djm

Nope. I believe there are a lot of backers who never received anything. I ponied up $1000. I received none of the tracks or the special edition train related to the pledge. I've learned my lesson about backing kickstarter projects. David

The Auckland LUG held it's annual Brick Show over the weekend. I built a roller coaster ride based on BrickRide.com's design. One of our LUG members conducted a few interviews with some of the exhibitors and I was interviewed about the roller coaster. For those of you that might be interested, here is a video of the interview/the roller coaster. Regards, David

That part is available in the LDraw library, which lead me to i.e. https://www.bricklink.com/v2/catalog/catalogitem.page?P=6282#T=P&C=11 David

Having slept on it, here's an experimental path for me to explore further: The motor would be attached on the green axle on the right hand end. The left hand end of the green axle would run through to the differential. The gear shift would be on the (red) output axle with appropriate gearing to reverse the axle direction. I need to explore the reverse gearing a bit - if I can make it have the same ratio as the forward gearing, that should mean that any rotation from the clutch gears when in neutral should cancel out. I built this physically and it appears worthwhile exploring. However, further exploration my me will have to wait until the end of October, post our LUG's Brick Show. Regards, David Edit: et voilà. Bricks rather than liftarms to provide the same ratio.

I'm glad I put that caveat in. The modification wasn't buildable (a clash between a pin and axle which I hadn't spotted). I've corrected that and at the same time improved the support for one of the 8T gears, replacing the tan Technic, Axle Pin without Friction Ridges Lengthwise with a 3L axle. This required a rejig of some of the other parts but I have built it to the newer instructions and it now seems more reliable. I have replaced last night's building instructions with newer ones but retained the same link. One thing that puzzles me slightly is that even when in neutral, the gears and output axle still rotate. They rotate in the "forward" direction when my expectation was that they wouldn't rotate at all. You can feel there is significantly less force behind the rotation when it is in neutral than when in the forward direction but nonetheless the rotation occurs. If anyone could work out a way to make it rotate in the "reverse" direction when it is in neutral, that could address@RohanBeckett's desire for a quicker switch between forward and reverse. Regards, David

Something like this, which eliminates the crown gears, tweaks the bracing and changes the gearing post the 40 tooth gear. Build instructions Caveat: only built digitally right now. I have not tried the changes as a physical build. David

I just tried replacing the two crown gears with 3x 16 tooth gears and that works. The opposite gearbox position is then used but that is neither here nor there. Further, it removes an undesirable "feature" of the first build where the output axle was rotating in the opposite direction to the input axle. I can see some slippage between two 8 tooth gears (close to the 40 tooth gear) as they are on physically separate technic parts. I suspect I could improve this and eliminate that slippage. I'll have to think some on this one. Nothing immediately comes to mind. Regards, David

Thanks to both of you for the heads up. The link should work now. David

toyco is currently running one of their one day LEGO sales that seems to be across the board e.g. LEGO Mindstorms EV3 31313 for $480, down from the usual retail of $600. This link should list all the LEGO from highest to lowest price. The sale ends tomorrow. David

I think the Chain Holonomic Drive works but probably requires the torque deliverable from a motor. A ball passing through a turning mechanism coupled with a clutch just doesn't deliver the torque. David

Acknowledgements I’ll start this post with two call-outs to Nico71. Firstly, he posted images of his ball counting GBC module (refer to text further below) which provided a substantial foundation on which to base my module design. Secondly, he was gracious in giving me permission to post the building instructions for my module online. I wanted to obtain his approval given my module is, ultimately, a derivation of his original work. Module video and Building related files Firstly, a video of the module and links to the building instructions, parts list and LDraw file. Building instructions: PDF Parts list: BrickStock BSX file LDraw MPD file Context I had a desire to have a ball counting GBC module as part of the GBC display for the upcoming 2017 Auckland Brick Show. The primary features of the module were that it would; be a mechanical device i.e. no electronics in the module have discrete digits to indicate the count preferably rotate all digits in the same direction Development I was aware that Nico71 had built a GBC Ball Counter and had posted both photos and a video of it running. It seemed a sensible place to start so, after studying the photos and video, I reverse engineered the module to help me to understand how it worked. I knew that Nico71’s module was not using discrete positioning for digits but I was also aware of Parax77’s video and building instructions of his Chain Holonomic Drive, which I thought I could use in place of the wheel dials in Nico71’s model. Using the Chain Holonomic Drive however proved to be too unreliable. While I could get it to work reliably with two digits (the ones and tens) I couldn’t get the required reliability for the subsequent three digits. I subsequently discovered another video of a GBC counter by Nicky Fitzgerald and a second video providing more information about the build. I attempted to adapt the counting mechanism to replace the wheel dials but this was unsuccessful. The counting mechanism uses the "Technic, Axle Pin with Friction Ridges Lengthwise" in what appears to be a means to prevent the “hammer” from falling due to gravity. I found the amount of friction when attempting to turn multiple dials concurrently (e.g. 99, 999, …) too great for the upper clutch mechanism. However, Nicky Fitzgerald’s design did point me in the direction of the solution I ended up implementing in my module. Module Design Commonality and Differences The following image uses a coarsely grained colouring to identify the main elements of the module. The input bin is coloured red, the primary ball moving mechanism is coloured black and the counting mechanism grey. The primary ball moving mechanism (black) is pretty much the same mechanism as in Nico71’s original module. There are a couple of minor tweaks but nothing that is too significant. The input bin (red) differs in the following ways; it is larger, the agitator mechanism is different (and driven via the addition of a chain) and it contains a mechanism to restrict the balls to drop into the primary ball moving mechanism one-at-a-time and in time with said mechanism. The counting mechanism (grey) is a “plug compatible” replacement for the original, displaying a discrete count of the number of balls. Next Steps and Additional References I have used this module in test mode. It occasionally seems to spin a dial a bit too far but then the next ball moves the same dial less. I won’t get to use the module “in anger” until late October. In the meantime, if someone else elects to build this module and has any suggestions for improvements to the design, you are more than welcome to post back to this thread. Should someone be interested in exploring more about the counter mechanism built by Nick Fitzgerald, in the last couple of days I came across two related videos. Of course, you could always reverse engineer that module and post the building instructions (although after checking with Nicky). Regards, David

