switch the original of the pattern and have that change propagate through the pattern

erik_knudsen

Hi there,

I am trying to make a largish pattern of a rather simple shape. In the end there will be some 1300-odd copies in a 4-fold rotational symmetric pattern with 2 mirror planes.

What I've tried so far is to build the pattern out of parts and sketch-entities. My problem is that it very quickly becomes sluggish to work with, and one idea to speed the pattern building process up was to model the pattern using very simple dummy original, and once I am convinced that the pattern is correct, replace the dummies with the real parts or sketches.

Is this possible?

The pattern is created using a linear pattern along one line and then a set of linear pattern operations in a perpendicular direction to create a triangular pattern, which should then be mirrored and replicated.

https://cad.onshape.com/documents/4b4dbf4e8816a3846df7b5c5/w/f3b7f06bab8d48f1d2bf03dd/e/bac9fae68a6f3786506fb581?renderMode=0&uiState=636a5799a7313e1761ddfa77

mahir

I have a few suggestions. And yes, Onshape makes it relatively easy to replace references in a pattern. However, you'd likely have to do it on a per pattern basis.

1. You would have more options working in a part studio vs an assembly. Generally, if you don't need to incorporate motion or mates, part studio gives you way more patterning alternatives. That being said...
2. Instead of multiple patterns, this looks like it could be done with a single fill pattern with an appropriate border. There are also ways to incorporate formulas and variables so your pattern follows a specific equation. In this case that looks something like abs(x-a)+b.
3. Sketches are cumbersome and slow compared to surfaces and solids. So use part patterns when possible, followed by face pattern. Feature patterns are a last resort

eric_pesty

You might be better off creating a "helper surface" (for example) in a part studio with your pattern represented by simple holes (in the location you want whatever instances in the end) and use that to drive a "replicate" feature in your assembly, that should be a lot quicker to work with and it will pattern whatever you mate to that surface...

mahir

If you'll be patterning different items, @eric_pesty has a good suggestion with the helper surface. This is a good way to populate an assembly pattern with different configurations/types/zones of stringers. Just make sure different zones are represented by different size holes. You can then replicate automatically in the assembly. Here's one implementation using a combination of fill pattern and helper surface. 

https://cad.onshape.com/documents/49b92d0b122a08a66768b4ee/w/bb5fda224c934b86f984e03f/e/420a48f720002f71ae43b37e

mahir

I have a few suggestions. And yes, Onshape makes it relatively easy to replace references in a pattern. However, you'd likely have to do it on a per pattern basis.

1. You would have more options working in a part studio vs an assembly. Generally, if you don't need to incorporate motion or mates, part studio gives you way more patterning alternatives. That being said...
2. Instead of multiple patterns, this looks like it could be done with a single fill pattern with an appropriate border. There are also ways to incorporate formulas and variables so your pattern follows a specific equation. In this case that looks something like abs(x-a)+b.
3. Sketches are cumbersome and slow compared to surfaces and solids. So use part patterns when possible, followed by face pattern. Feature patterns are a last resort

eric_pesty

You might be better off creating a "helper surface" (for example) in a part studio with your pattern represented by simple holes (in the location you want whatever instances in the end) and use that to drive a "replicate" feature in your assembly, that should be a lot quicker to work with and it will pattern whatever you mate to that surface...

erik_knudsen

mahir said:

I have a few suggestions. And yes, Onshape makes it relatively easy to replace references in a pattern. However, you'd likely have to do it on a per pattern basis.

1. You would have more options working in a part studio vs an assembly. Generally, if you don't need to incorporate motion or mates, part studio gives you way more patterning alternatives. That being said...
2. Instead of multiple patterns, this looks like it could be done with a single fill pattern with an appropriate border. There are also ways to incorporate formulas and variables so your pattern follows a specific equation. In this case that looks something like abs(x-a)+b.
3. Sketches are cumbersome and slow compared to surfaces and solids. So use part patterns when possible, followed by face pattern. Feature patterns are a last resort

Hi Mahir,

Thanks for the suggestions.

Wrt 2. This I simply don't know how to do. It's a feature I did not know existed. And yes - it is a simple equation.

Wrt 3. I had been told it was the other way around - that's why I did it this way.

mahir

If you'll be patterning different items, @eric_pesty has a good suggestion with the helper surface. This is a good way to populate an assembly pattern with different configurations/types/zones of stringers. Just make sure different zones are represented by different size holes. You can then replicate automatically in the assembly. Here's one implementation using a combination of fill pattern and helper surface. 

https://cad.onshape.com/documents/49b92d0b122a08a66768b4ee/w/bb5fda224c934b86f984e03f/e/420a48f720002f71ae43b37e