Composite chef’s knife a chef d’oeuvre
A while back I blogged about a luxurious version of a champagne flute, via carbon fiber and gold. The designer, Ragnar Friberg, is at it again, this time with a composite take on the chef’s knife.
#layup #spreadtow #adhesives
Beautiful chef’s knives with composite handles are designed and made by Sweden’s Ragnar Friberg
A while back (https://www.compositesworld.com/blog/post/not-your-average-carbon-fiber-part) I blogged about a luxurious version of a champagne flute, via carbon fiber and gold. The designer, Ragnar Friberg, is at it again, this time with a composite take on the chef’s knife.
Friberg tells me that the knife blade is hand-forged steel from Sakai (Sakai, Japan). The other elements include “Samurai” spread-tow carbon fabric [61 gsm] from Sakai Ovex (Fukui-City, Japan) made with Toho Tenax (Tokyo, Japan) HTS40 12k carbon fiber, and…moose skin. He explains “I laminate the composite layers, alternating carbon fiber fabric and moose skin, using epoxy supplied by Nils Malmgren [Ytterby, Sweden]. The layers are placed over a peel ply on a vacuum table to help hold the layers flat, because it is tough to get the moose skin totally soaked with the epoxy.” The layup goes into an aluminum mold, under a caul plate (160 by 80 by 7 mm in size), and is cured for 16 hours at 60°C. He points out that the outermost layer of the handle, made of moose skin with decorative inserts, is laminated separately to avoid any damage.
Friberg also laminates multiple layers of the carbon fabric alone, and cures it to form a solid carbon billet 2.5 mm thick (thickness can vary depending on the exact steel blade used). He continues, “The shaft end of the blade is a bit shorter than the overall knife handle, so I fill in that area with the solid carbon.” Using a pattern, he then cuts from the cured carbon/skin laminate two segments, which form the two sides of the handle; these are further shaped by sanding. Using a fixture, the steel blade is placed between the two shaped handles and the solid carbon piece, together with the outermost decorative skin layer, forming a sandwich that is adhesively bonded together with Nils Malmgren NM 650 epoxy adhesive.
“The rest is all finishing work, with several coats of clear coat and lots of polishing to a high gloss, which sounds simple but it takes a lot of time,” says Friberg. Handles and blades can be customized, to fit a customer’s hand precisely. And the price? Contact Friberg if interested: firstname.lastname@example.org, or email@example.com.
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