A little change in the project has brought on a name change. The frog has some stones around him in the bottle now. They were put in by the little frog’s captor to be a token gesture to create a pleasant environment while enduring this frustrating captivity.
This frog is clever. He has grabbed a stone and taps it on the inside of the glass to attract the attention of someone passing by who might free him. So a little pebble in his hand has moved him from a lab specimen in a jar to a child’s captive curiosity. Therefore I have relabelled the project “The Captive”.
Here is the latest photo. He sits in the bottle while I fit his arms. His right hand is made and lies on the workbench beside the bottle. It will be installed so his palm pushes on the glass. A prototype for his left arm sits in place to determine length and angle for the permenant arm. It will move to tap the pebble on the glass.
Once the arms are prepared the frog will be removed and the mechanism will be tested and secured and the final assembly will begin.
Well, I'm still plugging away on the internals of my frog in a bottle. As I said before I'm going back and forth between the character and the mechanism. You can see below that the mechanism is coming along. There is even a couple of cams in the middle of that clump placed on the main shaft. A dowel is sitting in the place for a future pillar that holds the top just to give you an idea of things. The bushing in the foreground is for another pillar.
The followers front to back in the photo are for; the frogs right arm, the eyelids, the mouth, the eyeballs and the left foot. I need to work on the frog to locate the actuation point for the frogs foot and the amount of movement needed to make the cam. So below you can see some recent work on the frog.
So here's what is happening with the frog. He has a new rock to sit on the provide some interest in the piece and you can see he is getting two lower limbs. The left one will move up and down. They are being glued in place, so the foil in the photo is to prevent the feet from being glued to the base. That will come later after the mechanism for the foot is designed and the channels are cut in the rock.
More to come!
I’ve started assembling the plug-in that will drop into the jar with the frog on it. It also contains all the mechanism. These are the smallest gears I have ever cut from birch plywood. The smaller gear is 10 tooth, 3/16” wide and just under 1” in diameter.
The base is 4-1/2” in diameter. The small collars on the base are for pillars that with support the top plate where the frog will sit. The shaft for the large gear will extend to the left side. The little shaft was a temporary fit-up piece.
Uncharacteristicly I am jumping around a little on this one ( no pun intended) switching between the mechanism and completing the frog. I guess we will see what happens in the shop today.
A view blogs back I showed you a glass jar that will contain the latest automata project. It is actually a punch dispenser. I have a plan to have the hand crank protrude from where the spigot normally fits through.
Here is my first attempt at the handle mechanism. The handle is spring loaded. The bushing will be fixed into the hole in the glass urn. The shaft needs to be retractable so the mechanism can be dropped into place, and the shaft can spring back to engage the mechanism in the jar.
In the photo the piece on the right will be attached to the mechanism. The square block on the end of the shaft will engage the square hole on the mechanism piece to impart the turning motion. The large bushing around the shaft will protrude through the glass, with a lock ring (not shown), on the outside. A second smaller lock ring glued to the shaft will hold the shaft from protruding beyond the bushing as it is in the photo.
No going back now! Undertaking this assembly requires lots of thinking and testing of parts as you go. There is no way to get back to the upper mechanism without cutting our frog apart.
Here is most of Chester the frog glued together in one piece. Since the previous blog entry he has been shaped and sanded and has a rough coat of paint on him. It may be a little early for paint , but I was going to be away from the shop for a while so I took some supplies with me. He needs another sand to get rid of some of those grain marks once the paint hardens and a final paint. His eyeballs don't have pupils in them yet which gives him rather vacant look.
He is resting on a little stand, (basically a board with a hole in it) that allows all the brass actuators to hang out the bottom of him so they do not get damaged. This includes: an eyelid open/close actuator (the two rods from the head were soldered together in the space inside the torso to act as one), the eyeball left /right actuator, the mouth open/close actuator, the arm raise/lower actuator and the rod to hang arm counterweights on.
His upper legs are made but not attached yet and his lower legs are roughed in. His arms are yet to come.
A little more work on my automata frog specimen.
This next piece of work may not be obvious to you. My intention is to have this little frog in a glass jar. This means he has to fit down into the jar through the neck, but I do want to have his hand tap on the inside of the jar. This requires that the arm has to be installed after his body is in place.
