Spiral (Circular with a Step) Pattern

[Stuart]

Is it possible to do something like this picture in Alibre (without script)? Essentially a circular pattern with a step along the rotation axis.

Or repeat over a path along the face?

I'm at a loss as to how to go about it.

 

[NateLiquidGravity]

Create the center as a part and the "steps" as another. In an assembly constrain the first "step" onto the center and do a circular pattern using the layers properties.

 

[Stuart]

That would work, except I forgot to mention that I want to have a spiral of cuts.

Could I use a Boolean in the assembly to remove rather than add the "step" part?

 

[NateLiquidGravity]

Yep. Create your cut as a tool part. And then do a Boolean Subtract feature while editing the center. Constrain the tool part and circular pattern just like in an assembly.

 

[NateLiquidGravity]

FYI I specifically mentioned to do the boolean feature while editing the center part so that it stays parametric. If you do an assembly boolean feature you get a dumb solid export as a result.

 

[Stuart]

It worked! Thank you very much!

 

[Stuart]

Here's the end result

 

[Stuart]

Why are the layer and twist angle fields not available on the feature (noon boolean) circular pattern?

 

[Ralf]

Hi Stuart,

Design Explorer -> right click on the Feature -> Edit -> Twist Angle
.

 

[Stuart]

I want to do it in a single part, using a circular pattern of an extruded sketch. I don't want to have to create another part, and I'm wondering if there's a technical reason why the layer and angle aren't available for extruded sketches, or any other set of features for that matter.

 

[idslk]

I want to do it in a single part

there's a technical reason why the layer and angle aren't available

you have to enter a layer number greater than 1...

 

[Stuart]

Don't you have two parts, "pinn" and "pinn_gross"?

I want to add a hole in the cylinder using a sketch and extrude cut the hole in part "pinn_gross", then use a circular pattern on the extruded hole feature. That works as long as it's only a simple rotation. It doesn't have the layer and twist settings that circular pattern has in an assembly or boolean operation (using another part).

Why not? I can't think of any technical reason why these settings aren't available for a feature only pattern.

 

[idslk]

I thought you don't want to have it in an assembly...
Can't see a reason for this too, but also never needed it.

 

[idslk]

It's not the same, but you can get the result easy in sheet metal
I've drawn only one circle for the cut (and a reference line), the rest was patterned... ;-)

 

[Stuart]

I want a single part file.

It seems like an arbitrary decision to leave out those settings, making it a pain to do with a separate part. Instead of a simple sketch and extrude cut, you have to make a separate "solid" part that represents the "hole" that you want to cut. Since it's a completely separate part, you don't get the benefits of "to next" or "geometry" with a simple extrude cut. You have to shape the "cut" part exactly the way you need it for the boolean subtract.

That's a lot more work for what could be a simple step.

 

[Stuart]

It's not the same, but you can get the result easy in sheet metal
I've drawn only one circle for the cut (and a reference line), the rest was patterned... ;-)

View attachment 30297

This makes it even more silly that it's missing from a non-sheet metal part.

 

[idslk]

Well, as long as i have one tool to do the work, i can do my work...
And in the sample, the "the thin wall tube with holes", i thought it could be done perfect in sheet metal...

 

[Stuart]

If it was just a simple tube, that would solve it, but it was more than that. I just gave the portion of the part that was causing a headache.

I'm going to open a support request and see what they say.

 

[idslk]

As long as i can get holes that easy into the tube, it won't cause any headaches at my side...