For the VBS preview events in January, we were able to borrow a wooden milking cow that we used in the VBS Expo.
Our cow was cut from plywood - there were four pieces that were slotted to fit together.
On the inside of the cow, a square wooden brace was screwed to two sides of the calf. Four holes were drilled in the bottom of a pink plastic bucket and 4 calf-feeder teats were rubber cemented into the holes. (Make sure that your rubber cement will glue plastic to rubber!) We filled the bucket with a solution of water and powdered milk, placed the bucket in the brace, and had ourselves a milking cow!
Emilie on our LifeWay VBS facebook page found these directions for making a wooden milking cow.
Sorry we don't have a pattern or more pictures - mine were lost in a hard drive crash! But many of you got great pictures of the cow - in fact, if you have some pics of how it was put together, could you send them to me at firstname.lastname@example.org? Of if anyone has already made a pattern of the cow that they would like to share with everyone, please send it to me at email@example.com.
APRIL 25 UPDATE:
Thanks to Allie for sending some pictures of the cow for me to post. I still don't have a pattern, so if anyone has one to share, send it on!
APRIL 26 UPDATE:
Here's a little video I found that might help a bit with making the cow - it was taken at our VBS preview event in January at Ridgecrest!