doug72

Note: The white 24T clutch gear that can be seen rotating - in the video - as trolley traverses is not really necessary as the over travel is protected by other means.

Here's the video - best without sound !! MVI_2607 by Doug Ridgway, on Flickr Only one problem is tower twists slightly when slewing the jib arm - can't find a way to brace it to stop this - any ideas. Doug72

Only just finished it - I will post a video later. All three movements possible at the same time: Slewing, Hoisting, Traversing trolley. I,m on the verge of dismantling my ultimate 42009 mobile crane in order to build more static cranes. Releases 8 PF motors / 4 PF Rx and loads of parts. On the lookout for metal crane hooks - on my Xmas list !!

Follwing the succesful build of a horizontal jib - I set out to build the rest of this tower crane. Tower is Red as thats the most parts I had in one coulour to build it - jib yellow for same reason. Took four re-builds to get the Z60 turntable, winding drums and drives to them to work smoothly. All fitted into a 5 x 7 x 11L space on top of the turntable. Hoist trolley travel took a lot of time to devise and get to work smoothly. - had to resort to studded technic beams with flat plates for wheels to run along. The traversing system uses only a single "special" rope. Counterweight consist of an empty 88000 battery box filled with a heavy lead weight - hence not entered into contest. IMG_2606 by Doug Ridgway, on Flickr

I have made a mock up of the other side minus the Z60 turntable showing the rear view of the spacings required to get double bevel gears to mesh with the Z60 turntable. The Red and Green pins would connect to the lower part of the turntable. IMG_2604 by Doug Ridgway, on Flickr

Unfortunately not as the two Z60 turntables I have are now built into my TC8 luffing jib tower crane and the alternative horizontal tower crane jib I am working on now.

With smaller scale models its quite a challange to fit everything in without touching other rotating parts and at the same time ensuring its all shafts and gears are braced securely. I.ve had to devise some inovative solutions still keeping it Lego Legal.

Currently building an alternative horizontal jib for use on my TC8 tower crane entry after the contest is over by using that base & tower to mount the alternative jib. Design of jib done completed after two attempts and approximates to a triangular cross section. A hoist trolley traversing system was devised using a single rope system. Found that using studless beams for the trolley to run on causes wheels to drop as they passed over joints between the 15L sections - now replace by studded Technic 16L beams with 8x1L plates on top edge for the wheels with rubber tires to run on. Winding drum house: 1st attempt used a design based on the TC8 design but did not look right and did not allow hoist trolley to get in close to the tower. Then a "Eurecka" moment relaxing in a hot bath ! Turn the winding house so that it is vertical. Next step design / build the tower top, jib support tie rods and the counterweight jib. This time the counterweight box will be filled with lead !

At the scale of my build it could only be dummy representation. I decided not to include it as the crane I have based mine on was erected by a huge mobile crane so no climbing frame was required. The building being constructed is only four stories high on constricted site and the crane doesn't need to get any taller.

My crane - with heightened tower at 72L - is now finished and has a load hanging on the hook. Now comes the hard part making a video ! Will have to re-arrange the shelving in my study to display the finished crane which stands 1.2m high Now designing an alternative top section for conversion to a fixed horizontal jib tower crane that can be mounted on the existing tower section. Jib built OK and come up with a solution to move the hoist trolly will along the beam, without the use of double drums. New drum house unit has to be built. This will not be part of my contest entry.

A good way to connect 15L beams is to use the LEGO Beam I Frame (3 x 5L) ( p/n. 14720) with two pins in one 15L beam and 1 pin in the other as long as you cross brace the structure well . I have used this for my tower crane for the jib construction. IMG_2581 by Doug Ridgway, on Flickr

Luffing Jib: 1st jib:- This was based on the crawler carne jib of 7 x 7 x cross section and rather skeletal. See jib on prototype test crane. 2nd jib:- 5 x 7 cross section with diagonals better located but still too wide. IMG_2571 by Doug Ridgway, on Flickr 3rd jib:- 5 X 5 x 72L with double diagonal bracing more like the real crane jib. This jib design also has potential for use for a horizontal tower crane jib. An angle of jib indicator is also fitted. I wish there were longer thin lift arms, it would make the jib lighter ! IMG_2583 by Doug Ridgway, on Flickr The Hook:- I have used a Lego metal hook but had to requisition it from a previous model ! They are not available from Lego and very expensive on eBay

