Update: It works! Unfortunately it is a bit small for oranges, but scaling it up should do the trick. The size of the holes is small enough to keep the seeds out of your drink, but too much pulp passes the filter, at least for my taste.
The design doesn't slice through the oranges quite as nicely as Samuels juicer ( thingiverse.com/thing:20853 ) does, but it is much easier to clean.
There will be an improved version of this thing in the near future.