Blakbird

Instructions for Akiyuki's Pneumatic Module are now tested and complete and are available here along with a Brickstore parts list. 48 pages 543 parts Most of the credit for reverse engineering this module goes to jesuskyr who did the work making the LDraw file based on Akiyuki's video and creating most of the instruction steps. After building the module, I made a significant number of changes: Most obviously, I added a motorized compressor under the support stand which contains two small compressor cylinders and a PF M motor. I moved the position of the tower with respect to the hoppers one stud because there was some interference during motion. I changed the tilt angle of the output hopper slightly to improve performance. I replaced the yellow #5 and #6 long panels on the output hopper with the shorter #3 and #4. These are much easier to get and work just as well. Alternatively, you could replace all the yellow parts with another color. I used pneumatic tubes of several colors in the instructions to make it easier to see how connect them. You can easily choose to use all black in you actual build (I did). I was worried that this model wouldn't be very sturdy since there is no double railed frame like most of the other modules. While it is true that the model is not very rigid, because it is so light (especially at the ends) it is really not a problem to move it around. The timing on this module is very touchy and is largely controlled by the parts shown in red below. These can be slid along the axle to change the point at which the pneumatic valve is operated. It is also important to use the right tooth on the gear racks. There is really no way to describe in advance where these need to be; you just need to experiment with them until it works. It is very obvious once you get it right because it works perfectly. The rare Technic handles shown in green are just used as stops. You can easily substitute the new 1L DBG liftarm instead. This model is very sensitive to friction in the turntable. I started by going through my pile of turntables and picking one that seemed smooth. As I built the module, I tested it regularly to make sure it was working. When the top was held inverted, everything seemed fine. Then when I turned it over and rested the weight on the turntable, it wouldn't work at all. The pneumatic actuator did not have enough power to turn the arm. At first I thought I had a bad actuator, but I removed them and tested them and they were very powerful. Next I took the turntable apart and spent the next hour using coarse sandpaper, fine sandpaper, and then steel wool to increase clearance and polish. After that, it works very well. I suspect that the new Type 3 turntable would work much better and could be dropped in as a direct replacement with no other changes. This module is really fun to watch. The complexity of the motion while being driven by only a single pressurized input is very clever.

No way to tell from your video, but typically this kind of motion is caused by elasticity in the drive train. Because the static and dynamic friction coefficients are different, it takes a certain amount of torque to get the model moving and then a smaller amount of torque to keep it moving. During the first phase, the drive axles wind up like a spring. When motion begins, this energy is released and causes a sudden acceleration. Once that energy dissipates, the model slows down again, possibly even stopping to begin the cycle again. If this is what is happening, the only thing you can do is use stiffer components (i.e. metal) and/or reduce friction (i.e. bearings).

Amazingly detailed. I love the exhaust!

Something is not right about this. The motor torque should be directly proportional to voltage. The voltage determines the strength of the electromagnetic field which determines how hard the output pinion tries to turn. You can read about it here. It says, in part: For the same motor, ideally if you apply double the voltage you'll double the no-load speed, double the torque, and quadruple the power. Perhaps Philo can explain the reasoning behind the values in his charts! I think the only torque he directly measured was the stall torque at 9V.

Sounds like the consensus is in: include the compressor. I should have these instructions done this week. The air tank is only useful for storing pressure for intermittent use. In this module the need is continuous so it wouldn't do any good. My compressor uses two pumps. I was prepared to use as many as four, but I wanted it to be the right speed with a single M-motor. With 2 small pumps, the speed is just right. Any faster and you start getting impacts which slide the whole module around the table. I also finished building the step module tonight. I had to make substantial modifications to get it to work right, so those instructions will take a bit longer. I also have the marble run drafted and will test it in a couple of weeks.

Something surprising has happened. I actually designed something. I finished building the pneumatic module yesterday, and while I got it working very nicely, it had to be pumped manually. I started by building a small external compressor, but I really wanted it to be housed inside the model. There is very little available space so it had to be sandwiched under the tower. I was able to make it fit and it works great. Now I am left with the question of whether or not to include this compressor in the instructions. It is certainly NOT Akiyuki and furthermore it is rather crude because I have no talent. On the other hand, anyone can simply elect not to build that part. Thoughts?

A planetary gearset has been on the top of my wishlist for Technic functionality for a long time. You've done a great job and made a really compelling video. Personally, I'd like to see an epicyclic set that is a bit more generic and not just limited to a wheel hub. For maximum educational possibilities, you should be able drive the sun, the planet carrier, or the ring gear and likewise use any of the three for output. This really shows how just changing which portion is fixed can totally change the gear ratios. I also think it would cool to be able to use planet and sun gears which are not all the same size. I'd be very happy if your design were to appear in a set. In my opinion, the thing that makes this least likely is the rolling element bearings. While these would be fantastic for minimal friction and structural strength, they would presumably need to be metal. Apart from the cost, they are probably too dangerous as a swallowing hazard for kids. I suppose they could technically be plastic and have lower load capability but more safety.

