doug72

This hoist control method might be workable, slow start / stop - fast in between and upper & lower limits easy to set.

I suspect worm gears but cannot see if it is.

Probably each XL motor drives one track via a right angle gearing, so you can be able to run each track at different speeds to steer the vehicle. Not the best solution, a subtractor steering set up is much easier to steer using a train PF controller.

Worth a try, the larger 56t gear driven by the 8T gear has more turning force. At least you have proved the timing works OK and track lines up. Even on mine using the 56T turntable the rotation slows down a bit as the spring compresses. The last mod has got the distance between fixed and rotating gear rings constant all round.

A Whitworth Quick return mechanism might work if hidden under base and connected to the drop section by cords. Has a slow motion at each end of stroke with a fast travel in between. see this video.

Thanks for the photo, The Z28 mod fits in very well. Hope the timing works OK. Now modified the connection between the ball discharge chute and yellow gear rings. Now a much more rigid connection & no flexing. Tested and OK. Parts required:- 2 x blue axle pin connectors . 2 x 4L thin beam with axle holes each end (Red) 2 x 3L axle

Looks good and there is good clearance of the Z28 t/t from the yellow gear rings. Can you post a pic of the 24T / 8T reduction gear side.

That was quick ! Fitting the Z28 MOD will be a tight fit, I,ve not actually done it and keeped the Z56 version. Look forward to see your solution and how it performs. The top connection between ball discharge chute and the gear ring at the entry from the elevator is a bit flimsy & relies on a single axle causing the ring to flex as the unit rotates, think I have found a way to improve it Will try it tomorrow & post the Mod.

Rotary Dumper Dougs MOD Mk 3 After a lot of head scratching, trial & error and a number of false starts, I have finally eliminated the 1/2 L problem and kept the timing gears the same. First attempt I raised the mounting points for the static gear rings by 1/2 L but was not successful. A new rotating frame had to be developed that incorporated a 0.5 thin 5L beam between the two 5 x 7 frames, to ensure all eight 20T gears ran on the curved racks smoothly.. This allowed the attachment points for the drive unit to remain the same. First test was not successful as the unit rotated the wrong way !! The black 20T gear no longer requires a 16T idler gear, instead it meshes directly with the tan 20T gears that engage with the gear rings. Simple fix - reposition the tan 12T gear to the other side of the right angle gear frame - see photo. Trip timing had to be reset correctly again. All yellow gear quadrant gears are now on the same plane and track beams now all level throughout. Rotation is also smoother. End view Side view Location where 12T bevel gear had to be repositioned to get correct rotation.

It is possible to use a Z28 turntable instead of the Z56 turntable by changing the two 16T gears (1:1) to 24T /8T gears. (3:1) This will give the required reduction. i.e. 3 x 3 x 28 / 12 = 21:1 The 12TDBG would have to be at a right angle to the turntable 28T gear so another right angle drive would be required. Use the 24T gear to get the timing right to release the train as the track lines up. Heres a mock up of possible gear layout. Its a tight squeeze to fit in place.

Good progress. A Z56 turntable must be used in order to get a 7:1 reduction to get the timing correct. i.e. 56 / 8 = 7 plus the 3:1 stage gives 21:1 reduction for correct timing This cannot be achieved using a Z60 turntable as only the 12T gear will mesh and only gives a 5:1 reduction. ======================================================================= Found another annoying issue which I have yet to solve, the dreaded 1/2 L problem ! Although the train unit enters the dumper, rotates and exists OK there is an issue in that the track within the dumper is not level & horizontal. The track at the static ring end is lower by 1/2 L when track at the exit lines up with the output track to the elevator. This can cause the 8T gear on the train axle ends to not engage with the 4L gear rack segements as train exits the dumper due to the slight hump - hence the section of 4L gear racks over lapping the rotating gear rings. This 1/2 L discrepancy is caused by the gearing arrangement in the rotation frame connecting to the trip section The distance between the black 20T gear axle and the pins joining the gear ring quadrants is 4.5L Tried rotating it 180 degs but this makes the distance 5.5L Somehow need to find if possible to get it correct at 5L A 12T double bevel gear with 18mm wedge guide wheels will work without fouling the gear ring and will be able to get the correct overall 21:1 reduction Still investigating if this can be solved with a redesign of the rotating frame but may have to put up with it. Doug

