g. yellow will often appear greenish. Workpieces that need to be primed first need to pass through the paint facility twice. Depending on the paint specification chosen, this may involve a doubling of the price of the surface treatment.
Mekoprint’s painting plant in Hornslet can use the following suspension area:
The painting plant can handle 7–10 per trolleys per hour. Delivery time for wet coating is approximately 10 days.
To the extent possible, workpieces must be equipped with suspension holes as all workpieces are suspended manually. Ø8 is usually sufficient.
In situations where this is not possible, the workpieces can be hung in a U bracket. However, hanging and taking down workpieces takes much longer if pressure clamps must be used. Workpieces suspended with U brackets will have a spot of approximately 6 mm which will not be painted.
All workpieces to be painted are first run through the phosphating plant that washes the workpieces and then rinses them with water.
All workpieces in which water might be collected shall be fitted with drainage holes. This also applies to workpieces with cavities.
If these holes are not present, a member of staff must be used to blow the water from the workpieces.
Many workpieces are laser cut, and the problem can often be avoided by having a few holes punched. This is a very cheap and effective solution.
Some surfaces are difficult to paint because the paint gun cannot reach them. For other surfaces, the painting process itself is what makes it difficult to cover the surfaces.
The paint is distributed with compressed air and there is an electrostatic charge between the workpiece and the paint in order to obtain better utilisation of the paint (some paint disappears past the workpiece and cannot be reused).
In narrow areas, e.g. in a box with tall sides, a pedestal, etc., the paint will be drawn towards the edges due to the electrostatic effect. Furthermore, the compressed air will shoot the paint back. This is comparable to trying to paint the bottom of a small bucket with a spray can.
Therefore, the bottom and the sides closest to the bottom do not get much in terms of layer thickness.