Drum unit house. The drum house top supports the Frame for the jib luffing rope system. A cabin with minifig crane operator along with side panels were added. Counterweights: To conform with the contest rules I used a Lego 88000 battery box with 6 AAA batteries plus a Lego 2 x 2 x 6 train weight mounted on a 6 x 8 studded plate that can be adjusted manually to counter balance the jib. IMG_2581 by Doug Ridgway, on Flickr

Luffing & Hoist rope drums. It was quite a challenge to fit these into 15L x 9L x 5L drum house attached to the turntable top. From the turntable the two coaxial vertical drive shafts connect to two right angle drives to the rope drums for luffing and hoisting rope drums. This are 3L apart but the two drive shafts to the worm gears needed to be 5L apart. This was achieved by additional reduction gear meshing directly with the 12T gear in the centre right angle drive to the luffing drum. This saved 3L and solved clearance issues with the drums. The rope drums are are mounted one above the other. Luffing drum has 24T clutch gear on the drum shaft. Hoisting has 8T idler gear and 8T gear on drum shaft. Drums are constructed using wedge pulleys and 2 x 2 round studded plates. Some problems arose because studded technic is not wholly compatible with studless technic resulting in width issues. Finally found a use for 14T thin bevel gears (used in old differential unit) as spacers to keep the wedge pulley drum ends rubbing on the worm gears. Photos shows the drum unit before installing on top of the crane tower. IMG_2564 by Doug Ridgway, on Flickr IMG_2568 by Doug Ridgway, on Flickr IMG_2565 by Doug Ridgway, on Flickr IMG_2566 by Doug Ridgway, on Flickr IMG_2567 by Doug Ridgway, on Flickr IMG_2568 by Doug Ridgway, on Flickr

Thanks for the suggestion. Now modified the gearing for slewing the turntable using a 12T double bevel gear (grey) on a horizontal axis meshing with the turntable 60T gear ring and a 12T double bevel gear (black) on vertical axis which is on the vertical shafting down the tower. It fits OK within the same tower framework. Just had to replace two 5L beams with 7L beams and extra horizontal beam to provide strong bracing of the vertical axis gear, shafting & universal couplings were altered to suit. It also eliminates the problem of the previous set up where the 12T gear was catching on the underside of the superstructure as it rotated. IMG_2580 by Doug Ridgway, on Flickr

Its a LEGO Technic Connector Block 3 x 3 Triangular with Crossaxle (32175) I have added to it a grey Angle connector #1 to the axle part to give extra support for te jib pivots.

Just tried it and : NO it does not mesh with a Z60 gear ring - see photo. At 1L spacing existing worm meshes OK with a Z56 gear ring BUT NOT with a Z60 gear - note the bent axle. The worm with the red bushes show it does not line up with holes in the 7 x 5 grey frame - again about 1/2L out. So Lego needs to design a new larger diam, worm gear to mesh with the Z60 turntable at 2L spacing. IMG_2579 by Doug Ridgway, on Flickr This contest has resurrected my boyhood passion for building cranes using Meccanno. Have several indeas for future cranes to build.

Drive to the Turntable Unit: The prototype test model used a Z56 turntable but this was stiff and crane wobbled when slewing. The drive running up the side of the tower to a 8T gear meshed directly with the 56T gear ring. Once the new Z60 turntable received this was used and found it is much smoother and steadier when slewing. However it appears that only double bevel gears, 12T, 20T, 36T mesh OK BUT when using the 12T gear it will not mesh in the conventional location without use of a thin spacer 3L plate. This was not successful as the 12T gear jumped out of mesh if too much load. Finial solution was to offset the 12T gear by 3Lx 2L with a beam to stop it disengaging. See my previous post #7 with gear 3 showing lposition of 12T gear on the Z60 ring gear. http://www.eurobrick...howtopic=114560 This meant the drive up the side of the tower had to be offset & two 3L universal couplings required. Then found axle required between them had to be 11L which is not made by Lego (missing from the grey axle sequence) Solution two 5.5 axles with stop, back to back with a connecting sleeve. IMG_2577 by Doug Ridgway, on Flickr