This creates a couple of mechanical issues. His arm has to be correctly positioned on the arm movement shaft so as to have the right range of motion. For this I am putting a square shaft in place which will have a slightly larger square shaft in the arm to slide over it once the frog is installed. I will have to set up the right movement before the mechanism goes into the jar. The second issue will be pushing his arm onto the protruding shaft without pushing the shaft back into the body which will be unaccessible at that time. For this there is a little wooden stop to install at this point of the assembly.
Also as I am unsure if any counterweights will be need to balance the arm, or get the right "smack" on the glass, I have made some space for counter weights to be added later if necessary hanging inside the body on a brass rod.
The first photo shows the key pieces of the mechanism. There is a small brass strip with three 1/16" diameter holes. A 1/16th" rod, will a flat end protrudes from the centre rear, while the other end is soldered into a small square brass section. The square piece will be where the larger square tube in the arm will fit over. Through the side of the body block is a 5/32" diameter tube that the smaller square section will fit through. It will extend into the inside the body, not like shown in the photo here . It is pushed to the outside so that the arm shaft installed from the inside, can be as long as possible for now. After installing the shaft from the inside, the tube will be pushed in flush with the outside of the body. The two 3/64" rods are for the actuator linkage and possible counterweights.
The next photo shows the shaft installed, tube pushed into the body, and the actuator and counterweight rods attached. The tube extends into the body and the end acts as a bushing to keep the mechanism away from the interior body wall and other internal parts.
The photo below shows the wooden stop referred to above that prevents the shaft assembly from being pushed inward when install the outer arm. Its odd shape is designed to maximize the gluing surface to the body wall while allowing room for other actuator parts extending down from the head.
Lastly here is the arm mechanism in place in the roughed in body block. Now it is time to carefully glue the head blocks on and complete the final body shaping when dry.
Just to review what is being built I’ve posted these three photos of parts just before gluing things together. The first is a view of the frog’s head with the eyes in place. The second is a view of the underside of the same piece. You can see the brass links which control the eyes and the mouth movement. The eyes will move by twisting one rod which goes directly into one eyeball and linking across to the other.
The last photo is the upper head piece with the eyelids installed. The long links need to be installed now before gluing parts together. You can see some sanding marks where I removed some material during test fitting. It’s important to check that everything works well now.
Follow up later!
The last post showed a chunk of wood with little description. Well here is the scoop.
Often when making automata characters I find it necessary to assemble things as I go to hide mechanisms. This means, of course, that you won’t get at them ever again so you’d better have things right. In this case this little automata frog has eyes at move side to side, a moth that opens and eyelids that go up and down. There is no way to assemble all of this with the body together.
This frog body is three pieces, an abdomen, a lower head piece, and a head top piece. The eye, blink and mouth mechanisms have to be assembled before the head pieces are put together. Here are eyeballs lids and top of head with some paint done laid out in front of the lower head piece before assembly. The jaw is temporarily in place, not painted yet.
The next photo is a view of the pieces held together to check all the clearances before assembly. The linkages required inside the head can now be fitted. It is often challenging to continue to work to finish the body with linkage wires sticking out.
When I was at Automatacon this spring I saw a wonderful automata of a boy trapped in a glass jar. I was impressed and filed the idea of trying something similar away in the back of my brain. Well it is finally starting to dribble back out.
This is a gas container I have found to try something out. It is actually a lemonade urn, the convenience of which is that it already has a hole in the side where the spigot fit in. This will be the entry for my hand crank. Not sure how this will turn out yet. I am sort of making it up as I go along. I don't know the space requirements for the mechanism or the character until I progress a little more so nothing is permanent yet. For now I made preliminary internal structure that will hold the contents that will be fitted in through the lid. Here's a photo of the first steps.
For those who love a mystery, the second picture is the start of something that I hope will end up inside. I won't declare anything yet in case it all goes haywire!
As my last automata project was nearing completion my brother passed on a Pachinko Machine that had been hiding in his basement for numerous years. It was a fixture in his house in the seventies and amused his three children endlessly. Video games were just getting stated back then so it was quite a novelty!
With a little TLC and cleaning it now has been resurrected to former glory and Pachinko balls are clanging around again! You can never have enough Gizmos around!
Automata is a creative blend of my life interests , engineering, art and woodworking.