You just missed your chance to see some, at Old York village in Maine. There were at least two there, that I saw in the corner of one of the buildings.
If the Shaker village doesn't have one then in the book by Joesph Moxon are some pictures of these.
http://www.amazon.com/Mechanick-Exercises-Joseph-Moxon/dp/1879335859/ref=ed_oe_pHe talks about there construction and use. It should give you all the information you need.
I have some other information in another book, but I recently loaned it out and will have to get it back.
I will be contacting this person soon and I just picked up a tool then wanted. And when I go over to drop it off, I'll get my book back and scan in some pictures and send them to you via regular email, as the images are copyright protected so I can't post them here.
Jim Rogers