5/23/05 I was using an actuator with an 11" stroke very simply, very nice.
5/30/05 I'm switching to an actuator that has a 9" stroke but also turns and is very very quiet.
It started off with circuit boards attached, gripper claws and 5-6 sensors and 4 stops for controlling position.
I removed them. Some parts will be added again later. I removed the mounting plate from the bottom and flipped it around. This helped with center of gravity and made it just a little shorter. I tapped new screw holes for the plate into the actuator. It was nice that it had its own curved plate for mounting..
Two screws to remove actuator mount 
When the plate is removed you need to 
pop two pins out with a small screw driver.
Then flip the plate, you will find the holes for the screws still match.
Above: Mounting plate flipped around. Robotic claw and stepper motor removed and extra metal cut clean off.
Above: I'm positioning the actuators so that they fit and their movement is free. Now I'm glad the CSS is aluminum because I'm tapping holes and screwing the actuators into the plates.
The 9" stroke linear actuator starts off longer and more awkward than the 11" stroke actuator that I once sold. It's superior because it also turns 360 and has two guide rails instead on one. I shorten the actuator's length by removing the encoder off the back motor. I gained more control over the 360 movement by replacing the servo motor with a gear head brake motor. I lost the quiet smooth speed of the servo but not the arm can stay in a locked 12 o'clock position without slipping to 6 o'clock.
A teamdelta.com hub is used at the elbow with a dewert motor. I modified it with a hack saw.
Hubs were $45.00
These are part numbers RCM304 and RCM304H (Specify a 10mm bore.)
The motor is a dewert...order info on this page.
Video of arm movements.
Picture 1 - The elbow. The motor is mounted to the forearm. The shaft goes through an oversized hole to the hub. The hub is connected to a plate that is connected to the 1" aluminum arm.
Picture 2 - The arm is mounted by taping 4-20 holes into the actuator plate. The arm itself is two 1" square aluminum stock this is done to help keep everything straight..
Picture 3 - I guess it bares repeating this motor replaces a servo motor ..also on this arm I moved the mount from the other side of the actuator to this side. It just required taping more screw holes. To replace the motor I had to drill new holes into the old mounting plate. I had to switch drive gears at the end of the shafts. So the holes had to be made larger in the gear and a set screw had to be created. (Drill and tap the gear.)
Old turning motor 
New turning motor 
Below the brake motor was removed and the old mount was a template for new holes. Brake motor is mounted with 6-32 thread screws (maybe 5/8th in length). You need to counter sink the holes on the same side as the old countersunk holes.
Drive belt gear was removed, Conical mount pushed out and a large hole was drilled half way down the larger opening to make the gear fit the wide shaft.
I drilled a hole in the side of the drive gear and threaded it for 8-32. A short set screw disappears into the side and fastens the gear to the shaft.
On one actuator I moved the brake motor to the other side of the actuator. So there is a right and left actuator.. It's just two 6/32 threaded holes. Very easy. If I didn't do this the motor would hit the support bars in the CSS. If you look below the brake motor is not insight because it is on the backside of the actuator...not in the center of the robot.
Above..can you see how I'm going to operate the claws?
6/7/2005 Second arm finished, another naked robot video here.
Picture 4 - To shorten the length I flipped the mount to face front.
To protect the arms from wear against the torso while turning like a clock, I installed the top 3/4" of a plastic coffee can. It lets the arm turn easier also.
Joe has been working on his arms using these as a platform.
I think I may have a solution for increasing the extension of the arms. Im experimenting with mounting the actuators on a drawer-slide platform. the entire actuator would slide forward when extending the arms. Im also mounting the "elbow" motor on the actuator slide platform.
Tread section:
I'm using wheels to hold most of the load and the tread sort of grip lightly and pull it along.
I have clamps holding the motor mounts in place in this photo.
Here is a video at 12 volts...moves faster at 24 volts but...to show you 24 volts I need to charge a battery and have someone hold the camera.
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