Checked through the LXF file and the photo of your build progress. Noticed you have use small wheels (rollers) with rubber tires to support the rotating yellow gear rings. My version has reverted to the original 18mm diam. wheels. Apologies for my error. Now checked my photos which were taken over a 7 min period, some show small roller others large roller !! Had me puzzled as to how this possible as there is not enough time to change them between taking photos. Now realised I had one sIde using the small roller with tire the other side using the larger 18mm diam. roller !!!! Two smaller rollers caused a step between the track beams. Correct rollers are the 18mm diam both sides with a 12T double bevel gear engaging with the curved gear rack.

Looking good,

Rotary Dumper :- My MOD update. Noticed the ball discharge hopper had a tendency to lean towards the side with the counterweight box when the train uinit was released as the track lined up. Tested without the counter-weight box and found to be OK. The train ball hopper engagement with the rotating hopper guide rails is now better aligned and with less weight the rotation of the dumper is smoother and faster.

Don't like the "Hook" I will use one of my METAL hooks, when I get the set.

I thought so - a picture says a thousand words. Now tested with a four lobe rotor for a Vee Reverser and works OK.

Thanks for your work in making these files. re blue bands: to get the correct tension one end has to be wrapped around axle twice as per photos. Re Rotary Dumper layout - now broken down into each module as Dining table needed for its intended purpose !!!! Going to see if I can close couple the elevator and rotary dumper units to shorten overall length.

Thanks for that, checked the file and one crucial part is not shown. i.e. the 2L worm gear that engages with the 24T gear that drives the trip rotor.

Thanks for the suggestion, it has possibilities - might change the title to WAKE RIDER. I was thinking of either tilting the moving belt from side to side or a 32L axle from behind to oscillate the surfer. Hopefully I will be able to control all movements using 1 or 2 motors with PF control.

It will definitly be wider, depending on many lego track links I have but only one rider as only have one lego figure. Have Meccanno figure but it has lost it feet and is banned !

(TC14) Urban Wave: (WIP) The fairground near where I live has a unique fairground ride in the UK, and I am attempting to replicate this for the contest. You can surf without getting wet ! A fairly simple build but controlling the rider will be a challenge. My grand children always go on it when they visit.

It’s on my Xmas list !

Slewing is not very smooth, as if there is an axle winding up under torsion, twisting & then releasing.

I only got into building this train system a few months ago, so no experience of V1 train unit. The V2 is reliable - I made a simple MOD to prevent the end of reverser bars from fouling when in the rotary dumper. (see earlier posts). You need to ensure the PF cables don't foul the trip bars and use the old style PF switch or MOD later version. The train wheels flanges only just touch when in the reverser or driving other modules, so there is no problem with friction band on wheels wearing down. When the train is reversed, the initial impertous to move the unit is the 8T gear on axle end acting on the 24T gear that drives the trip system, enough to get the other 8T gears to engage with the rack and move the train. The round disc with hole are guides on the axles to keep the train in alignment with the gear racks etc. Re Unloader / Loader: As I didn't have enough shock absorbers I used counterweights instead - see images in an earlier post. Best of luck with the Rotary Dumper / Elevator, I had a very frustrating time trying to get the Akiyuki Dumper version working and gave up - hence my MOD. Doug72

As requested: Trip unit shortened by 2L with standard two lobe trip rotor. The two slide bars are yellow 7L axles. Four lobe rotor if used to operate a track switch. The red LEGO Technic Cross Block 1 x 3 (Axle/Pin/Pin) (42003) is used for the trip & the anchor point for the trip trigger arm. IMG_5902 IMG_5900 IMG_5904