Hi Stien, filleting in areas that don't have a lot of room can tend to be more difficult to calculate.
One thing you might try is to select more edges to fillet in one operation rather than one at a time like it looks like you're doing. Doing them in one operation will usually give the filleter a better chance at trying to make a corner patch where the fillets collide into each other. When you do them individually the next fillet has the geometry of the previous fillet to try and deal with as well which adds complexity. It's also harder to fillet things when you're not selecting all edges that meet up at a common juncture, having 2 fillets collide into one another with an additional sharp edge coming off of it also adds complexity.
So for example in a case like this:
Then the best situation for filleting is to have all these edges filleted at once:
That's going to allow the filleter to have space to make a juncture between the fillet pieces:
If you need to leave some edges sharp instead, you may need to export your model to a different CAD program that's better at making those types of fillets, like OnShape for example. MoI's current fillet engine is going to have some difficulty with your sharp edges.
> ...does the seam on the cylinder have to be in a specific place?
Well it's good for it to not be right next to the fillet since the fillet won't be able to cross over it, it looks like you've been putting them in good spots.
> ...is there a perfect number that for some reason wont infinitely calculate?
No, it's just that as things get compressed with small distances to work with it makes things more difficult for the filleter to connect things up. When you fillet only some edges instead of all of them, it will easily happen that the fillets will be of different arc lengths where they collide into each other and then making corner junctures is much more difficult.
> ...Should it be a specific type of fillet?(Circular, G1, Constant..)
Circular probably gives you the best chance.
> ...Does the calculation just take a long time?
No, probably not in this case, it's probably just confused about how to deal with corner patches in a tight area and trying to build some messy result.
> ...is it effected by using non corner points in the creation of the solid?
Sorry I don't understand what non corner points means here.
> ...will this operation work better on a surface? instead of solid
It is possible to do filleting between 2 surfaces rather than doing edges of a solid, that does a different type of fillet calculation called a surface/surface fillet. That can succeed in situations where the edge based one will fail but it will only make the fillet surfaces for you and you'll have to manually trim them and try to fashion juncture areas yourself.
> ...how does flow change what is possible ?
Once you introduce bending it makes it more likely that 2 fillets will not be the same arc length where they collide and so it makes it much more difficult to handle the collision between them.
> ...do booleans create a fundamentally different object than extruding?
Hmmm, not particularly. But a boolean is going to give you trimmed surfaces and the side walls of an extrusion are more simple untrimmed surfaces. The cap of an extrusion is a trimmed surface though as well.
> ...Should i always start with a "draw solid" primitive?
Only if it happens to be easier to do. Extrusions from 2D curves are a good way to build things.
> .. is it curving too hard that i need different fillet values on each side, then a certain range will
Well, any curvature at all means the 2 surfaces being filleted do not meet at a single angle, their angle varies throughout the length of the fillet and that means the fillet will have different arc lengths. All the cross sections of the fillet will be of an arc of the same radius but it will be a longer or shorter arc of that radius in different areas.
You may want to do your fillets on your straight object and then warp the whole thing with fillets using Flow.
- Michael