I’ve come a long way in a few days but these protrusions in my model are defeating me. I think they are like mobius strips and I can’t seem to remove them even after intersecting faces with the model. Any tips?
Thing.skp (481.5 KB)
There’s a lot of strange stuff going on in the geometry that needs fixing. More than you indicated in the screenshot. Frankly, if this was my model I would start over from scratch to make it cleaner.
If you aren’t going to start fresh, intersect faces and remove what you can. Then replace faces where needed by drawing in edges with the Line tool.
I was thinking that would probably be what I needed to do.
I started this model a week ago and have been iterating on it. All the jankyness from having no idea what I was doing is still present. I suppose I can use it as a reference for measurements to make a brand new version. I was hoping to avoid that, but I think I just needed someone to tell me the obvious.
Have you ever heard the term “sunk costs”? It makes it hard to let go of what you’ve done and start over but taking what you’ve learned and making a cleaner model is probably the path of least resistance.
Using what you’ve done as a reference is a good idea. Make sure you check the dimensions you need to see that they make sense. I’ve been going through your model making checks to see about making an example for you but I’m finding a lot of what look like strange dimensions.
Before you start over, remember to reset the axes. I would model this thing centered on the origin and set display precision as high as it goes so you can see if there are small errors. For the arcs and circles use segment counts that are a multiple of 12. Using 96 sides for the circles should be plenty. That wil get you smooth enough surfaces for 3D printing and help to avoid tiny face issues.
(When I model screw threads for 3D printing I use 96 sides and get very smooth, usable threads)
Good luck.
Some of the odd dimensions are on purpose, some of them are artifacts of tomfoolery.
I will take that all into account and try again.
1 Like
Just for the heck of it I modeled a version of your ring. I expect the dimensions are not exactly right since I was trying to figure them out from the screwy dimensions. I’m using Bool Tools 2 to cut the holes because that extension honors components. It does tend to soften edges a little more aggressively than I wanted but that’s easy enough to fix. The pyramidal recesses were added to the big cutter volume. I could have combined the counterbores with the large cutter but I prefer to split things up a little.
Thanks for the help. I went back to the drawing board with everything I’ve learned over the last week and gave it another go. I had a MUCH better experience and it came up miles better.
I only used a “cutting” tool to drill the holes. I see you like to make a cutting tool for a lot more of the part. Is there a reason for that?
Thanks for the advice and encouragement. Onwards!
1 Like
I often find it easier to visualize and model the volumes of cutters. Sometimes I see those volumes as the cores that would be required if an object was going to be cast. I see analogs between a lot of the tools or methods in SU and the tools or methods one might use in a shop working on real stuff. It’s just what works for me.