Usually at very hard potatoes or larger potatoes, seems that either the bow or the knife block up the ghost. With me first was the knife block. When using the device my 20's knife block has gone kapput (a series was bent and fell out). My efforts spare parts from the manufacturer or otherwise available on the Internet were unsuccessful. Contact with Westmark by the seller was very disappointing. The text which I at the return request (for spare parts) was ignored. The seller has tried to clarify whether the unit is to give back. Nacdem I sent a photo of the knife block Hies it that such a loss can only occur due to improper usage ... Hmmm, yes ... I wonder then why offer farmers and supermarkets such hard potatoes? This could improperly behavior towards Westmark's French Schneider .... Each case due to the lack of spare parts distribution and response to complaints the company Westmark no longer exists for me.