If it were me, I'd contact Michael and request a revised model without the ribs. It would be a LOT easier to remove them digitally and print a new part than manually remove them with a saw. He responded promptly to messages when I was talking with him, so maybe he's simply on vacation at the moment?
That would be a very delicate surgery, bit if anyone could do it, you could!
Hi Darren,do you know what kind of material Shapeways is using?
So I will either extend the cleaning time still significantly, or sometimes have to try Aceton, or are there any ideas of the Shapeways experts here in the forum?