Hi Swegmang, can you please post your 3DM model file so I can take a look at your actual geometry instead of only screenshots?

If you're trying to fillet along this line here:



the problem with that is the fillet needs to go on this surface here:



But that surface only touches the fillet edges at a single point instead of having an actual edge shared in common. MoI's filleter only knows how to construct fillets between surfaces that share an edge in common, it won't know how to make a fillet going on that surface above.

For fillet ordering, usually you want to do the largest radius ones first and smaller radius ones later. But if you're doing them all the same radius it tends to be better to do those all at once instead of separately, that tends to gives the filleter a better shot at stopping the fillet before they collide into each other and making a corner juncture patch where they all meet. If you do them separately it means the second round of fillets now is going to have to treat the corner patches as additional geometry to fillet across.

If you have a situation where the filleter just isn't going to be able to work you can instead trim away some area to make an opening and use Construct > Blend to put in a blend surface there instead of filleting.

I may be able to give better advice if I could see your geometry though.

- Michael

Thanks for all the advice, it's not so much that I don't know how to fillet them, its that I'd like to know if it's possible to change them after so that I can bevel it if i want to. So that my fillet isnt so destructive. I come from a poly modeling background so that's part of why I want to know. I thought about what you said and after thinking about it I think I am starting to see what you mean. Like I said, its not so much that I don't know the order I need, it's that I am trying to see if its possible to do them in reverse, so if I do make a mistake, I can correct the issue. I am also still trying to figure out how surfaces work haha.

I am not sure how to do the thing you mentioned. blending them, I am still figuring blending and all that. Here is my file.

Anyways like always I appreciate all your help!

Hi Swegmang, sorry no in MoI it's not easy to change a fillet after you've created it. If you think you're going to want to change it later it can be a good idea to save off an unfilleted version to a separate file so later on you can load that file back in and do a different fillet. Some other CAD programs like SolidWorks, Solid Edge, etc... can change fillets because of how they keep the history of operations. If changing fillets is a big issue for you some other program that has that type of history modification might work better for you than MoI.

Thanks for posting your file - I'm not quite sure what area in the file you're trying to fillet though.

- Michael