[MOC] JCB Fastrac with Rotary Rake and Tipper Trailer [Free Instructions]

[SaperPL]

The project started long before the reveal of 42136 John Deere set, but I wanted to make the front steering with custom 3D printed parts initially and I got stuck on the 3-point hitch/PTO mechanisms, so it was sitting on the hard drive for few months.

After figuring out how to make the 3-point hitch mechanism I realised I can make the virtual pivot steering and picked up the designs again around a week before the 42136 was revealed. The trailer however was clearly inspired and initially based on the trailer from the photo of 42136.

The rotary rake uses PTO at the back which is integrated into 3-point hitch, but as there is not much room to fit a clutch anymore, the rotary rake is disconnected by folding it's sides up instead of disconnecting the PTO on the tractor's side. There is also a PTO at the front underneath the bumper, but I haven't figured out an attachment for it yet.

Full gallery: https://imgur.com/a/dyCV5qL

Video featuring speed builds of each part of the set and functions showcase:

Instructions are coming, I just didn't make it with time as I didn't expect this project to grow this much with the implements.

EDIT: Instructions for the tractor are online: https://rebrickable.com/mocs/MOC-97150

EDIT2: Instructions for rotary rake are online: https://rebrickable.com/mocs/MOC-97247

EDIT3: Instructions for the tipper trailer are online: https://rebrickable.com/mocs/MOC-97357

Edited January 6, 2022 by SaperPL

[1gor]

That is cute lil Fastrac 

[Maaboo35]

Can only hope the Deere is as brilliant as this! The details are flawless. 

[Jurss]

This is great little tractor.

[proran]

This is brilliant! I always appreciate a small and clever build, and that one is a fine example of such! Very nice!

[GerritvdG]

Should be an official set, really like all the details!

Also thanks for sharing the video with the speed build, interesting!

[mpj]

This is one reason why I prefer small models than big ones. Very well done!

[Jundis]

What a great built! I hoped for a usage for the small tractor tires and you delivered :-)

[Nazgarot]

Very nice model with good functionality! I love these compact models!

I'll be trying my hand at it later.  Though I'll need to do a few mods as I lack a few parts.

_ED_

Edited December 28, 2021 by Nazgarot

[SaperPL]

Thanks guys! I'm glad you like it :)

5 hours ago, Maaboo35 said:

Can only hope the Deere is as brilliant as this! The details are flawless. 

It'd be really cool if it were like it, but it doesn't seem to be the case from what is there on the photo. I think the Lego set is going to be more robust/kid-proof

5 hours ago, GerritvdG said:

Should be an official set, really like all the details!

Thanks! I wish that was true, but we can clearly see that Lego is dumbing down those lower tier/smaller sets. My models show what you can do at this scale, but it's not what's optimal for a money making machine, so those smaller sets have less functionality, sadly.

5 hours ago, GerritvdG said:

 Also thanks for sharing the video with the speed build, interesting!

It makes sense to me to let people watch the build process if the model has some cool building techniques because not everyone is going to build with instructions. But not all models are like this and also capturing some of them is tricky with camera between my eyes and my hands.

4 hours ago, Jundis said:

What a great built! I hoped for a usage for the small tractor tires and you delivered :-)

One of the core reasons for this build was to use those :)

2 hours ago, Nazgarot said:

Very nice model with good functionality! I love these compact models!

 I'll be trying my hand at it later.  Though I'll need to do a few mods as I lack a few parts.

Check out my other models on rebrickable in the meantime, you may like some of them enough to build them if you love the compact models :)

[Brickend]

Instantly recognizable and very good looking on the wide tires!

Only comment would be that I think the rear tires should sit fully behind the cab, not slightly under it.

[SaperPL]

3 minutes ago, Brickend said:

Only comment would be that I think the rear tires should sit fully behind the cab, not slightly under it.

