Seems you can use the free FormZFree! ;)
http://www.formz.com/products/formzfree.html



or inside the Free SketchuP 2017 Make + free TopoShaper by Fredo
https://www.sketchup.com/download/all#fr
https://sketchucation.com/forums/viewtopic.php?f=323&t=52039