doug72

http://lego.brickinstructions.com/en/lego_instructions/set/7905/Building_Crane

This might be suitable or something similar its about 1m high. Something like this Terex luffing tower crane.It was my entry for the TC8 contest. The three M motors are located at the base to give lift / slew / luffing. No instructions but more can be found in the TC 8 contest from several years back.

ALL balls now showing as Out of Stock.

Multiple orders mean multple postage !!! Lego should get into GBC and make some starter kits GBC seems to be becoming a very frequent topic this days in all its forms i.e stand alone modules, GBC loops & Trains etc Perhaps its time for a seperate forum for Great Ball Contraptions. Let the debate begin !! Re balls - I have used PV Production balls and they work OK with all my GBC modules. Only thing is the high postage but you can buy in mulitples of 50 pce. PV Productions 50 orange balls = Euro 13.95 + 9.95 p&p = 0.921 card card fee = Euro 24.81 Lego balls @ £0.58 each so 50 balls plus £2.00 postage to UK = £31.00 Re 25 ball limit from Lego, two version of the orange balls so you can actually order 50 in one go.

No problem. Which motor are using in the train unit M or L - I use the L motor for the elevator & dumper as it has more power & speed. Currently doing battle with my latest module which now on Mk.5 version to get required travel from their gear racks that swing the lift arms, had a spectacular disintegration as something jammed.

Puzzling !! Something must be binding somewhere, suggest following checks, without train unit on the elevator. 1/. By hand turn the 24T gear to check if any tight spots as elevator moves. 2/. Ensure the four 12T bevel gears that engage on the racks are not too tight on the axles. 3/. Check elevator platform is level, i.e. all 12T bevel gears at same point on all four racks, I had an issue when they weren’t causing moving platform to twist. 4/. Remove the two 12T bevel gears that drive the worm gear and test if elevator platform raise & lowers OK by hand OK. 5/. Check rack sections are pressed home on the studded uprights. My elevator sometimes gives a slight jolt as the 12T bevel gear passes over the joint between the 4L gear racks. 6/. My elevator runs OK with the 20/12 bevel gears so no need to change to 16/16. 7/. Try adding some more weight into counterweight cylinders. Good luck with finding the problem.

Looks good - I see you have the 20/12 gears in place so did you find what was making it slow before, batteries or ? Rotary dumper runs smoothly - did you have to adjust the timing ? Re Video, same with me always shaky when trying to hold the camera while operating the modules.

Update: Lift & Tilt Module Crank only system found to be unsuitable and discarded. Instead devised a rack operated by a simple crank arm to get the desired range of swing. Mark1:- used an 11L rack but this was not long enough to rotate the Z60 turntable through full range and discraded. Mark 2:- used a LEGO Housing 2 x 15 x 3m F/gear Rack (18940) with a LEGO Gear Rack 14 x 2m with groove (18942) Difficult to mesh the gear rack with the Z60 turntable and unable to get desired range of movement and discarded. Mark 3:- Sucessful. Gear rack 14 x 2m used in a custom built guide housing to mesh with the Z60 T/T. A lot better arrangement and almost achieve the required swing to lift hopper off the train and swing up & over to dump. After a lot of trial & error finally almost got it right but balls sometimes did not roll out. As train car will be used in a shuttle mode balls will always dump from the same side so I have added wedge bricks inside the ball carrier to ensure balls roll out OK when at the dump position. The drive from the train reverser will be via worm gear & gear (24 or 40T) gear to rotate the two rack crank arms in a constant direction. Modified ball hopper: Next stage: build other rack unit, the support framing and connect to a train reverser unit, timing to adjust and when OK build the ball outlet collection hopper.

Don't think you can subsitute the new 28T gear for a Z28 turntable (gear half) as it has an centre axle hole. There is an axle that passes through the centre of the Z29 part which drives the robots and the two lugs are needed to mount other parts. Z28 turntable can be parted with care without damaging the part with the gear teeth, its the other half that can get damaged slightly. N.B this post would better in the GBC General discussion.

Your steering angle is probably too large. Max steering angle is approx 30 Degs with that part A universal coupling can still work up to 45 Degs. Either reduce the steering angle or use a uni coupling. Servo steering angle is 45 Degs when using a normal PF controller I.e left 45 Degs - centre - 45 Degs right only but with a train controller you can turn in 7 steps each way, with auto centre when stop button pushed, so you can do slow turns or large turns up to the limit of the flexible coupling.

Try changing the 20T & 12T gears with two 16T gears.

