by AEMCOEUROPA, published
How to print fully usable wormgear without soluble filling material? Look this....
Just print two pieces of half-gear, after printing stick with chloroform....(best glue for ABS ) already tested, work well.
No need any ballast material, You can make good quality worm gear with one simple reprap printer. ( after You designed, necessary to slice to two half-part in Your CAD software )