Downholder for Eugster OEM coffee machine brewing units

thingiverse

Downholder manufacturers Eugster and Frismag produce high-quality coffee machines. Their products include Bosch Benvenuto, Siemens Surpresso, Nivona CafeRomatica, Krups Orchestro, Krups XP, Melitta Caffeo Solo, Lattea, CI, Bistro, and Lounge series with a brewing unit similar to the one shown (with or without grip). This component sits inside the brewing unit and is responsible for pressure regulation. The original part is made from ABS but tends to crack over time, causing coffee taste and crema to deteriorate (this can also be caused by a worn grinder). Additionally, half-empty cups and a hissing, "steamy" noise from the brewing unit while brewing occur. If your coffee started losing flavor gradually, it's likely due to a worn grinder. However, if the loss happened quickly and is accompanied by other symptoms, it might be the downholder. Remove the brewing unit and inspect the downholder for cracks. They can be seen without disassembling anything and should be apparent. If it's the grinder that needs replacement, you can replace the grindstones yourself for about 30€ in roughly an hour of work and carefully re-adjusting the grinder afterwards. There are many guides available covering this process. There are two versions of how the part functions. One uses a black rubber flap that lies on the center block and attaches to the part through the holes beside the block (pull through with tweezers). The other uses a clear silicon piece on top of the white part inside the brewing unit, with nothing attached to the downholder. The downholder must withstand significant force from below, so it should be printed with very high or full infill. It should lie flat on the fully flat side of the part with large holes. I recommend at least 2mm of top and bottom skin to ensure sturdiness. External support is required. As the part regulates pressure and affects coffee taste, I recommend printing it with a layer size of 100µm or less to maintain distances close to the original part. It must sit firmly in the brewing unit. Regarding material, PLA should be sufficient in terms of strength; however, the downholder may be exposed to heat, so check for any deformation after a few brewings. The part itself does not come into contact with coffee, so food-grade material is not strictly necessary.