spiralling cable interlock system

[saspinall]

Hi

Having trouble modelling a part which I require to send away for rapid prototyping. Unfortunately can't send a model or picture of what I want due to IP rights, but basically I'm trying to model a cable interlock portion. There'll be 3 interlocks spiralling down the length of the cable with a 1m pitch length of spiral, the interlock will also have cutout spiralling down it for the cable cores etc, so basically a 120 degree part of a tube with a couple of holes cutout.. Ive tried a method of creating a helical curve using sketch line down a straight datum curve and using the relation angle-dim = trajpar*360 then using the helical curve outer edge of the surface as the trajectory for the path of the section in a variable section sweep but when I put the 3 together in a pattern, patterned at 120, the sort of overlap and never get a true straigh end view, basically because the section is never parallel to the end, its always on a slight angle....Is it the way I set up my variable section sweep, should I be using Normal to trajectory...

Any advice or simple models would be greatly appreciated....

Stu

 

[saspinall]

Basically something like the section shown in the attached pdf. so this would be looking on the end of the interlock, which would then spiral on a helical curve with a pitch of 1m either into the screen or out of the screen.....I get something like what I want to see when I use a VSS along a helical surface derived from a sketch with trajpar in the sketch relations, just doesnt look quite right when put into a patter of 3 of these as 120 degrees, seem to overlap each other...