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Helical Cut Creation


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I'm trying to create a helical cut along a part. I'd like the cut to extend along the y axis and turn about the same (y) axis. Furthermore, I'd like the section of the cut to be constant when viewed along the y axis. Is this possible? I've tried creating helical sweep cuts but the section of the cut doesn't create in the direction I want it to.

Under Attributes make sure you specify thru axis, this will make it normal to the y axis. Also you can specify right or left handed.
Thru Axis creates a cut, extruded along the y axis, that is a constant section when viewing the xy plane. I want my cut to be a constant section when viewed perpendicular to the xz plane. Sorry if this wasn't clear earlier.
I've seen a helical sweep created that mimicked what you want, but the geometry wasn't accurate to the sketch. Basically the sketch was at an angle to the y-axis.

I created a twist like this using a blend feature. However depending on the section, even the blend feature created some irregular cross sections. (never did figure that one out)

The third option I tried was a style feature. Creating the wireframe of the feature was time consuming and some companies don't own ISDX; but it made my geometry, constant / accurate sections and all.

I would suggest using the blend feature. It should have the best chance of working. It is a little more difficult to determine the pitch with a blend feature.

To get the geometry, create enough sections that the minimum rotation between any two sections is 45 degrees. If this is a tight pitch (creates several twists in the cut), don't create more than 1 pitch length (1 revolution) in the blend feature.

Copy the surfaces of the finished blended cut. Transform the surface copy along the y-axis one pitch length. The open ends of the surface transform should touch the bottom edges of the blended cut. Create a cut using the surface transform.

Finally, group and pattern the surface transform and the cut for as many revolutions as you need.

This is a lengthy workaround, but if you try to place all the sections in one blend feature, it will bring Pro/ENGINEER to its knees.

If anyone has a better method, I'd like to learn it.
Create a datum curve thru the axis of revolution

Create a coordinate system at the base of the curve

Create a datum curve from equation, use a cartesian csys






Create a Variable Section Sweep. Select Normal to Origin Traj. Use the first curve as the origin trajectory, use the helical curve as the x-trajectory. Sketch your section, and Viola!
Forgot to explain the equation



x=xor*cos(t*360*number of revolutions)

y=yor*sin(t*360*number of revolutions)

z=t*length along z

I use this equation because you can make an oval by varying xor and yor.
If you have a hard time with this shoot me an e-mail and I'll reply with an example part you can use. I do this all the time, my company makes a lot of drill bits. We are on version 2001.

[email protected]
ProFishent, can you send me the file of how to create the helical cut. I just want to learn more, if possible ca you please tell me the sequence??? Your help is appreciated!!
For creating a thread, should I make the curves (and length in formula) extend beyond the start and end surfaces? Also, how can the formula be changed to reflect a tapered (NPT) thread?