Need help creating steps on a Nose Cone

aiden_cheung

Hi, I'm working on a school project where I need to model a bunch of tiny steps onto a nose cone. The finished product will basically be a nose cone with a bunch of concentric ridges (1000+). I have the nose cone modeled, but I'm having trouble creating the little ridges. I've tried using feature pattern, but it doesn't seem to work. Can I have some help?

Link: https://cad.onshape.com/documents/7391e5a0490b42447ce0ff5b/w/53872c7c5b423e4986a5c184/e/04adc8ae18645be2e5e6e869?renderMode=0&uiState=6a978080c791f3c69a051e4f

(apologies for my bad MSpaint drawings)

eric_pesty

Something like this works:

https://cad.onshape.com/documents/ad3a4c455ad1e14181bedc48/w/19fd44026ba55ab9b27e03c7/e/c43e6b099cc977f4dcb60e29?renderMode=0&tangentEdgeStyle=1&uiState=6a984e3fbc6e5c992198a2ae

eric_pesty

The example above was for even vertical steps, if you want even radial steps you can start from teh top like this:

https://cad.onshape.com/documents/ad3a4c455ad1e14181bedc48/w/19fd44026ba55ab9b27e03c7/e/0c0175715ffc6db767fd50c2?renderMode=0&tangentEdgeStyle=1&uiState=6a985d01bb72967cd80baa27

martin_kopplow

Hmmm ... not sure what purpose these ridges serve and what rules they are to follow. Constant ridge angle? Constant slope width?

A crude approach could be like:

https://cad.onshape.com/documents/10bae9d9e0b07b8a7c24d03f/w/21d888cf5894e838d19a5893/e/50453c33cf033b2dfcd20774?renderMode=0&uiState=6a9801b52ced98cbcc980fa5

If we knew what rules apply, there could be a more parametric approach.

GregBrown

This would be a pretty simple Custom feature to write. Like a basic slicer - I think a few people have done so in the pas (and I know this guy "Claude"….)

martin_kopplow

Yes, probably a Feature Script. I think it would need to be a bit more elaborate than a basic slicer, because delta Z would possibly have to be modified for each slice.

Nameorus

maybe I could help if you actually let me copy your document.

eric_pesty

I was going to suggest using the Topographinator FS but it's kind of the "reverse" of that…
It could be a good starting point to create an FS for that.

I think this could also be done with a pattern and variables though, as shown here:

https://www.youtube.com/watch?v=l1vVKmfVeWM

eric_pesty

Something like this works:

https://cad.onshape.com/documents/ad3a4c455ad1e14181bedc48/w/19fd44026ba55ab9b27e03c7/e/c43e6b099cc977f4dcb60e29?renderMode=0&tangentEdgeStyle=1&uiState=6a984e3fbc6e5c992198a2ae

martin_kopplow

Yes, that's also nice, with the corner of the copied rectangle always being trapped on the curve.

eric_pesty

The example above was for even vertical steps, if you want even radial steps you can start from teh top like this:

https://cad.onshape.com/documents/ad3a4c455ad1e14181bedc48/w/19fd44026ba55ab9b27e03c7/e/0c0175715ffc6db767fd50c2?renderMode=0&tangentEdgeStyle=1&uiState=6a985d01bb72967cd80baa27

aiden_cheung

Hi, thanks everyone for the replies. Apologies for the specifics, I'm relatively new to this. Since someone was asking, I'm actually modelling 3d printed nosecones for fluid analysis!