spiral part pattern 1

[alansimpson]

I wish to pattern a part in an assembly in a spiral pattern. Like a radial pattern with the radius incrementally increasing with each increment of radial angle. I thought of pattern along a curve but I cant figure how to place a pattern on a sketch curve and use that as a reference for patterning part.

 

[fredericmenage]

Hi,

Create a part file with the appropriate helical protrusion (the cross section should be a square or something similar so you have an edge you can use for pattern along curve). Then create a pattern along the edge of the helical protrusion of something small (small protrusion).

Insert that part in your asm and use it as a reference for 'pattern parts'. Then you can break the dependancy by dropping the pattern (RMB). Finally, remove that helical part from your asm.

HTH

Fred

 

[fredericmenage]

One more thing,

You can also do it with surfaces so that you do not see the solid in the assembly. And indicate in occurence properties that the part is just a reference.

Finally, I noticed that you might have to edit the part (pattern along curve settings) from the assembly to get the proper result.

Fred

 

[alansimpson]

I managed to get something near what I want. However I cannot produce a helical feature where the helix only progresses radially and not along axis, like a watch spring or a rolled up sheet.

 

[fredericmenage]

Hi,

After having built the helical feature with the progression along the axis, create a sketch on top view plane and include all the edges you see.

Using this flat sketch, you can create the flat helical using a simple protrusion.

NB: you might have to delete most of the 1st helical with a cutout (do not delete everything though). then create the flat helical. Finally, delete the remaining if the original helix with a 2nd cutout.

Fred

 

[beachcomber]

Hi alansimpson
Is it a spiral you want to create rather than a helix ?
You can create a spiral using the 'curve by table' command.
or construct it using arcs etc.
I'd suggest using a sketch for any complex path, then you don't risk losing all your construction if it all fails.
I seem to remember a previous post about creating a spiral curve.
I have the equations for an equiangular spiral if you want them and have set up a curve by table to try it out.
This curve has a constant angle between the radial line at any point and the tangent to the curve at that point.
Like a snail or conche shell.

beachcomber.

 

[fwc]

Is this what you're looking for?

URL=http://img80.echo.cx/my.php?image=spiral2ij.jpg

 

[alansimpson]

Yes that is the shape.

 

[fwc]

Hi alansimpson

You can create the helix with taper. Pls check the image below,

http://img227.echo.cx/my.php?image=helix045fg.jpg

Use Include command in the Sketch environment to trace the helix.

HTH

fwc