Using Sonneborn & Rieck’s latest UV finishing systems is contributing to both product quality and production flexibility at Timbmet Door Solutions Ltd (TDSL).
At the latter’s new 25,000ft2 factory at Mansfield, the advanced finishing line, including a state-of-the-art roller coater and UV curing plant from the Cefla group, is continuously producing a wide variety of bespoke doors, in either open grain or closed pore full finishes, at throughput rates from 12-25m/min. That’s about one door every four minutes.
The Sonneborn & Rieck high solids, acrylic finish used by the company is designed to equal products applied by curtain and spray coating in both smoothness and depth.
In fact, the company says the product can be used to give a controlled thickness of coating from a thin film to exceptionally high build. The end result, it claims, is highly durable and the gloss level can be easily varied on the line to the required surface specification.
Sonneborn & Rieck says that its finishes are made to fit the individual customer’s requirements and to be compatible with any form of application equipment.
At its applications centre in Hainault, the company recently installed a full-scale, production version of the advanced Cefla roller coating system now being used at TDSL. This enables it to demonstrate its finishes in factory conditions, and relate them directly to the factory environment.
The use of one finish, for varying levels of open grain or closed pore, also means the user’s downtime is kept to an absolute minimum and, according to Sonneborn & Rieck, there is virtually no waste.
Sorbini plant
The roller coating and UV curing plant installed at TDSL comes from Cefla subsidiary Sorbini. To ensure it obtained exactly the kind of finishing quality, speed and flexibility it required for its doors, TDSL had exhaustive tests carried out at Cefla’s headquarters, using finishes from a variety of companies before opting for Sonneborn & Rieck.
TDSL is using a high build sealer and a high viscosity UV basecoat, plus UV-cured, 100% solids acrylic finishes that can be used either for open grain coating or, via Cefla’s Opti-Roller, a top coating of up to 35g/m2 to provide a full, so-called ‘Italian’ finish. Gloss levels can be easily varied by between 15-20%.
The final result, says TDSL, is the kind of lustrous sheen that is already popular in the rest of Europe and is expected to provide an increasingly attractive alternative in the UK to the open grain finish conventionally favoured for doors in domestic and commercial interior design.
According to Jim Gibson, TDSL’s production director, the flexibility of the finishing system enables the company to produce a vast array of clear finished doors. And the ease with which the set-up enables TDSL to switch swiftly between different types of coating is proving especially useful for bespoke products.
The bulk of the company’s doors are lipped, veneered designs, mainly in beech, walnut, maple, oak, plus any other customer-specified veneers. In addition, TDSL produces solid timber doors, including acoustic, lead-lined, and laminate-faced products in fire ratings from FD30 to FD120. Mostly products are supplied as doorsets – with frames and lippings being sprayed separately using a Sonneborn & Rieck water-based, air drying finish.
Production line
The new finishing line begins with an SCM wide-belt sander for fine sanding and denibbing, followed by a two-head Sorbini SP1 Smartcoater, a combined roller coating and filling machine which has a smooth rubber application roller followed by a chromed steel one. The first roller applies a basecoat and the second Sonneborn & Rieck’s high viscosity filler which closes the veneer pores.
Next, a single UV lamp provides partial curing of the basecoat or filler coat in preparation for a further coating at the next two-head Sorbini roller coater and full, final UV curing. The advantage of this gel-coat system is a superior UV-cured basecoat, requiring only limited denibbing.
The second Sorbini two-head roller coater in the line comprises a smooth rubber application roller, required for open grain basecoats and topcoats, and a laser-grooved rubber roller to provide the additional build-up necessary for closed pore finishing with the Sonneborn & Rieck topcoat.
“The kind of finish being achieved is as good as that provided by a curtain coater,” said Steve Toon, sales manager at Cefla UK. “And the special formulation of both basecoats and topcoats means there is no likelihood of the orange-peeling that can sometimes disfigure thick coatings.”
Sonneborn & Rieck says that its UV-cured acrylic finishes also result in a clear coating with none of the ‘milkiness’ once associated with this type of product.
After the second roller coater is a two-lamp, full UV-curing station, followed by offloading and stacking and where necessary, a return to the front of the line for the next finishing stage.
