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Retrograde-A K'nex Ball Machine

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Picture of Retrograde-A K'nex Ball Machine
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     Ladies and gentlemen (and the Instructables robot as well), I am proud to present my fourth ball machine on this site. Retrograde incorporates all the skills and inspirations I have acquired so far. In addition, Retrograde includes some brand new elements! 
     The ball machine is 3'5" (104cm) tall and 2'9" (84cm) wide. It has about 3,700 pieces, and would have had more aside from the fact that I almost ran out at the end. The machine has seven paths, which will (according to my custom) be dealt with in separate steps. I also used the Stepper Lift, and will be making instructions once I take the machine down, since there are none on Instructables already.
     So sit back, relax, and enjoy watching...Retrograde!



Note: Retrograde refers to the term retrograde motion, which is the process that make the planets appear to circle back on their orbits through the sky. I thought the name appropriate, because a lot of the ball machine's elements use circular motion.
The music in the video is Chopin’s Fantasy-Impromptu for piano in C sharp minor, Op. 66, CT. 46 and Mazurka for piano No. 23 in D major, Op. 33-2, CT. 73.
 
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Step 1: The Stepper Lift

Picture of The Stepper Lift
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     For Retrograde I tried several lifts, and finally settled upon the Stepper Lift. Through some careful analysis of I_am_Canadian's Twister pictures, I was able to reconstruct a fairly accurate rebuild. I built it four grey rods high (which is seven lifter mechanisms).
     Since I always build on a red rod support structure, this lift posed several design challenges. I had to get the lift to connect to the rest of the machine! I settled on the 4 grey rod height because 5 red rods is roughly the same as 3 1/2 grey rods...which was the height of one side of the lift. I simply put connecting rods across the gap.
     The other problem was the width - the yellow rod lift would not match my red rod structure, either. I solved this dilemma by placing the lift at a 45o angle to the rest of the machine. In this position, it fit perfectly. I curved the entrance and exit paths and voila! I could defy gravity!

Note: My gate mechanism may be a little different from I_am_Canadian's...that was out of necessity. There weren't any really good pictures of it, so I improvised... :-D

knexpert#10829476 created a motor housing and posted a picture in the comments thread.
Sorunome9 months ago
This vid is blocked too D:
hunter9999 months ago
Nice, soooo great, I like it
:-) Glad you think so!
lopertt1 year ago
Movie maker isn't really good for high resolution video... haha. Use a program like Adobe Premere CS6 if you want to export in full HD. It also comes with a few more professional looking titles.
http://www.youtube.com/watch?v=Hhw0yq_ByTs
Get it for free at the above youtube video. :D
tedbear21 year ago
the 'portal' door is my favourite part of this.
This think is really, really good. Fine job good sir!! Thanks for the inspiration.

..Check your inbox :-)
Thanks! :-D
Also for future instructables, try to use zoom on your camera rather than just being close to the part because being close to the part won't constitute a clear picture. It's just like when you look at something really close it will be blurry. Just a friendly tip:-)
I did for the additions, sometimes the lighting and positioning are just problematic... :-}
Thanks for the advice, though...it did help on some shots.
can i have instructions
If it is alright with MarsCrystalMan for instructions then yes, I will make some since I copied it with some mods.
thanks
can you make it an instuctable
This is as close as you'll get to step-by-step instructions, although in a month or two I will post the instructions for the Wormhole and the Stepper Lift, and maybe the Dropper Path Separator.
See knexpert#10829476's pictures below...He built the whole machine from the pictures in the instructable! ;)
Don't you worry about that, I will take care of it for you:)
Thanks...I just don't have time to go back and make a true step-by-step how to build it of this machine. Also, I just added some more pictures like you asked for...a little late, but if you still need them. ;-)
Thanks for posting these! They really helped! I never knew that the holding path had the orange connectors on it, maybe it will work this time:)
Glad they helped! :-)
I'm glad your aim in knex isn't all guns. Don't we have enough guns people?
Agreed...the guns are cool, but it is easier to be a pioneer in an area of K'nex with less volume of work already done. :-D Besides, while K'nex guns are often amazing, ball machines defeat them almost hands-down for "wow" factor (in my opinion, anyway)!
Here is a working configuration of motor attachment since the little yellow gears strained it.
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Perfect! Thanks for showing your motor housing! ;-)
You sucked up all of my green connectorsXD. That has never happened to me before! Anyway, I enjoyed copying this. It's not exact because of some blurry pictures but it's 98% correct.
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One last thing, can you post a couple more pictures that are a little clearer than the very blurry ones, like use the zoom on the camera rather than just being close to the part? I want to try to copy this awesome machine.
I certainly can - just tell me which pictures you think need replacement (or at least the worst steps), and I will be happy to improve the instructable for you! :-) Also, I can take entirely different views...it can just be a kinda broad task, so it would be nice to have some more specifics.
Also, thanks for wanting to build it...You've probably set a record for number of reconstructed MCM ball machines! ;-D
More pictures of the back with the track behind the wormhole, the track leading to that and the green path near the bottom how it connects to the yellow connector path. I also copied it with a couple mods to make it lean towards knex balls. I will post a picture of it in about 20 minutes. Thanks for posting!
Can you please make an insttructable on just the wormhole element? I am very curious. Also, your best ball machine to date:D
Sure I can! It may be a while though...for the moment I can't bear the thought of dismantling the machine. :-( But maybe I can deconstruct and rebuild just that portion. Perhaps I even have enough elements now to start my own guide! :-D
Thanks for the compliments as well!
Yeah, I would probably shed tears if I took it down too early to. Thanks!
KneXtreme1 year ago
Awesome ball machine! The wormhole is one of the coolest elements I've seen in a long time. Keep up the good work :)
Thanks! :-D Glad you like it!
Well done! Lots of interesting things in there. My favorite is the dropping ball collector. It's cool when mistakes lead to new elements. :-)
Definitely! ;-)
Great!
The wormhole is awesome, as well as the dropper path seperator.
I like the spiral element, can I try to build one for normal knex balls?
Thanks for the building (a modified version of) the inverted ball dropper! :p
Thanks!
And you can most certainly build a "glowstick spiral" for K'nex balls! It should only require a slightly wider gap between each loop of the spiral.
Yeah I was wondering if knex balls have a different diameter then these golfballs, but I don't think there's much difference.
Well, golf balls are about an eighth an inch smaller than original knex balls, and a little more than twice as heavy. Small differences in size and weight can make a difference though. For instance, Mr. Muggle's "Uh" element (the one on which the ball rolls back and forth falling through) won't work with golf balls because of the smaller diameter; they fall right through the center!
And like the spinning basket, there you can see the difference in weight.
BTW this deserves a feature :D
Yep, the spinning basket really does highlight the difference - it turned out so nicely, though. ;-) And thanks for recommending for a feature! :-D I really tried to upgrade the video quality in addition to the ball machine quality for Retrograde. Glad you like it!
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