and retention by friction of inserts 46 with curved outer faces 47 the inserts 46 are preferably of synthetic plastic material which is resistant to impact wear and abrasion and has a low coefficient of friction with respect to the inner portions of the end eyes 33 in engagement therewith during use the vertical portions 44 of the rods 27 can be supported in any desired manner a preferred support being provided by the rivets 37 engaging the rods 27 and vertical flanges 39 of the attachments 25 referring now more particularly to fig4 and 6 of the drawings a heddle frame 20a is shown of well known construction and described in u s pat no 3 362 437 to f h kaufmann comprising top and bottom rails 21a formed as metal extrusions and side struts 22 connecting the ends of the rails 21a and maintaining them in spaced parallel relation the side struts 22 can be held in engagement with the rails 20a in any desired manner such as by screws not shown the rails 21a are advantageously made of light weight metal alloys such as those of aluminum or magnesium and with ribs 39a the heddle frame 20a is shown as having mounted thereon upper and lower heddle supporting rods 27a and which may have their ends extending into openings 28 in the side struts 22 and detachably held in place as shown in u s pat no 3 362 437 the heddle supporting rods 27a support a plurality of heddles 31.