a dye container 13 the operating unit 11 takes the columnar objects 20 to move in a first direction labeled a the dye container 13 holds dye 30 therein the dyeing unit 12 moves in a second direction labeled b in order to coat the dye 30 onto the outer surface of each columnar object 20 the second direction is the reverse of the first direction the operating unit 11 includes a first top chain 111 a first bottom chain 112 a second top chain 115 a second bottom chain 116 a plurality of first holders 113 a plurality of second holders 117 and a motor 114 all of the first top chain 111 the first top chain 111 the second top chain 115 and the second bottom chain 116 are endless the first top chain 111 is parallel with the first bottom chains 112 the second top chain 115 and the second bottom chain 116 the first top chain 111 is located above the first bottom chain 112 and the first holders 113 are located between the first top chain 111 and the first bottom chain 112 each of the first holders 113 is used for supporting one end of each of the columnar objects 20 the second top chain 115 is located above the second bottom chain 116 and the second holders 117 are located between the second top chain 115 and the second bottom chain 116 each of the second holders 117 is for supporting the other end of each of the columnar objects 20 in other words one end of each columnar object 20 is sandwiched between the first top chains 111 and the first bottom chain 112 and the other end of each columnar object 20 is sandwiched between the second top chain 115 and.