This 3D model uses readily available spare parts for rotary knife sharpeners (such as those from Horl) to cost-effectively build your own rotary knife sharpener.

• Plate1 – The rotary sharpener itself
• Plate2 – The rotating shaft
• Plate3 – Knife holder at 20° – the standard angle for knives in Europe (solid construction)
• Plate4 – Knife holder at 10° – extra sharp but more delicate
• Plate5 – Knife holder at 15° – the compromise between 20° and 10°

Replacement discs are required for the rotary sharpener; for example, you can find a “rotary sharpener replacement disc set” on Amazon for just under €10.

In addition, ball bearings of type 6001 are needed. Genuine ball bearings are optimal (see the bill of materials); alternatively, suitable ball bearings can be 3D-printed—type 6001, with an outer/inner diameter of 28 mm/12 mm and a width of 8 mm.

The knife holders have a high side and a low side; the latter is designed for narrow blades.

Fifteen magnets, each 6 mm in diameter and 2 mm high, are required for the knife holder.

Under the knife holder, there are cutouts for anti-slip rubber pads (e.g., those used on Ikea cabinet doors—hot glue works as well).