Milan, The finished crane has a four unit high tower, the photo on the opening page shows the test model I built to iron out any bugs before building the final version. The completed crane is 50 Cm from Base to turntable level. To top of jib is 108 Cm above base when luffed fully in. It was much easier working sitting down at my work station than standing up - extra tower sections added later. The completed model currently resides on our dining table with permission from my wife !!

Milan, On the real crane the tower cross section is square right down to ground level where it is bolted down to heavy concrete foundations. Hence the bracing of the bottom section of my tower. At the moment the tower is four 15L units high, could add more sections and go higher but then problems storing and displaying it and enough parts (beams & long axles) to do that. By using the diagonal struts I can display it on any flat surface and they are enough to prevent toppling. See Terex drawing showin side elevation. terex-elevation by Doug Ridgway, on Flickr

I have had no problems with the tower falling over due to sufficient "legal" Lego counterweighting. The base could be widened or as in real life fixed onto a foundation block. In realy tall tower cranes they are often braced by cables or tied into the side of the building. I am also not going to attempt any lifting records rather demonstrate operation how it operates. With jib fully luffed in and hook at min. radius it can lift two "C" batteries OK. As the jib is luffed out the load capacity reduces just as in real life.

The Tower First tower constructed the same way as the jib on the 42042 Crawer Crane but was not satisfactory, being too flimsy and very skeletal looking. New tower designed which is more authentic looking and stronger. The tower is 7L x 7L x 61L high. The drive shaft and 12T gear for slewing have to be offset for reasons explained later. IMG_2573 by Doug Ridgway, on Flickr Tower Top - transfer gears. At top of the tower the shaft drives for luffing and hoisting have to connect into the centre before passing up through the turntable co-axially. IMG_2575 by Doug Ridgway, on Flickr

The crane I will be submitting is based on a Terex CTL-180-16 currently at work on a building project near where I live. The crane has a 16 ton lifting capacity. IMG_2522 by Doug Ridgway, on Flickr A prototype model was built to find out if my ideas would work, determine stability and the amount of counterweight required. This was built from parts available using the Z56 turntable. More parts ordered including the new Z60 turntable, 15L beams and many 2Lwith axle pins. Building commenced. The prototype test model: Built using jib design from the 42042 crawler crane for the tower and jib sections. Only one section of tower built as its easier to work on. The final model will have more tower sections which are re-designed to be more uniform and the jib made slender. Control for testing during construction done by a bank of PF switches and a AAA battery box. Control of final model will be using the Lego Technic Control Centre which can be programmed to perform a sequence of movements automatically. Functions: 3 PF motors: M motor for slewing jib and winding house / M motor for hook hoisting / L motor for luffing the jib. Final model has a height of 108 cm when jib fully raised. Outreach with jib horizontal is 58 Cm. Contol by PF swiches or by using the Lego Technic Control Centre. IMG_2523 by Doug Ridgway, on Flickr Tower base: The base is free standing and consists of a cruxiform arrangment of grey beams which support the tower. Three PF motors are arranged on one leg with right angle drives for the shafting that runs up the side of the tower to the top of the crane. a. Slewing: M motor driving via a worm gear meshing with a 24T clutch gear then a further 1.66:1 reduction. b. Luffing : L motor via a 1:1 right angle drive. c. Hoisting: M motor via a1:1 right angle drive. IMG_2552 by Doug Ridgway, on Flickr

What happened to the 2 week rule ?

Milan, This is my first entry into a EuroBricks contest and I have a couple of queries. Is it allowable to change the models Title Line when posting on the Entry Topic section or do i have to stick with the one already posted ? Can you please explain "link to discussion topic" Thanks.