hpil

Just wow!

Is the quest over? https://www.lego.com/en-gb/product/tractor-60287 What size are the rear tyres on this?

How would they look on @eric trax's various tractors?

Very nice. Verrryyyy nice indeed! Well done!

Very, very nice! I particularly like the way you've got the bonnet and nose so simply - very envious! My (humble) suggestions would be to lift the cab roof another stud, extend the exhaust pipe to match and use some green 1x tiles to hide the pin holes on the cab roof.

Love it, absolutely love it! I remember trying to make a plough for 851 out of 2x1 bricks and 2x2 plates many years ago, and concluded a realistic mould board shape was not possible.... but this is just blowing my mind. Its brilliant!

After some inspiration and ideas from the likes of @TeamThrifty, @I_Igor, @nerdsforprez, @kennywest and many others, and several hundred hours sat on the living room floor, i have functioning skid unit for my 1:12 MF 6716S tractor. The real thing: http://www.masseyferguson.co.uk/mf6700s.aspx#360 Disclaimers: it uses third party tyres - 2.2" RC4WD mud basher tractor tyres - and there's still a way to go on sorting cables, pipes, detailing etc but the functions i wanted to replicate are all... functioning DSC_1185 Functions: Full 4wd - no diff locks (no space!) from an XL motor which also drives the fake engine. From the rear diff the drive is split to two half-shafts on each side, driving z18s that engage inside the power miners wheels. This keeps the speed up and so torque down, and shares the torque going to the big rear wheels, as well as making a strong & balanced structure that (hopefully) can't pull itself apart under the torque. Steering via an M motor & z24 friction clutch "Quadlink" suspended front axle using 4 rubber figure of 8 donuts as the front mounts and two small pneumatic pistons as the springs Working rear linkage & pto, plus working front linkage and pto Working UK style automatic pick-up hitch - for those not 'in the know' this is standard fitment on most UK tractors and is basically a towbar that can be lowered and lifted with the rear link arms to attach trailers, and then locked into the raised position for safe towing or when not in use. The safety latch is operated from the cab. Mounting position behind the fake engine for (future!) fitting a loader. Driven axles provide rotation to drive large LAs for the lift/lower and small LAs for the tip/crowd functions Pneumatic system (incl tank) to provide pressure for the suspended front linkage, driving pneumatics on attachments (rear and hopefully on the loader) and for 'in-cab' operation of one of the changeover catches. An L motor drives either the rear linkage or the loader lift/lower via a changeover catch (catch 1). The front linkage can be latched either to the rear linkage or to the loader drive via a second changeover (catch 2). This means the front linkage can either work simultaneously with the rear or, if there is no loader fitted, on its own. Putting catch 2 in neutral means the front linkage doesn't operate at all - for loader work. An M motor drives either the rear PTO or the loader tip/crowd via changeover catch 3. The front pto can be connected, via changeover catch 4, either to the rear pto or to the loader tip/crowd. This means the front PTO can work simultaneously with the rear or on its own if no loader is fitted. Putting catch 4 in neutral means the front pto will not work at all - for loader work. The changeover movements for catches 1 and 3 will be slaved and (hopefully) driven by a small pneumatic piston with valve lever in the cab - so this lever will control switching drive from the L & M motors between the rear linkage / pto and the loader. Movements for 2 and 4 will be manual. The M motor also drives the pnuematic pump via a z24 friction clutch and changeover catch 5. The combination of on/off via the catch 5, friction clutch and air tank should hopefully give a full range of flexibility for keeping the air tank topped up without wearing out the friction clutch. The plan is to use an SBrick to control everything, probably with two profiles - a 'loader' profile with joysticks to control drive & steering and the loader, and a 'field work' profile with joystick for drive & steering, sprung slider for linkage operation and latched slider for pto operation (if indeed such arrangement of sliders is possible - a future problem!) It could also be done with 2nr IR receivers and maybe a bit of mechanical jiggery-pokery to latch the PTO control on when required. Some more pictures: DSC_1188 DSC_1190 DSC_1202 DSC_1203 DSC_1191 DSC_1192 DSC_1193 DSC_1194 DSC_1196 Oh, and this is the first time i've tried anything on this scale and complexity - my only previous moc experience of any note was a power harrow for the 8284 tractor... this Massey has made my head hurt!

more photos - showing the bonnet vs the template. IMG_7339 IMG_7338

Its the perspective - will post some more photos shortly, once flickr gets back up and running properly!

