bencpv
Mechanical
- Feb 5, 2013
- 10
Can anyone help?
i am trying to create sizing die for plastic extrusion. The die is basically an open cylinder with grooves (at a pitch/spacing of 6.35mm) running along the interior face. There are also holes in a six-start spiral pattern running along the length (to create a vacuum whilst extruding). The angle of twist of each spiral arm is 60 degrees. The holes are to match with the groove centres on the inside, so that when the hole is drilled from the outside it will end up in the centre of one of the grooves.
I can control the spacing of the holes along the curved surface, but its hit and miss whether they line up correctly with the grooves (i.e. i dont know how to control the x dimension of the spacing so that it is exactly 6.35)
I need to be able to vary the length of the die, while maintaining the 60 degree twist and also ensuring that the holes match up with the grooves.
Does anyone know of an equation to help me out? or a method perhaps?
Thanks in advance
i am trying to create sizing die for plastic extrusion. The die is basically an open cylinder with grooves (at a pitch/spacing of 6.35mm) running along the interior face. There are also holes in a six-start spiral pattern running along the length (to create a vacuum whilst extruding). The angle of twist of each spiral arm is 60 degrees. The holes are to match with the groove centres on the inside, so that when the hole is drilled from the outside it will end up in the centre of one of the grooves.
I can control the spacing of the holes along the curved surface, but its hit and miss whether they line up correctly with the grooves (i.e. i dont know how to control the x dimension of the spacing so that it is exactly 6.35)
I need to be able to vary the length of the die, while maintaining the 60 degree twist and also ensuring that the holes match up with the grooves.
Does anyone know of an equation to help me out? or a method perhaps?
Thanks in advance