Unable to fillet

[c_glensmith]

Hi, I'm trying to model the shape of a "root trainer", I've got to a stage where I want to fillet a transition but getting an error:

Unable fillet complex shape, error message: "Error: The fillet/chamfer could not be created at the requested size. This might be occurring at the ends of the selected edges. Try adjusting the size or using multiple separate operations. Check that the selected edge chain ends at a sensible position, and if not try selecting more edges."

I get the same error if only the straight joint on the side is selected. 

[TrippyLighting · Accepted solution]

Your geometry is pretty unclean due to your modeling workflow. If you create a Inspect->Section view and move it through the object, you'll see that you have (likely) unintended internal voids.

Also, a simple fillet might work but the geometry will look pretty bad.

I've modeled something very similar using a most 1/8th of the features. If you go through the timline of the attached model you should be able to see the workflow.

[c_glensmith]

Thank you, I am really looking forward to looking through how you did this later.

I know my work flow got messy, I really struggled to workout how to do this.

[jasonhomrighaus]

Sketches and lofts are your friend!😀

[c_glensmith]

@ jasonhomrighaus  not always! I had 53 sketches in my attempt above! but Peter above showed it only needed 3 sketches. The difference is he knows how to use surfaces and lofts (and a lot more) properly.

[c_glensmith]

Hi Peter

I looked through your workflow, it is really impressive and very educational, thank you so much.

I have tried to replicate it but I can't get my SurfaceStitch to create a solid body. My surface stitch completes without error but the resulting body is still a surface body.

f3d file is attached, can you see where I'm going wrong?

I have other questions but this is the one I'm stuck on and I don't want to be a nuisance! 

[TrippyLighting]

The outer circles in the top loft profile create overlapping surfaces.

there are several ways to fix that, but I would probably trim the circle extension in the sketch and make sure it is tangent to the line.

[c_glensmith]

Thank you again. 🙂

[jasonhomrighaus]

Actually always. That is what Peter was showing you. If you setup your sketches properly then lofts work wonderfully. I’ve spent many an hour twiddling with sketches to determine that most of the time, when they don’t work it is because I did something to cause it. 

[c_glensmith]

Hi Peter

Can I ask how you created the two sketches in you workflow?

They only have 4 parameters, how have you copied the arc 7 times?

I can either draw 7 separate arcs, or one arc copied with a rectangular array, but either creates many more parameters on the sketch.

I'd like to draw one 1 arc and use a rectangular array to copy (because I want to experiment with different numbers of the ribs on the out side) it but then if I constrain the end point of the outer arcs the other arcs are similarly truncated.

Best regards

Chris

[TrippyLighting · Accepted solution]

I manually sketched 3-point arcs but only dimensioned one. Then I used the equal constraint to set the others to the same size. Then I continued to constrain stuff until the sketch was fully defined.

There are three things I avoid using in sketches. Patterns, mirrors and the offset command.

[c_glensmith]

Ah!, thank you.

Edit: OK, I resolved the below by changing the length of the construction line in the first sketch but I'm frustrated . Why on earth would the end point of a construction line matter like this?

I feel I'm taking advantage of your generosity but can you assist again? I started again and this time getting something very weird on the loft. The ribs on one side are malformed, see screen grabs below and f3d file attached.

[TrippyLighting]

You need to make sure that the sketch is fully constrained. It isn't in the file you attached.

The line should be midpoint constrained to the origin and the arc end should be constrained to the construction line.

The pay attention to the loft settings.