The setting using the 56T gear is is 1 tooth, the 16T moved 1 Tooth is the fine adjustment, equates to a 1/2 tooth on the 56T gear. The extra 4L rack was added to ensure train engaged better to leave the dumper, not really need once everything is level. re elevator:- which gears are you using before the worm gear ? See pages 11 & 12 for how the worm drive elevator evolved.

Some photos of the problem would be useful so others can view and maybe see a solution.

Akiyuki GBC Train: Lift & Tilt Unloader (WIP) Test rig built to sort out the geometry required for the lifting ball carrier off the train unit and tilt it to unload balls in a similar fashion that coal trucks unloaded the coal into coaling towers for fuelling railway steam engines. Z60 turntables are used as pivot points and the ball carrier has to rotate slightly more than 90º to ensure all balls will roll out. This can be done by two methods. 1/. auto reversing system with worm drive to the Z60 turntables or b/. A simple constantly rotating crank system to swing the lift arms and would allow Z28 turntables to be used as pivot points. Could also add LEGO Slope 75° 2 x 2 x 3 Hollow Studs, Smooth (3684 / 30499) inside the ball carrier which would ensure balls roll ot when in the 90º dump position. Train to depart once empty ball carrier back on the train. Train will ball carrier on reversing unit. Ball carrier lifted off & swung to dump position

Did you use the both adjustments when setting the timing using the 56/8 (and 16/16 gears ? See page 3 of this thread. Also guide beams in centre & sides of dumper & bridge tracks can help with de-railing problems see photo. re dining room table, I was able to use ours once a thick table cloth put ‘a on it !!!.

Yes. But some gear ratios require a 1/2 L offset to get correct meshing which can be difficult to achieve !

@Berthil Thanks for posting that. Its a bit similar to my Through Dumper module. which used a shuttle train unit which runs along 16L rail beams. Lifting the hopper on & off the train unit could use a simple sideways swing loader if can get geometry right. I will have to put my thinking cap on ! The shuttle car appears to have gear racks on the underside that engage with the series of driven 20T gears in centre of the track. To keep in the spirit of Akiyuki Train system it will need reveresers at each end to operate the loading & unloading.

20T DBG = 1.4:1 12T DBG at right angle = 2.33:1 8T spur offset =3.5:1

@Great Ball Pit The ball control gate I required will be gravity operated & rotated by the descending ball rope lift platform to transfer balls and then returned by counter weight as ball lift rises again. I am using this part to carry 15/16 balls per cycle which meet GBC ball rate OK. LEGO Slope Curved 6 x 8 x 2 Double (45411 / 56204) It is used upside down so that curved segments can be added on the underside to block excess balls in inlet hopper from entering to rotating gate untill the next transfer cycle. Found it impossible to attached curved segments to the underside of other 1/2 cylinder version. (45410) Built a test rig to check it works OK and set how many balls the rotating drum has to carry each time.

re Nylon cord for counter weights system. I find nylon cord to be very "springy" which doesn't like bends and tends to try and straighten again if not under tension. I use cord used for hanging picture frames, its about 1.5 mm dia. plaited and very flexible & strong. Also find wedge wheels have a vey shallow groove so I use the LEGO Rim Narrow Ø18 x 7 and Pin Hole with Shallow Spokes (13971 / 56902) which has a deeper groove which keeps the cord in place better.

Nice video, At the very beginning of the video there is a very brief (1 sec) view of a green rotary ball control gate. Appears to have a swing section hanging down. Do you have any details (or link) of this as I have tried without success so far to devise a rotary gate to limit the number of balls moving whist blocking any from up stream until rotary gate returned back to the loading position. Would be ideal for my rope ball lift module. Thanks for any help.

When I first joined Eurobricks forum I too was not familiar with how to upload images but following the Eurobricks guidelines I found out how to do it. ——————————————————— First upload your images onto your computer to a designated folder from your android phone, Log into Flickr and click the “cloud” symbol. (top right) Open your image folder, click image(s) you want to upload and drag and drop across to the Flickr. Click the blue box “Upload X Photo(s). Open Photostream (top left ) to view your images on Flickr. Open desired images and to get the link for embedding on Eurobricks click the share arrow (bent arrow facing right) at bottom right of the screen. Share page opens and select BBC Code Next selected image size - medium size best for general use. Either 600 x480 or 800 X 600 Max allowed on Eurobricks is 1024 x 768 Copy the the file code and paste it into your topic entry. Click save & image will appear. I find it easiest to compose any text along with the image codes on my computer first and then copy paste onto the forum. Once done you can get on with your MOC.

Thanks for the effort you have put into making the video which will be a valuable source of information. Will it include the Train GBC System ?

This part:- LEGO Change-over Catch (6641 / 19437)

Thanks. You are making good progress with this, looking forward to a video of your train GBC set up once the rotary dumper is built.