As promised, building instructions are now available for this mechanism. The LDraw file is also available. Feel free to Improve/alter this mechanism as you see fit. If you do, please post the results back on this thread. Regards, David

I've adapted the auto-reversing mechanism, replacing the sliding mechanism with a variation of Sariel's 4-speed sequential transmission. I'm satisfied that the resulting mechanism is more reliable than the original mechanism. Further, the problem where the differential continued to rotate by a small amount no longer occurs with this mechanism. Here is a short video of the mechanism in operation. I've got a couple of tweaks to make to it. Once that is done I'll post some building instructions for it. Regards, David

Accompanied by an article with an explanation and a series of photographs, which should make creating building instructions easier. David

Try https://www.bricklink.com/v2/catalog/catalogitem.page?P=2351#T=C Regards, David

Thanks for the suggestions. I has tried adding another gear to add some resistance but it tended to cause too much resistance. Similarly friction on the gear shifting mechanism while it would stop the incidental rotation, it caused the sliding arm movement to stick when moving between the two sides. However, your observation about friction made me think a little harder. I have significantly reduced the gearing "path" required to turn the differential in the opposite direction and this has solved the incidental rotation. I'm all for simpler mechanisms - it means there is less to go wrong! I'm now working on eliminated the slider mechanism altogether. Instead, I'm thinking of adapting Sariel's 4-speed sequential transmission, changing it to be 2-speed forward and reverse directions only, with the gear changer driven from the differential's gear. All dependent on parts from BrickLink orders arriving. Regards, David

As part of Splat's To-and-Fro GBC, the mechanism that provides a means to halt the GBC if there is a jam I found to be particularly interesting. RohanBeckett then posed a challenge (half in jest?) to adapt the mechanism to automatically reverse the GBC for a short period of time and then for it to resume normal behaviour. So I decided to take up the challenge and came up with the following. In the video, my hand simulates the case of a GBC mechanism becoming jammed by holding the output axle. Following the "jam" there is a pause, the output axle momentarily reverses, pauses once more before resuming the original rotational direction. This mechanism is in the experimental stage and there is a minor defect. The defect, as shown in this second video, is that the differential continues to turn a very small amount even when there is no jam. The gearing ratios are correct, so I suspect that the rotation is being caused simply by the rotation of the axle. I'm posting this thread for two reasons; 1) to garner possible solutions to address the defect 2) to see whether anyone else has interest to/is able to improve/alter the mechanism. I'd be open to any suggestions as to how the incidental rotation of the differential could be eliminated. I'd also be open to seeing other peoples' interpretations to make a mechanism to achieve a similar result. For convenience, I have made the build instructions (PDF format) and the LDraw file (MPD format) available for download from BrickSafe. There are also a couple of images of the two sides of the build: Regards, David

(I'm not a lawyer but ...) I'd imagine that the copyright holder of the models lies with Akiyuki and the copyright holder of these instructions lies with those who authored them. As the website which 9V fortunately spotted was selling the instructions, I believed that it was breaching the copyright of the later. Akiyuki is aware of this project. Refer to http://akiyuki.jp/en/541#comments. I also think that someone previously mentioned in a thread somewhere (though I can't find it at the moment) that they had communicated with Akiyuki in respect of producing instructions of his models. He indicated he was okay with this being done on the condition that the instructions explicitly recognize/acknowledge that he was the originator/designer of the model. Regards, David

That would be a Chinese website selling the instructions which we have collectively made and posted here for free. David I contacted the website's help desk and told them that the product was being sold illegally. They have said that they will end business with the supplier. We will have to see whether or not that actually happens. The text of the chat is shown below:

Here is a longer video of the same GBC circuit.

Do you have each layer contained within a subfile? If you don't, you can put it in a subfile and then include the subfile multiple times. The instructions will then generate a single instance of building steps for the bricks in one layer and show a multiplier for the number of layer instances. Using your example (assuming I have understood it correctly), this would result in one set of build steps for each segment (i.e. 5 build step sequences) and a multiplier for each instance (i.e. first sequence would show "X 15" at the end, second sequence would show "X 15" at the end, ...). Regards, David

You may want to take a look at this topic where something similar has been achieved. Regards, David

You may want to take a look at adapting the mechanism of torso's Cardan Lift GBC. It achieves two delays for each rotation, which would appear to suit the needs of your GBC. Regards, David

You are not alone, so patience seems to a key criteria. David

Dachshund [LEGO Club, 2010] Download MPD Known errors: none Modelled using LDCad 1.6 alpha 4