Yes, that is if I wanted to make it fully accurate, then the rear axle should be shifted by one stud back. I ended up with how it is placed now because of the chassis structure and that I like the feel of the ladders being right in the middle between front and rear axle. Also with that said, I usually don't put that much weight on the model being 100% accurate, rather than having a good composition and looking good.

[SaperPL]

Just noticed that it got featured on TLCB

[1gor]

1 hour ago, SaperPL said:

Just noticed that it got featured on TLCB

I have noticed it some week or so ago and wondered why there is to topic here (and there was video on YouTube)

[SaperPL]

4 minutes ago, 1gor said:

I have noticed it some week or so ago and wondered why there is to topic here (and there was video on YouTube)

I launched the video and made this photo they used on Tuesday, so it couldn't been a week ago. And the topic was already there since they have linked to it. Maybe you couldn't see it on the first page because there were more topics active at the same time.

[1gor]

4 minutes ago, SaperPL said:

I launched the video and made this photo they used on Tuesday, so it couldn't been a week ago. And the topic was already there since they have linked to it. Maybe you couldn't see it on the first page because there were more topics active at the same time.

Probably you're right, but I know that I saw it on YouTube first...since I'm building 1:18 Fastrac in (very) slow speed, I was surfing to find some idea for bonnet, since bonnets are my weakest point in tractor building...

[SaperPL]

1 minute ago, 1gor said:

Probably you're right, but I know that I saw it on YouTube first...since I'm building 1:18 Fastrac in (very) slow speed, I was surfing to find some idea for bonnet, since bonnets are my weakest point in tractor building...

It's possible - I started a thread on our local LUG forum before the video launched publicly (I linked it as unlisted video) and I have seen situations where my unlisted video was already been viewed. Seems like tags work for search on an unlisted video...

[Danifill]

Awesome model! I've built it recently - all functions work smoothly, except some minor things (the axle with a worm gear slides out a little sometimes, but it doesn't really affect anything; the sides of the bonnet aren't attached to the top part fully, so they can rotate individually in some particular places, still doesn't affect the playability that much). The exterior part is great too. Due to lack of some parts I had to change several places in the model using the parts I had.

Edit: I also have to point out that the steering system is really impressive. :D

Some photos: 

Thanks for sharing!

Edited December 31, 2021 by Danifill

[SaperPL]

On 12/31/2021 at 6:43 PM, Danifill said:

Thanks for sharing!

Thanks for building, looks good in red :D

[SaperPL]

Instructions for the tractor are online: https://rebrickable.com/mocs/MOC-97150

[SaperPL]

Instructions for the rotary rake are online: https://rebrickable.com/mocs/MOC-97247

[SaperPL]

Instructions for the tipper trailer are online: https://rebrickable.com/mocs/MOC-97357

[phmzt]

This is all brilliant!

Looking forward to building this. I especially like your idea of highly functional small scale. Keep it up 👍

[Leonardo da Bricki]

The tipper trailer mechanism is amazing. Love to see it it implemented in such a small scale, great work overall. 

[SaperPL]

9 hours ago, Leonardo da Bricki said:

The tipper trailer mechanism is amazing. Love to see it it implemented in such a small scale, great work overall. 

Thanks, but it's not ideal - in general linear actuators in lego aren't perfect for lifting the tipper bed in a way it'll work well under actual load, without some additional tricks like a knee redirecting the forces for leverage. But in such small model it's really hard to fit such additions.

The issue is that real tippers have those hydraulic actuators placed vertically and they extend multiple times over their base length, regardless of whether this is under the bed or at the furthest end.

Closest thing that actually makes sense to me to have the actuator always in correct direction is something like this: https://youtu.be/FNYkpLXe26c?t=76 (timestamp in video):

But I'm not really sure how far off this is from the knee redirection method as it's also a lever approach, but with tread instead of beams. The point of attachment is better IMO for heavier loads.

 

Meanwhile Olivierz built the model in blue.

https://rebrickable.com/media/users/photos/231361/119652.jp