Finnish furniture manufacturer Isku chose UPM Grada® thermo-formable birch plywood as the starting point for its new student chair series. The material had been well received, and its properties had a positive influence on both the design and the manufacturing process. The result was a versatile Iris chair range for learning environments.
According to Isku designer Petteri Häkkinen, the seat part of the previous student chair was made of two parts using traditional wet veneer pressing
"In addition to usability and ergonomics, the design was guided by the idea of a one-piece chair that could be hung from the backrest to the table top. Using UPM Grada, we can produce the seat part with a single press, which allows for a fast and efficient manufacturing process," says Häkkinen.
UPM Grada® speeds up and simplifies the manufacturing process for industrial furniture and creates new possibilities for design and styling. Isku uses UPM Grada's features to manufacture its versatile Iris chair family.
Machining capabilities bring new possibilities for design
UPM Grada is a thermoformable plywood sheet that replaces the traditional veneer pressing method. In the UPM Grada forming process, the sheet is heated to 95 degrees Celsius, where the adhesive film between the veneers softens and melts. The sheet is then shaped and cooled in a mould to 70 degrees Celsius, where the adhesive hardens, and the piece remains in the formed shape.
According to Mikko Porter, Vice President of Development and IT at Isku, UPM Grada plywood offers new possibilities for shaping, also from a machining perspective.
"The sheet can be machined before it is pressed, allowing it to bend into new shapes. In general, the possibilities for automation at different stages are increased and, at the same time, the manufacturing time is significantly reduced. The investment in the mould pays off in terms of more efficient production," says Porter.
Isku’s Iris chairs are produced in 16 different models, with variations in surface materials, legs and other components.
In addition to high quality, the origin of the raw material and safety are important
An efficient production process, automation and design possibilities are not the only reasons to use UPM Grada. In addition to the high quality, strength and reliability of the product, Isku also values the domestic, FSC® (FSC C009856) or PEFC (PEFC/02-31-112) certified origin of the wood raw material, smooth deliveries and short transport distances from the UPM Savonlinna plywood mill, Finland.
"I appreciate the fact that the glue used in the plywood does not contain formaldehyde or other compounds that are harmful to health, which is both safe to use and safe to work with," adds Häkkinen, who uses the Iris Chair at work and at home.
"We have made the interesting observation that the surface of UPM Grada does not have the same slight waviness as parts made by the wet pressing method. The difference is only noticeable by side-by-side comparison, but it is there," Porter points out.