Well this is a weird shaped thing. Maybe you can figure out how it fits with the other pieces  shown previously. Then again it would be helpful to guess what it is supposed to be first. Maybe it would help id I told you that part of it was going to be red when it is finished.

Spending time on the computer for a few days, writing folk art plans and working out the kinks in an automata mechanism.

Well what's this? First a pair of odd looking chairs, then half a leg and now this weird picture. It looks like a pair of man's legs sticking out from under a dress! Any guesses? Seems like someone's imagination might be getting carried away. Oh well you'll have to keeping following the blog to find out. 

Another chunk of the new automata to go with he chairs. This is a lower leg, feminine looking I hope, that is part of the same piece. The leg will pivot a the knee. The actuating arm is a thin piece of brass that has been epoxied into place in a slit cut in the top of the leg. This will all be hidden in the upper leg if things continue to go according to plan.  Keep following I'll add another piece of the clue tomorrow.

Hmmm? So what's with this? I can assure you that I have not gone into the business of doll house furniture. They are part of a new automata piece in progress. But what is with the holes? One circular and one rectangular. Well I guess you'll have to keep watching the blog to see where this is going.

When people are introduced one of my automata pieces they always ask, "How does it work? How do you figure it out?" This blog entry will take a stab at answering a bit of both questions. 

Lets take our character below, Otto Mata, and have him raise his hand to wave at his adoring public! To make Otto's hand, (Point A) rise in a waving gesture 1-1/4", (distance "a" in the diagram) how much do we need to cut into cam G. This amount will be distance "g" in the diagram, the difference between the minimum and maximum cam diameter.

The answer lies in understanding the length of the levers and fulcrums that are part of the linkages between these to points.  I'll perform the calculation with the arm in the neutral, position, that is half way up. There are minor corrections that can be applied for fact that many points are following arcs not straight lines, but they will be ignored in this example.

Since Point B is fixed on Otto's shoulder and only allowed to rotate, Point C will move down as Point A moves up. It will move in portion to the leverage around the fulcrum at Point B. For Point A to rise 1.25", Point C must move 1.25" x 1/3 = 0.4167" downward.

Point D on the cam follower will travel the same distance since C and D are pinned connections (i.e. distance "c" = "d"). Since the end of the follower, Point F, can only rotate, the amount Point E will move is also a function of the lever length. Because the two points are on the same side of the fulcrum at F, the calculation to determine the distance "e" is a little different that the previous one. Point E  will move (0.4167" x 2/(1.5 +2)) = .238"  Translating  this to the cam means that the difference between the minimum and maximum diameter on the cam must be 0.238", slightly less than 1/4"

If the nominal diameter of the cam was to be 2" then the cam should have a (2+0.238/2) = 2.129" outside diameter, and a  diameter of (2-0.238/2) = 1.88" where the arm is to be raised.

How fast Otto's arm rises and falls, and how long it stays up is a whole other story! Who knows, it could be a future blog posting.

 

After cranking out a few crows I decided to add a hen to my folk art repertoire because I had a block left over from the resawing. A hen and rooster are probably among the more common folk art images. Maybe it's because if you looked out a pioneer farmhouse window is is what you would see most often in the yard. Anyway here is Henrietta. 

I took some time off building automata to knock off a couple of folk art crows for someone. One is standing and the other  is crouching, sort of the look just before they leap into the air. I prefer what I call primitive folk art, very rough, lots of carving marks and simple in design. These small fellas are about 4" wide and 8" long. The standing one is about 6" high and the other is about 5" high.

What endears them to many is the look of their gnarly legs which are fashioned from coat hanger wire and butcher cord! 

Taking a quick break from automata for a few days to make a few folk art pieces I have made before. This time I photographed all the steps so I could create a plan and instruction set for possible sale. 

It took a little doing and some usual audio visual hiccups but finally the video for the recently completed automata piece "Fishing is posted on the Fishing page of my website. Please have a look and tell me what you think! Gertrude and Heathcliff are waiting for your visit!

I selected a handle design and set in to build it today. The result is a muskellunge, Mishe-Nahma, whose name is taken from the song of Hiawatha. Here is the finished photo. Tomorrow it will get glued on to the input shaft and the Fishing automata will be virtually complete.