doug72 Posted February 13, 2017 Posted February 13, 2017 (edited) Following my failure to get the PV Productions GBC10 Ferris wheel to function I set out to build my own creation using the GBC10 idea as a starting point. I chose to drive the ferris wheel via chain drive with a 72:1 reduction from the M motor. Loading & unloading is done by trip arms not via a gear train and lever arrangement. Getting the correct locations for the trip pins / rollers was a lengthy trial & error process but eventually got them working OK. A ball return was installed to allow for continuous running. The GBC is mounted on a 28M x 56M baseplate and will eventually be linked to various other GBC modules I have built to form a longer GBC ball run. I used the new PV balls as they performed the best - I have some Lego balls from the Maze set and white balls from Itsy but they tended to hang up. The Lego balls have a marginally bigger diameter and sometimes would not pass through the loading gate. Occasionally balls stick due the small hole but next ball along sets it in motion again Video: General view: Oblique view showing M motor drive via 72;1 reduction then chain drive to ferris wheel. Side view showing chain drive: M motor via 72:1 reduction then large Lego chain to rotate the ferris wheel. Ball loading mechanism: Operated by a trip arm activated by rollers on the ferris wheel arms and with an adjustable linkage rod to set correct time for the ball gate to open. Ball guides added both sides at the loading point to ensure balls don't over shoot. Ball unloading trip: trip arm on bucket unloads the ball. This took a lot of time to get the ball discharge ramp in the correct position, used studded plates to get 1/2 L offsets. Edited February 13, 2017 by Doug72 embedded video Quote
DaFokka Posted February 14, 2017 Posted February 14, 2017 Wow, I can imagine that must be a pain to get to work reliably. Thanks for not putting any music under the video! Quote
doug72 Posted February 14, 2017 Author Posted February 14, 2017 41 minutes ago, DaFokka said: Wow, I can imagine that must be a pain to get to work reliably. Thanks for not putting any music under the video! Thankfully I have no idea or desire to add music. Re Timing: the hardest is getting the balls to unload consitently, with some going around for a second time. Because of the shape of the claw with its pointed tip, it is very tight getting the tip not to catch a arm rotates and at same time release the ball onto the runway. Eventally added a rubber tire to the trip roller which improved the unloading, with only the odd ball not discharging . Now working on an alternative ball carrier that should overcome that. I had to "borrow" the claws from my Gyrotiller MOC where they will be re-fitted. Quote
doug72 Posted February 16, 2017 Author Posted February 16, 2017 (edited) Update: Following further prolonged testing a number of problems arose, culminating in a spectacular disintegration of the tower when a bucket claw jammed but the drive kept on running as I had neglected to put a white clutch gear in the reduction gearing. Result due to the angled drive chain it pulled the tower over !! Other problems were the bucket claws rubbing on the wheel arms causing balls to flip out and the tips catching on the discharge point causing jams. So Ferris Wheel Mk. 2 was evolved: Drive chain eliminated - new ball buckets devised which located & hold balls in the correct position for discharging. New stronger tower built which includes M motor driving via 72:1 reduction with a 24 white clutch gear as the final drive to the ferris wheel. If any jams occur now the wheel stops rotating. Ferris wheel arms modified so that ball buckets sides no longer rubs on the arms. Lego cyclist fitted with a safety helmet ! IMG_4351 by Doug Ridgway, on Flickr IMG_4350 by Doug Ridgway, on Flickr Close up showing ball sitting on the red bushes. IMG_4349 by Doug Ridgway, on Flickr New Video: Edited February 16, 2017 by Doug72 Quote
aeh5040 Posted February 17, 2017 Posted February 17, 2017 Very interesting module! I especially like the release mechanism. Why do two of the 3L pins of the release mechanism have a small gray wheel, and the other two not? Quote
doug72 Posted February 17, 2017 Author Posted February 17, 2017 2 hours ago, aeh5040 said: Very interesting module! I especially like the release mechanism. Why do two of the 3L pins of the release mechanism have a small gray wheel, and the other two not? Well spotted, basically I forgot to put them on the pins ! When devising the ball carrier design I only used two arms to perfect them, once OK I added other two carriers. Took some time to get the balance correct for the ball carriers so they loaded & unload balls without hanging up. Now added the missing grey wheels and functions OK for ball loading on all 4 arms. Works OK with them on or off the 3L pins but with them in place the action is smoother as the roller on each arm hits the trip arm. Took a lot of trial & error to get the ball loading mechanism working consitently. Timing can be adjusted by shifting the link on the black 12L axle for the bottom lever. Quote
MIchaelF Posted February 17, 2017 Posted February 17, 2017 Love this idea Doug! I may go back and rebuild the GBC 10 with the red driveshaft and your mechanism for buckets. Quote
doug72 Posted February 17, 2017 Author Posted February 17, 2017 (edited) 3 hours ago, MIchaelF said: Love this idea Doug! I may go back and rebuild the GBC 10 with the red driveshaft and your mechanism for buckets. Thanks, I find building on studded base plates provides riigidity and allows for easy adjustments & positioning of parts. The base plates are non Lego but compatible and low cost. They are just the right size for building stand alone GBC modules which can later be linked up into a larger GBC circuit. With the ball loading system I used there is virtually no back lash affecting timings, which you can get with complex gear trains. If you want any close up images let me know. Edited February 17, 2017 by Doug72 Quote
LucyCol Posted February 17, 2017 Posted February 17, 2017 Nice idea, like the Mark 2, and its good to know you have the cyclists health and safety taken care off Quote
doug72 Posted February 17, 2017 Author Posted February 17, 2017 35 minutes ago, LucyCol said: Nice idea, like the Mark 2, and its good to know you have the cyclists health and safety taken care off As a keen cyclist and Volunteer Ranger on the UK cycle network I know the value of wearing a helmet. Quote
RohanBeckett Posted February 18, 2017 Posted February 18, 2017 that said.. I'm not too sure of the intelligence of that little minifig.. he may be wearing a helmet... but he'll still have concussion after a day of this running! :D Quote
Captainowie Posted February 18, 2017 Posted February 18, 2017 On 17/02/2017 at 2:29 AM, Doug72 said: Following further prolonged testing a number of problems arose, Yep, that's what happens with GBC! Quote
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