Outgrowing the stairs

"We are future-proofing the company for the next generation." The medium-sized family business ETS Treppenbau und Schreinerei GmbH currently employs 26 people at its Dingdorf site in Rhineland-Palatinate. ETS is one of the enviable craft businesses that do not have to worry about company succession. In addition to the managing directors Albert and Klaus-Peter Ernzer, the three sons are already working in their parents' business - two of them, Jonas and Lukas Ernzer, already have their master craftsman's certificate "in the bag". The company specialises in the construction of wooden staircases, primarily for private customers, prefabricated house builders and joineries.

Initial thoughts on automation

"Stairs that inspire" is the motto of this long-established company. Their strength lies in customised staircases. The Ernzers are known and recommended for this in the region. But they are also feeling the effects of the shortage of skilled labour. "You have to find good industrial finishers first," says Alfred Ernzer. "That's why we started thinking about automating the processing of surfaces," adds Klaus-Peter Ernzer. For the Ernzers, increasing quality and saving time played an overriding role in the decision-making process. "Our customers increasingly want the surfaces of their stair treads to match the colour of the interior, especially the existing flooring. For this purpose, coloured stains or RAL colours are used as water-based UV coats, which we were previously only able to paint on the manual spray stand," reports Alfred Ernzer. The company's existing roll coating lines could only be used to apply clear coat. "Here, too, we had to do additional manual work to coat the edges," says Ernzer, describing the effort involved, which, to everyone's delight, is now a thing of the past. With the new coating system from Venjakob, everything can be coated, stained and dried in equal measure. "The entire coating system - from the spraying machine with three coat supply lines to the UV drying channel - is designed for the use of the desired water-based UV coatings and water-based stains and fulfils 100% of the EU environmental guidelines. In terms of time savings, Alfred Ernzer says: "We could now easily double the number of stair treads we can industrial finish."

First major order for chipboard has been received

But the vision is a different one. The new Venjakob coating lines, which are precisely tailored to Ernzer's needs, are to be utilised beyond its own capacity. "We want to accept more external painting orders for furniture construction," says Klaus-Peter Ernzer. The first major order has already been received: 5000 square metres of chipboard for interior fittings are to be painted. The system, which allows quick colour changes and has short drying times, is predestined for this. Ernzer is also impressed with the surface quality. "The uv curing in industrial coating, which can now also be used for coloured surfaces, makes the coat much more resistant and scratch-resistant."

System suitable for new hall construction

In future, the surface treatment process was to take place separately in its own hall. A new hall with an area of approx. 500 square metres was planned for this purpose. The ceiling height was low, as the hall was built directly onto the existing workshop at the same height. The coating line was to be designed to save space accordingly. The entire Venjakob system was built in a U-shape with rake angle transfer. Workpieces can be processed with the following shows in length, width and height: minimum 300 mm x 100 mm x 10 mm, maximum 5300 x 1300 x 100 mm.

We could easily double the number of stair treads now.
Alfred Ernzer

15 minutes for a complete cycle

the system is set up as follows: The workpieces are manually placed on the belt conveyor. Length markings are applied to the workpieces to simplify the process. Firstly, the workpieces are automatically preheated using an IR preheating module to remove dust. They are then conveyed to the Ven Spray Smart spraying machine. This is equipped with one paint supply line each for UV clear lacquer, UV colour lacquer and stain. Industrial finishing is carried out using four spray guns, which coat the surfaces and edges in equal measure. After coating, the workpieces are conveyed via a temperature-resistant belt conveyor through a covered vapour zone into the water-heated drying channel. This consists of two nozzle drying channels, which are mounted on an angled transfer system for transferring the batches. The workpieces coated with clear or coloured lacquer are cured in the subsequent UV drying channel. "The aim was for the workpieces to come out of the system dry after the base coat with colour or clear lacquer so that the intermediate lacquer sanding and then the top coat can be applied," explains Christian Schulze, the sales engineer at Venjakob who looks after the customer ETS. The time required for an industrial finishing cycle, from placing the workpieces on the machine to removing them, is around fifteen minutes.

Expertise and a good reputation are crucial

The system is easily controlled via a central control unit, which is used to call up coating recipes that have already been stored. "All important parameters, such as drying times, are stored in the recipe management system. We carefully coordinated these parameters with the customer and the paint manufacturer," says Christian Schulze.

Ernzer agrees that the investment has paid off. "Yes, there were more favourable offers. But the decisive factor for us was the expertise of the Venjakob employees and their good reputation. The system was planned and realised perfectly in line with our needs. The price-performance ratio is right for such a system," confirms Alfred Ernzer.