doug72

(WIP/MOC) - Dockside Level Luffing Crane My latest project is to build a Lego replica of a Meccano Super model of a Stothert & Pitt level Luffing Dockside crane which has two unusual features. The hoisting hook is maintained at a constant height when the jib is raised or lowered (luffing) by means of the “Toplis” system. Luffing the jib is NOT done using ropes and pulleys, instead this is done using a crank and a connecting beam to the jib. This type of crane was able to raise and lower the jib very quickly without fear of over luffing. Stothert & Pitt Dockside Crane dockcrane by Doug Ridgway, Meccano super model LLDS-crane by Doug Ridgway, on Flickr “Toplis" Level Luffing system explained here: toplislevelluffing by Doug Ridgway, on Flickr Progress to date:_ Traveling Gantry has a track gauge of 15L, the same as my giant Block Setting Crane. Basic unit built but further improvements are planned. Each gantry leg has two track wheels - wheels are only driven on two legs of the gantry (one on each track rail) which sufficient to move the crane along the track. The wheels are driven by a vertically mounted M motor through the turntable via 3 right angle 1:1 units then to a 8:1 worm drive down each gantry leg with a final 12/20 reduction giving an overall reduction of 13.3:1 for the driven track wheels. re missing wheels:- Waiting on a delivery from Lego for wheels rim narrow 18 X 7 with cross hole (56903) to complete this. IMG_2720 by Doug Ridgway, on Flickr Turntable unit: - This forms the base of the crane machinery house and contains three M motors and their gear boxes, each built as a separate unit & mounted on to the turntable along with a battery box doubling as a counterweight. Space is very tight requiring some innovative but legal construction to ensure everything was well braced. The hoist drum & drive will be located in the tower for the level level luffing system. IMG_2721 by Doug Ridgway, on Flickr Next task will be to figure out the correct geometry to get the Toplis Level luffing of the hook working correctly and the crank arm linkage for raising and lowering the jib. A plain hook will be on the hoist rope and later possible a working grab.

Sold Out !

Try Brickowl.com. I got the new grab buckets and new actuators that way ok.

Improvements can now be revealed that were carried out after the contest entry & voting closed. 1/. Tower re-designed to allow all three drives to pass up inside the tower and stop tendency of the tower to twist when slewing. 2/. Base unit & motors layout modified to allow for new drive arrangement. 3/. Universal couplings eliminated 4/. Lego legal counterweight replace by a neater housing containing a block of steel. New base and drive shafts arrangement. IMG_2717 by Doug Ridgway, on Flickr Top of tower showing new counterweight and slewing reduction gearbox. IMG_2718 by Doug Ridgway, on Flickr

Well done to everyone that took part in this contest - some realy great ideas and designs. Has re-kindled my interest in building cranes, this time in Lego not Meccano.

Many thanks for that solution - means a re-design for the connection between the top of the tower & the Z60 turntable

A part to allow an 8T gear to mesh with the new Z60 turntable plus another to allow a worm gear to be used would be great. Had many problems getting a satisfactry solution for my TC8 crane entry.

Try a 12T double bevel gear on the red and blue axles and a 36Tdouble bevel gear on the centre hole. That should fit within your space limits. An 8T/40T/8T gearing might also fit.

These two monster under sea mining machines have just been completed by a company on the Tyne in NE England. Ideal Lego creations ! The man could be minifig scale ! Under Sea Mining machine Cutter arm moves up & down and left to right undersea-1 by Doug Ridgway, on Flickr Bulk cutter undersea-2 by Doug Ridgway, on Flickr

Improvements to Tower Crane: Both this tower crane and the TC8 contest entry tower crane had the three drives running up the outside of the tower something I was not really happy with. I have now modified the horizontal jib tower crane so that the three drives are contained inside the tower. The structure of the tower had to be re-designed to allow the drives to pass through and this has had the added advantage of making the tower more rigid with less tendency to twisting when slewing the jib. This meant the three motors had to be re-positioned on the base unit along with their right angle drives. Hoisting & traversing drives pass up through the turntable. The slewing drive requires a short universal joint section to the reduction gearbox again contained within the tower. Drive for slewing is via a compact 64:1 reduction gearbox then an 8T gear driving the Z56 turntable giving an overall ratio of 448:1 If 1L worms gears were available an even more compact double reduction gear box could be built. Base unit showing the three M drive motors, right angle drives and the drive shafts. IMG_2714 by Doug Ridgway, on Flickr Side view showing slewing reduction gear box. IMG_2715 by Doug Ridgway, on Flickr Next step is to modify the Luffing Jib Tower Crane.

Klien K500 water bouser with Cat tractor unit. Allows for other MOC builds using alternative articulated section such as dump body etc. Plenty of body panels. IMG_2712 by Doug Ridgway, on Flickr

Lots of diverse cranes with some ingenious solutions. I judged on looks, functions and smoothness of operation. 5:10 6:6 15:4 9:3 4:2 12:1 Good luck to all the entries.

