Tips and techniques for Blending

[sarvind]

I was interested in finding out if there is any tips / tricks information (website/ books etc) available on trouble shooting modeling issues faced during blending / hollowing of complex parts.

 

[Tetragrammaton]

Hi,

I can not say I know of any. Everything I learned about UG blending (since V9) has be on the job.

If you have a specific problem, maybe you can send me a little explanation of the problem.

Unfortunately in UG blending of all things can be a 'nice' challenge.

Best Regards

Dave

 

[cowski]

Blending is not an activity I look forward to, however there are some things to watch for that can make your life easier. Turning on all of the 'overflow' options helps. If the blend I want won't go on, I'll info the edge that I'm trying to blend (Information->object->[pick the edge]). If it is a tolerant edge, then you may want to look at how the model is built to simplify the edge geometry (it could be as simple as a mismatch). Tolerant edges are something that you will want to avoid whenever possible, the easy way to check for them is to validate the model (analysis->examine geometry->[select your model]) as this will highlight all of the tolerant edges.

If the edge is not tolerant, I'll start looking for small faces that the blend would 'swallow up'. The edge blend command generally will error out if applying the desired blend would eliminate an existing face. It is usually best if you can rework the model to get rid of the offending face, in my experience it usually turns out to be a small mismatch that shouldn't be there anyway.

A variable blend may solve your problem. You may be able to get the radius you want on most of the edge and let it transition to a smaller radius (or even down to zero) at the end. This usually works if you get the 'vertex too complex to create blend' error.

If none of the above works for you you may want to try a face blend or even a soft blend. These blends can eliminate faces that get in the way (so be careful).

In conclusion if you want a simple edge blend and it won't work, it may be a problem with the model and not with the blend command. There are so many options and possibilities that I cannot get into all of them in this short answer. If you have a sloppy model, blending can go from tedious work to nightmare very quickly but even with a good model problems will arise. As for problems with hollowing complex models, I avoid those headaches by never using the hollow command. But that should probably be saved for another post another time.