SOLVED!
Circling back to you guys, I’ve done the following.
After contacting a construction engineer, he said this [freely translated]:
The cause of the blobs is the flat top surface of the base, which shrinks during cooling down. Therefore, a ‘saucer’-like formation occurs. The edge (outer walls) will therefore rise slightly. The print layer thickness is slightly too small, resulting in too little volume available for the filament wire. Possible solutions are:
1. No top surface - which I’ve stumbled upon myself already
2. Thin base
3. Concave in the base
4. Bulge in the base
5. Annular grooves in bottom
Long story short, I’ve experimented with the 3rd option: the base slopes downwards!
And guess what? Problem solved!