Some glacial progress waiting for parts, but beginning to get there. Some photos from a while back showing the internals plus the current state of WIP... clutches for loader / linkage drive. yellow axle connectors take drive to fake engine. Back end. yellow z20s mesh to grey z16s in previous photo. Transverse clutch is the drive to the pneumatic pump. Centre red axle takes drive to fake engine. rear linkage module and rear axle module underside of the back end, showing the release mechanism for the automatic pick-up hitch and finally, where its at at the moment...

a bit of progress - having to build up the outside bits in many colours, including raiding the kid's collection when they are in bed, so i can get the design sorted and then create a list parts, colours and quantities for the next parts order. The bonnet is a quick fudge but doesn't look quite right, so think i might take some inspiration from @eric trax and use system to get nicer looking shapes. Still a lot to do on the inside of the cab - i kind of got stalled so went on to the cab roof, which led to putting it in place to see how it looked... and a comparison against 42030 from earlier in the build

Instructions bought That is a real shame - its a great model. Anything that can be done to change your mind...?

Oooohhhh, that is stunning! Well done for getting so much in to a small space.

Depends on how realistic you want it. For best realism, a 4 bar linkage small Las arranged off vertical with the driven end at the bottom, pushing up on a link which in lifts the arms up and down, but this would only give you 3L for the support frame and pto since the mini LAs are each 3L wide. @TeamThrifty's Claas Axion is a nice example but too wide for for your needs. You could use mini LAs directly between the structure and lift arms, at a 45 degree angle and the driven end at the top - like a tractor front linkage. @I_Igor's Fastrac has this, only 7L wide with motors further back in the chassis. Page 10 of this thread should give you some ideas: Your best bet for realism might be @kennywest's mf1250 - that is 9L wide and uses a worm gear to dive a linkage, but a mini LA could also do the same job, possibly more compact.

Thanks. Hopefully I can incorporate some support for the gearing for the loader drive when I build up the cab & steering column. The z24 friction clutch & z8 drive pair don't have support on their outer sides, but adding a beam in would rub against the rear tyre.

Not quite what I'm looking for, but thanks. Think I've now got a solution by separating out the pump, friction clutch and changeover catch and squeezing them into different parts of the model. In the process I discovered a li ear friction clutch doesn't have enough friction to turn the pump, so had to use a z24 friction clutch

Looking for ideas for a compact pneumatic pump module that includes a friction clutch (linear or z24) and and on/off drive connection (could be changeover catch or sliding cogs). I've got an idea which is 3l x 5l x 12l, but wondering if there are any genius ideas out there...

Looks stunning @I_Igor, you've got the shape & proportions really well. Surely one for the lego ideas and for tagging jcb?

Wow, that looks stunning! Well done! Love the cab detailing, outside and in. Remind me - the motor does linkage and pto, HoG steering, and push along for the drive & engine?

42070 gets you tractor wheels plus some motors and an IR controller, plus 3L axles with stops and (I think) 5L axles with stops. 42055 I think is good value - nearly 4000 peices including some 3L and 5L axles both with stops, plus loads of 5x7 frames, long lift arms and z18 gears (with pin hole and with cross axle hole) plus 4 3L changeover catches

OOO now you're talking!! I've thought many times about trying to replicate something in lego... aaargh! what have you done to me? Woke up at 4am this morning thinking about this! However, i think i have two alternate solutions for a draft control system....

Very nice indeed - i am a sucker for tractors, and Massey ones at that, so look forwards to the finished MOC. @Erik Leppen - the three point hitch on real tractors is designed to allow the implement to sway from left to right as well as lift it up and down. The geometry of the two lower links and the top link is arranged so that lines drawn through (ie along the axis of) each link will converge at a point somewhere in the middle of the tractor. This means that when a soil engaging implement - a plough or cultivator - is working in the ground it will follow a straight line but can also deviate left and right for obstructions or as the tractor steers. If the implement were fixed to a rigid straight line, every minute adjustment to the steering would create large lateral forces and stress on the tractor linkage. This arrangement does mean that when the plough is lifted out of the ground it can freely sway from side to side, so 'check' chains, or adjustable stabiliser bars on modern tractors, are provided to limit the amount of sway. @kennywest has got the lateral movement in the lower links - other examples (that i know of) are @TeamThrifty's claas axion 960 and @BondemandClausen's NH T8.420 - plus the lower links converging to a virtual pivot point somewhere beneath the tractor. For the lateral sway to work properly you also need the same degrees of freedom on the top link (check out Team thrifty's axion), or else the top link will take all of the stress resisting the sway allowed by the lower links.... And on that tractor nerd point, don't get me started on the principles of the Ferguson draft control system...

Would a bu-wizz work for you?

So here's an off topic, ultra nerd lego meets tractor question: 851 - is it based on an mf 165 or an mf 135? Great model by the way @steph77!

Oh. Oh that looks very good, potentially just what I am after... Thanks