1" Double Spout

Such a part might be commercially available - I just didn't find one in my local hardware store and figured the project would be interesting. 

The smaller spout fits the tumble dryer's sewing tube (ca. Ø10 mm), the larger spout fits the one from the washing machine (ca. Ø22 mm). 

The print might or might not need support, angles are critical depending your printer/settings/material used. I used PETG without supports and had to do a little bit of sanding on the overhangs that got a bit rough. 

Design changes (late 2023, photographs still show the old version):

• Added internal spout (blue arrow) to prevent back flow from the washing machine (bigger duct) to the tumble dryer (smaller duct). This actually almost destroyed our dryer and took me a while to figure out. 

• Added 1" union nut, now it's a a convenient print in place design (had to be glued before). The small ring connecting the two parts (red arrow) provides support for the union nut top surface and can easily broken.

(Photographs still show the old version)