Unable to open your entry video. Correction - won't open on my iPad mini but works ok on main Mac computer. Nice video. Doug

My work space & study. parts sorted into recycled ice cream containers & storage trays. IMG_2706 by Doug Ridgway, on Flickr IMG_2710 by Doug Ridgway, on Flickr

Last minute improvements Improved two stage worm gear reduction unit now built and installed giving a 64;1 ratio at the top of the tower for slewing drive. Overall reduction for slewing is 320:1 but will be reduced to either 160:1 or 192:1 by gearing at L motor output axle. Front view of 64:1 gear reduction unit. IMG_2704 by Doug Ridgway, on Flickr Rear view IMG_2705 by Doug Ridgway, on Flickr

New contest entry video showing improved slewing in action. MVI_2703 by Doug Ridgway, on Flickr

As a hoist rope on any type of crane comes out at the head of a boom and then attached to the lifting hook, can't see how this can be done as both boom heads are connected to the turntable unit, thus making it impossible to actually lift anything.

Tried that but a thin 12T bevel gear only engages with the bevel part of the Z60 turntable gear ring and has very poor meshing. What is needed is a 12T parallel gear with same profile as the latest 8T gear. With a thinned down gear works fine. Note: only for testing - contest entry uses a standard 12T double bevel gear - just have to ensure that the rotating part is balanced so the bottom of the 5 x 7 frame is level and not tilted one way or the other.

Slewing problem is due to intermittent contact between the 12T double bevel gear and the bottom edge of the corners on the 5 x 7 frame on which the top structure is built on. The 12T double bevel gear is 1L thick same as the turntable gear ring, see close up image. New drive unit for slewing the crane now designed, installed and rotation is now much smoother. Upper unit has a 8:1 worm gear reduction with a 1:1 right angle drive up to the 12T slewing gear. Installing this onto the side of the tower was a challange. Lower unit has a 8:1 worm gear reduction then a step up stage 20:12 gears. Overall gear ratio - 8 x 8 x 5 x 20/12 = 192:1 Side view showing new transmission for slewing:- IMG_2701 by Doug Ridgway, on Flickr Close up view showing contact point between 12T double bevel gear and corner of the 5 x 7 frame:- IMG_2698 by Doug Ridgway, on Flickr Upper reduction worm gear unit and right angle drive:- (8:1) IMG_2699 by Doug Ridgway, on Flickr Lower worm gear reduction and step up gears: (4.8:1) IMG_2700 by Doug Ridgway, on Flickr Hopefully I will have time to remake to the entry contest video.

Nice piece of outdoor sculpture and smooth rotation but does it actually lift or hoist the two cranes ?

Jim, Thanks for the help - after a couple of tries now sorted and video visble on my entry page. Just need to sort out slewing issue and post a updated video. Thanks

Re Entry Video I normally use Flika but for some reason won't allow me to show more than the first 2m 30s with the rest cut. Made a video using YouTube and posted the link in my entry posting but how do you embed it so it shows on the page i.e. image.

Re Slewing being jerky: Now concluded that this is being caused by the long drive shaft up the side of the tower - 64L to universla joints. The axles are acting as a torsion spring (twisting) and building up force then releasing it, resulting in jerky rotaion. Have tested this therory by making a temporary worm reduction unit at top of tower just below the slewing drive gear and then using a M motor coupled directly to it the slewing motion is now steady and smooth. Now have to re-design the drive so that all the gear reduction is done near the top of the tower. Probably will be a 2 stage worm drive giving 64:1 ratio.

It was a Christmas gift to my eldest grandson many years ago - who no longer uses it - so it was returned for me to use. Needs adaptor leads to control PF motors and works OK. re Entry video" I need to upload this again to Flika as the last appears not to upload OK video's longer than 2m 30s.

2. TEREX LUFFING JIB TOWER CRANE This model I will be submitting for the contest was inspired by a crane of this type currently at work near where I live on a regeneration project. Terex C180-16 Luffing Jib Tower Crane on site. by Doug Ridgway, on Flickr The crane being used is a Terex CTL180-16 with a load capacity of 16 tons and is operated by Bower & Kirkland. The Lego model crane is operated by LW Lifting Service. This is my first attempt at a large Lego MOC. Functions:- Three L motors operate: 1/. Slewing of the crane with 200:1 reduction 2/. Luffing of the jib between near vertical to horizontal with 40:1 reduction for the hoist drum and with 5:1 rope pulley system to the jib.. 3/. Hoisting with 8:1 reduction. Height of tower = 60 Cm. Height with jib fully raised = 102 Cm. Length of jib = 50 Cm Control / Power Supply Unit: The crane is operated using a 9573 Technic Control Centre by using PF 8” extension / adaptor leads. This can be operated manually or two programs can set up to perform an automatic sequence of movements. Crane base with a cluster of three L motors and their individual right angle drives up the tower. IMG_2675 by Doug Ridgway, on Flickr Winding House, operators cabin and counterweight. Contains the two coaxial drives from the turntable and the right angle drives to the two rope drums, for hoisting and luffing. IMG_2676 by Doug Ridgway, on Flickr View from Counterweight end. IMG_2695 by Doug Ridgway, on Flickr Jib fully raised: IMG_2670 by Doug Ridgway, on Flickr Jib lowered to horizontal: IMG_2671 by Doug Ridgway, on Flickr New Video showing crane in operation with improved slewing system. MVI_2703 by Doug Ridgway, on Flickr Video: YouTube version [m.e.d.i.a.] [/m.e.d.i.a.]Gear reduction for slewing now at top of tower with a compact 64:1 using two stage worm gears meshing with 8T gears making for a more compact and neater unit. Front view of 64:1 gear reduction unit. IMG_2704 by Doug Ridgway, on Flickr Rear view IMG_2705 by Doug Ridgway, on Flickr The build and the discussion about this model can be found here Doug72