The elevator would be awesome, but in the short term I was hoping to feed the marble run with the bucket wheel tower. I did a quick computer image for sizing, and it looks like the tower is too short. I may have to add two more levels of buckets like Akiyuki did in his most recent videos. Edit: Problem solved! With another course of buckets it lines up very well. This is an easy mod to make.

You're not kidding! I think that's the largest LDraw file I have ever seen. We'll see how well LPub can handle it for making instructions. Wow, that's a lot of yellow! I like the unique look of it.

I just built a display case for it with a wooden base like my other modules.

Thanks ReBricker. Once you do that I'll add a link to the timing video within the instructions. I typically call it the bucket factory to more easily distinguish it from the other modules. They are all ball factories, after a fashion. One mod I would like to add to this module is the 21st bucket. It was discovered late in the process that Akiyuki actually uses 21 buckets instead of 20 but only if the 2nd conveyor goes slower than the first. This would make precise timing of the bucket shifter less critical. The mod is quite simple; some gears just need to be swapped in one of the gearbox brackets.

Please use a more descriptive title for your topic. "Lego Technic" doesn't really tell anyone what your topic is about. Set 5590 is not a Technic set, it is Model Team set. In any case, Bricklink is always the best place to look. It looks like 33 copies of this set are currently for sale. You are going to pay a huge premium for a sealed set. Personally, I have had very good luck buying used from Bricklink. On the other hand, don't buy used from eBay since there are too many bad sellers. In general, buying and selling questions should go in the "Buying and Selling" subforum of Eurobricks. You will get better general advice there. Good luck!

Has anyone actually built the pneumatic module yet? I have been working on the instructions and I am a bit concerned about it structurally. There are no studded rails like the normal modules, instead there is a just a single studless level at the bottom. I'm worried that it will be too flimsy to transport. I'll be building it next week to find out for certain. I've also created some draft PDF instructions for the bucket factory. Anyone willing to test them? Please volunteer only if you are serious about building this model in the near term.

An airbrush compressor would certainly work better, but aquarium compressors are super cheap. The only question would be whether they provide enough airflow and pressure.

Note that you also simply turn off notifications in Bricklink preferences. This is what I have done.

The original marble run consisted of about 4 levels and was black, turquoise, and yellow and was used as an output for his elevator module. Later versions were much bigger and had more like 6 levels and included blue tubing. For example, in this video you can see it as an output to the bucket wheel tower. However, it also looks like he is currently using a much taller bucket wheel tower than we have produced instructions for (instructions have 6 buckets, Akiyuki currently has 8). Can you give me height of your input in LDU so I can see if it lines up with the output of the tower? I am going to try using commercial 3mm pneumatic tubing from McMaster Carr. It comes in many colors.

Did you base your model on Akiyuki's original design or one of his later videos? This module seems to have changed and grown a lot over the years. This is going to lead to an challenging Bricklink problem. Since the rigid tubing is listed as separate part numbers at each length, how can you search for which seller has the most quantity across a variety of lengths? I'm going to need a lot of it and it is often hard to find. Is this the only module which is totally passive with no motor? I think it might be.

Yes, I found exactly the same thing. Sometimes it only picks up 4 balls and drops the 5th. I found this could be improved by prying apart the axles on the sides of the "bucket". This gives a little more room inside and it works better.

Who built the bucket factory you had in use and how was its reliability? I found that mine is not really reliable enough to use in a GBC circuit. In particular, the bucket shifter tends to get jammed and starts dropping buckets. As I understand it from the ReBricker, one of the things Akiyuki asked for before people started doing instructions of his models was that he always be credited if they are displayed at shows. We need to be careful to honor his wishes on this. That sounds tremendously useful! I could use one of those.

I finished building this module last weekend and I have to say that I love it. Super reliable and fun to watch. I particularly like all the unusual angles used in the red support structure which were not strictly necessary but add to the visual interest of the model.

The criteria of "if it is on Blakbird's shelf then it should be in the HOF" was just a joke. Obviously I think highly of every MOC I decide to build, but I am not the sole arbiter of HOF. If you are referring to Grazi's tow truck (my first instructions), I agree that this one of the best MOCs ever but he is not a EB member. If you just want to know which models I have built and/or made instructions for, there are other threads for that!

Amazing layout! I'm so happy to see those Akiyuki instructions going to good use.

That looks pretty simple! Any interest in adding it to your file? Edit: It is mechanically simple, but it requires substantial modifications to the existing module to add the 1 stud space between the input hopper and the lift. I also think that this module needs an output ramp of some sort. Right now it just lifts the balls up and drops them off the top. That same video shows a zig-zag output ramp that I think would be good to add.

Oddly, even though I've purchased and used hundreds of motors of different types I've never had any of them fail.

Yes, you have to uses the old tracks. Not only are the turntables used as sprockets, they are also driven directly by 8 tooth gears. There would be no way to drive the new sprockets without a complete redesign.