Yes, we have checked the length of cut pieces, and we have found the variation in length. in attached file i have attached encoder details and cutter. the cutter position which is seen in attached file, on this position encoder PPI must be zero. i have set PPI zero on this position of cutter, but after making one cut, while i have checked, i have found that its not zero on this position. that is why we have suspect that there was a problem of missed counts. the encoder which is show in attached file is used only for cutter positioning.