Rotor Robot Belt Replacement

[Fineas J. Whoopie]

Just picked up a Rotor Robot. The rubber bands that rotate the eyes were all dried up and broken. I'd like to replace them but not sure how to go about it. It appears that the arms have to be removed so that the rod that moves the arms and (through the rubber bands) the eyes can be slipped to the side so that the new bands can be looped around the blue plastic cylinder. This rod is threaded through a hole in two tabs that are a part of the main frame . The arms don't feel like they want to come off without a dangerous amount of force.

I was wondering if anyone has replaced these bands and could give some advice?. Thanks.

[martijn]

I have no experience with this robot,

what surprised me about chinese robby spacetanks is that their rubber bands around the wheels are stapled togeteher (with iron clamps (is that english??sorry))

and they work perfect.

so if you dont want to force and break the arms apart, maybe try this same method, or instead of iron use needle and little cotton wire, then the surface stays equal.

rubber from a bicycle innertube is very strong, and will last long, you can cut all dimensions you want.

[David Kirk]

That seems like good advice. Don't tear the thing apart. I'll bet even if you need the softness of a rubber band, you could find a solvent that could hold it together after it was cut. What about tire patch solvent? I've had my robot since I bought it new around 1970. I'll bet it needs a new rubber band too!

[Joe K.]

Super Glue might work.

[robothut]

Yes you can cut a new rubber band then supper glue it back, the only down side is that the rubber band will age and go bad again. I seem to recal haveing used a elastic band once to repair one.

[Fineas J. Whoopie]

Thanks for the tips guys.

John - did you use super glue on the elastic? Did you glue it end to end or overlap it? It seems like a joint that is thicker than the rest of the band might bind between the gears and the cylinder.

[Blechroboter]

Make sure that it is real rubber. You can smell it. Soft PVC will solve the plastic. ;)

Noticed some cheap "rubber" bands made of soft PVC coming from China.

[robothunter]

Fineas, both Joe K. and John are correct. Super glue will hold just fine. In fact, there's a certain replacement parts dealer that I'm willing to bet we've all bought from at one time or another whose replacement rubber drive bands for the Mechanized Robby are simply cut and superglued rubberbands at $80.00 a pop! Imagine my surprise. <_<

Back before I knew this, I personally forced off the arms on my old Roto-Robot to change the bands and after cracking off the arm joint (it was really forced onto that metal drive shaft!) I had to perform surgery with a tiny brush and Testor's liquid plastic cement to put him back together. I really wish I knew the superglued rubberband trick back then! ;)

And yes, Martijn, not only do the Chinese spacetanks sometimes have metal clamped treds, but I've also had a few examples that had one peice tank treds. Go figure... :huh:

[Kilroy]

a while back I bought a kit to make your own "o" rings at a garage sale, unfortunately the solvent was dried up but I did find super glue worked quite well. It employed a technique of cutting the O ring off at a perfect 90 degrees with a razor blade and gluing the ends together without an overlap.

[Joe K.]

I agree with Leon. An O-ring is the way to go. Will outlast a rubber band by decades! You might be able to find a "thin" enough one at Lowes or Home Depot.

This site will answer any and all of your O-ring questions:

http://www.oringsusa.com/html/products.html

[robothut]

O rings can be cut and supper glued and they never come apart, I have even done this on a pinball machine when I was waiting for the right rubber slingshot ring to arrive and I wanted to play the game. But the problem with a O ring in this case is that it might tend to crawl off the drive pully, that pull is realy designed for a flat belt like a rubber band. Now if you had a sheet of thin rubber (maybe an old inertube) you could cut a belt 3/16 inches wide and glue to lenth. That would last along time. Try the O ring but don't be surprized if it tends to crawl off the drive pully or get jamed between the pully and the gears.

[Fineas J. Whoopie]

Well I went with a pair of wide rubber bands. I cut them, threaded them under the drive cylinder and glued them back together. I did this a few times until I had the rubber band trimmed down to the right tension. The tricky part is getting the head re-assembled with the bands looped over the eye stems. I also scuffed up the drive cylinder a bit for better friction as the rubber band was pretty smooth. In this case the O rings would not have worked because there really is no more than a sixteenth of an inch (if that) between the cylinder and a gear below it. I did use O rings to get the ears spinning on my Mechanized Robot a few years ago.

This Rotor Robot was sold as non functioning.

The main problem was a gummed up motor which I revived in a matter of minutes and now that the drive belts for the eyes are replaced, it's fully functioning. :D

Thanks for all the tips guys. :)

[robobob]

Nice job, Fin ... Glad he is working again.

Of course, this would be the OTHER way of doing it.

Your way was much less invasive !! :)

[Tinman]

Good to hear the robot is back in action Don. It's pretty cool whan they come back to life!

[Fineas J. Whoopie]

Thanks Bill.

Hey Bob, just out of curiosity, how did you get the arms off your Rotor robot? Did you pop off the round insert at the top of the arm and it disassembled from there? Did you break or crack anything during the process? Just curious because at one point I thought I would have to do this to mine to get the eyes working.

Also how does the mechanism that revolves the legs work? Kind of strange that they move freely while not in operation but revolve when the robot is turned on.