Little WALL-E

Unhappy with the results of directly mounting the arms to the servos, we started over using some very nifty chains and sprockets to offset things a bit. Also upgraded to HiTec HS-56HB servos for increased durability and their unique mounting options...

By the way, you can get the miniature mechanicals at ServoCity: Servo Sprockets (.1227) Plain Bore Sprockets (.1227) Plastic Chain (.1227)

Dude, i totally LOVE that design. Serious kudos!

You mentioned you were unhappy with mounting the arms on the servos, could you please give more details? How is direct mount different from the chain drive? I am working on a Wall-e project too.

Thanks

I would have preferred directly connecting them for the sake of simplicity but the lack of space made for several structural compromises that weakened the mechanism a little too much for my tastes. Also, by offsetting the servos I was able to keep much of the original mounting components/design with slight Dremel/X-ACTO modifications. Yes, that means the arms still pop off at the shoulder joint so they can be easily re-positioned without messing with the servos!

That being said, since they are no longer connected directly, the effects of external wrenching or twisting to the arms should largely be absorbed by the arm mounts and chain before hitting the servos. A link in the chain (or the arm itself) should pop off before any serious (kinetic) damage can be translated to the servo. The HS-56HB servo's stronger gears should help in that regard as well. Mounting the servos towards the front also frees up that valuable accessible real estate towards the back for mounting bigger batteries and your EZ-B...

Finally finished his left arm after an all-night miniature mechanicals marathon! In a state of delirium working on the other left and right arms now. Heheh...

Servos and sprockets... Oh me! Oh my!

My what mini chains you have there...

That'll do it Jerry...

Lookin' good Gov'na!!

Great to see that setup in action! works very well

Got his alternate-location left arm linked in and working! One more to go...

My third arm...

Dude, that's some serious engineering

What happened to your finger?

Thanks... Just a few minor X-ACTO knife nicks - they were fresh and I wanted to make sure no chemicals got in during my Retr0brightening, especially since I was on my last pair of gloves and had already popped the tip for that finger!

where did you get the chain and gears ?

ServoCity! Links are at the end of Post #2...

How did you take the original motor/white gear block in the Wall-e? I uninstalled all screws but couldn't take it out? Is it glued so Dremel is requried?

Thanks ZZ

Very cool project! I cant wait to see it finished

zzl630, I don't remember there being any glue on the ones I removed. Give it a thorough look-over - there may be a hard-to-find screw or two you missed.

Thanks TXTCLA55, I'm itching to get the first version of this wrapped up too! Hopefully I'll have something worth sharing soon...

Radmeck: I am going to use the gear and chain idea also... how many tooth gears did you use? I can almost count them in the pic... almost! Thanks!