Not far from the Böker factory headquarters in Solingen lies Burg Castle. This medieval fortress is the landmark of the Bergisches Land region and was the ancestral seat of the Counts of Berg, who gave our region its name. It is also one of the largest castles in western Germany and the largest reconstructed castle complex in North Rhine-Westphalia. Today, Burg Castle is used for a variety of cultural purposes, including as a museum, event venue, and memorial site.
RESCUE
The wood used for the handles of these special edition models comes from historic oak beams in the keep, the 32-meter-high main tower of Burg Castle. These oak beams were uncovered and replaced as part of the castle's renovation and energy-efficient modernization, which cost over €30 million. Thanks to our close relationship with the Burg Castle Building Association (Burg ad Wupper e.V.), we were able to obtain a small quantity of wood from these over 100-year-old oak beams. These new, limited-edition models are a tribute to our local history, to which we owe our craftsmanship.
PUNCHING / LASER CUTTING
The precise blade contour is achieved by laser cutting from the exceptionally durable O1 carbon steel. Due to its superior properties and excellent edge retention, this blade material is ideally suited for high-quality pocket knives. The brass liners (alder), brass spacers, and backsprings are traditionally stamped using in-house stamping tools and machines. The two to four nickel silver bolsters (depending on the model), as well as the small emblems and the nail nick on the blades, are meticulously stamped. Each blade is also marked with the "Böker Solingen Germany" hallmark. The four bolsters are then stamped from the blank, subsequently sawn apart, and deburred.
HARDENING
Before grinding, the blades are hardened to a final hardness of 60 to 61 HRC in the hardening shop. The carbon steel blades are held at a hardening temperature of approximately 870 °C for several minutes before being quenched in an oil bath. To prevent the very brittle blades from breaking during everyday use, they are tempered at approximately 150 °C to achieve the target hardness of 60 to 61 HRC .
GRINDING SHOP
In the grinding shop, the bevel, the long bevel from the spine to the cutting edge, is applied. For this, the already hardened blade blanks are individually placed by hand onto the blade-specific fixture. Particular care must be taken to cool the workpieces, as the blades could warp or even lose some of their hardness due to heat input.
HAND PLEATED
Sitting at the grinding wheel, each sharpened blade and spine is individually inspected and, if necessary, reworked in the hand-polishing workshop to ensure the mechanics of the finished knife are always reliable. Etching: The knives in this series unmistakably feature a very special blade finish. This not only serves as a visual highlight but also protects the non-stainless steel blade from harmful environmental influences. Each blade is dipped by hand into an acid solution.
DRUMS / SLIDING LOOPS
After the dark etching is applied, a uniform micro-scratch structure is created using a vibratory finishing process. For this, the blades are "washed" in a drum along with various stones; the rubbing and falling of the stones creates the desired effect, resulting in increased resistance to scratches and wear.
TRAY DEPARTMENT
In the bowl-making department, the next step involves the production of the historical bowls. The massive oak logs are truly unique, shaped by hand in bygone eras. Due to their varying lengths and the countless holes and recesses created by mortise and tenon joints and wooden pegs, processing them requires considerable experience and dexterity to minimize waste of this limited material. First, the logs are cut into blocks on a table saw, which are then further processed into squared timbers. These squared timbers are then used on the table saw to create delicate wooden bowls approximately 3.5 mm thick. Finally, the rough contour of the wooden bowl is pre-milled using a hand-held milling/sanding machine.
PRE-ASSEMBLY
In the pre-assembly stage, the two wooden shells are riveted to a tang each. The nickel silver jaws are also fixed to the plate using spot welding. To ensure that the guide pins can hold all the components together later on, the corresponding holes are now drilled.
RIDERY / ASSEMBLY
In the knife-making workshop , the two handle scales, the blades, and all other components are assembled using nickel silver guide pins and then pressed together. Even though the knives are complete except for the black-lined tree-shaped shield, these limited-edition collector's items still bear little resemblance to a smooth, tactile object.
MATCHING
In the finishing department, the assembled components, with their protruding guide pins, sharp edges, and overhanging oak scales, are transformed into a highly polished gem that makes every collector's eyes light up. Before reaching this point, each pocket knife is refined to perfection on four sanding belts with varying grits and speeds, a polishing felt, and linen cloths.
DEDUCTION
The knife now matches the final product in shape and contour – however, the blade is not yet sharpened. The blades of the individual models are unfolded and honed by hand on a whetstone at a 30-degree angle.
FINAL INSPECTION
In final inspection, the Böker emblem is inserted into the prepared blind hole. Each individual knife is carefully cleaned on traditional wooden sorting boards and checked for flawless functionality. Even the smallest defects are rectified, ensuring that only immaculate products make it into the packaging. The long journey of the historic Schloss Burg series through our manufactory draws to a close as it makes its way to the main warehouse. From there, with the purchase of the knife, a new journey begins as a reliable companion to its proud owner. All models are strictly limited worldwide to 1133 pieces (the year the castle was completed).