Hi Peter, there is a bug in text that I've fixed for the next beta which should help out for some calculations.

You can work around the bug currently by creating curves instead of solids, then selecting the curves and doing Edit / Separate followed by Edit / Join, and then extruding those curves into solids. That will fix up one particular problem with the current Text command.

But I'm not sure if you are running into that problem, or just a general fillet difficulty.

Fillets tend to be a rather fragile and difficult area of calculation, if your font has a lot of little swoopy pieces in it, I wouldn't be surprised if it would be difficult to fillet it, you might only be able to fillet it at a pretty small radius.

I don't happen to have the Aachen font on my system here, can you please post a .3dm file that has a character you want to fillet and I will be able to give you more information by examining it.

But in general fillet works best in more simple situations where there aren't a lot of little edges and little pieces and sharp corners all over the place - Text can pretty easily be rather complex in this sense. Additionally a lot of fonts were not really ever meant to be used for 3D construction so they sometimes are made out of a bunch of little fragments instead of longer truly smooth pieces.

- Michael