LifeTrac Prototype I

Here is the evolution of LifeTrac (see wiki work page) from design, possibly the most simple implementation of tractor-loader functions:

to steel frame:

to wheels and motor,

and to bucket:

I completed the quick attach plate yesterday, from design:

to fabrication:

The plate mounts on the front end loader arms, instead of the bucket, and is based on similar designs used for this purpose. The quick attach plate is used to attach any implement on the front end loader. The triangular quick-attach fingers grab the implement of interest from below, and the implement is then fixed to the plate using the two horizontal pins in the picture. This way, we can switch between the loader bucket and rototiller (or any other implement) in under a minute – which will come in handy with soil preparation and loading in CEB construction. Today, I’ll be designing and fabricating the rototiller. I hope to be done by tomorrow. This is just the beginning of the entire LifeTrac infrastructure.


  1. Lucas

    Yesterday, today, tomorrow. Can’t get any faster than this. Wow and thanks.

  2. Abe

    What is your cost for the prototype LifeTrac? I am very interested in this design, as we are in a similar situation as Factor eFarm. We are in rural Mexico, homesteading 10 acres of hilly terrain. We need some water storage, and a tractor, specifically a digger is going to be a big advantage. We dug our house site by hand, 4 ft deep, 50 ft long, as the house is partially buried into the hillside. YIKES! It was a chore, and some sort of machine would be nice.

    But, as always, price is definitely a factor. I can get a small digger for about $2500, but without a PTO, so that’s about all it can do. the LifeTrac seems to be a viable option, if the fab costs are low. I can get anything from Surplus Center, but lots of the parts I will be available to find locally.

    Anyway, a rough price tag would be helpful.

    Abe- our cost was $5k for what you see in Factor e Live 8. Maintenance costs are $100-200/year- as opposed to $1-2k for a machine of that capacity. I do not recommend a cheap option like a $2500 digger – the thing will bury you with maintenance costs. That’s exactly what we did – I got a backhoe for $1500 – but it had its share of problems, and I have no control over whether it breaks down tomorrow. So we’re stripping the backhoe off and converting it to a quick attach implement on the loader of LifeTrac. That’s our story.

    The good news on price is in the following post that I submitted at Globalvillages Yahoo group. Help us make it happen, sooner rather than later:
    From post to Globalvillages regarding applicability of LifeTrac to Africa:

    Here is one scenario that we have in mind for OSE-USA. At Factor e
    Farm, our near-term (within 2 years) goal is to produce the following
    infrastructure for building LifeTrac, the open source tractor
    ( on the cheap.

    Note that presently, the basic LifeTrac implementation with loader is
    $5k for parts. Note that a machine of similar capacity would sell for
    about 4 times more than this on the commodity market. Now here is a
    radical proposition: we are aiming to produce the same for the price
    of scrap steel and iron that goes into making the machine. That is
    about 10 cents a pound, or $300 for the present 3000 lb tractor. Well,
    we won’t be able to do it this cheap, as you still need tires and
    bearings, and hydraulic hoses, which we would initially outsource.

    I propose that it is within the realm of appropriate technology,
    fueled by open source design, to produce a tractor as such in a
    community supported manufacturing scenario. This applies in the West
    and in the developing world.

    Start with scrap steel. Melt it down with small-scale foundry
    processes, and cast metal tubing, shaft, bar, and sheet. Do likewise
    for steam engine castings for the engine. Do likewise for hydraulic
    pump and motors. All these are basic technologies – if one has design
    blueprints. Use a Babington burner (blog) for the fire. Multimachine
    (blog) is necessary for drilling holes and machining operations. Not
    even an acetylene torch nor welder is necessary in this scenario.
    Castings may be programmed and printed by RepRap (blog).

    This is like science fiction – but in reality is not much more than
    using proven technology. Reduce that technology in scale to the
    village level – and you have appropriate technology.

    So one particular aspect – if tractors are in demand – is to produce
    such tractors in small shops, starting with fire and scrap steel.
    Doable – in Africa and America – though I’m nut sure what your scrap
    steel supply is like.

    In any case, we aim to have a tractor as such developed here in 2
    years – scrap steel, steam engine power, Babington fire, cast
    hydraulic motors and cylinders and cast hydraulic pump. Run that on
    bio-oil from distilled wood, and bio-oil instead of synthetic
    hydraulic fluid – and you have a largely local resource-based tractor.

    I propose this as one avenue of weaving a story for possible local
    economic development.


  3. Abe

    Yeah, I agree with you, starting from the ground up is the way to go, however for a one-off type of machine, it wouldn’t be worth it. I could see a market in our area for cheap tractors, but very few people have $3K to spend on a machine. They have horses, which are far less maintenance, and actually reproduce themselves!

    But, a horse is not great for digging. Also, it doesn’t have a PTO for other applications, like a chipper.

    I could see us making similar, watered-down version of the LifeTrac. First off, we don’t need the power you need, so we can use smaller components. Secondly, cheap scrap metal is actually VERY available to us, and I think we could even find an exiting frame to start working on.

    Our main needs would be digging, road maintenance, and a chipper would be nice. So, something more in the 20 HP range would be feasible. The point here is, design for your needs. Smaller is ok for our needs, and will be less cost overall as well.

    Wood gas would be a good way to power one of these units. You could build a simple chiper to process the fuel, and then use it to power the tractor. It would be a simple start to growing and self-processing your fuel needs.

    Good work on the prototype, and I would love to participate any way that I can. Right now, I think our contribution might be to build a smaller prototype that fits our needs, and try and find most of the materials locally, here in rural Mexico. Some thing would need to be new, like the engine, but the frame and most of the metal, could be salvaged easily.

  4. Marcin

    You can see the hydraulics design and other details at

    Rototiller, auger, stump grinder, chipper, swing-blade sawmill, and well rig coming right up…

  5. Vaughn

    When I saw your rototiller attachment it made me wonder if anyone at Factor E has had the opportunity to read about the keyline concept. Seems like making one of the keyline plows would be even easier than the rototiller.

    True sustainability, eh? Here is one link…

    Here is an updated book by a second (third?) generation user of keyline principles

  6. […] compacted clay – the prime soil for CEB construction. So we are doing further improvements on LifeTrac. The first step is adding a smaller loader bucket – with a tooth bar for ripping into the soil. […]

  7. […] and production facilities – with the CEB Press powered by a high-performance, open source tractor, LifeTrac – which we also designed, built, and are testing it in the field. This tractor is also used in site […]

  8. […] off-grid operation. The month of October was taken up primarily by field testing of the open source LifeTrac/CEB/rototiller/toothbar bucket/backhoe combination – as applied to site and earth preparation for […]

  9. NLP Zine

    Interesting blog post. What would you say was the most important NLP factor?

  10. […] where we can model the heights and angles required prior to building. You can see our initial designs from over a year ago for reference – on the evolution of the project. Addendum: Our experience has shown that it […]

  11. […] the LifeTrac II budget involves completion of quick-attach plates, fabrication of steel wheel tracks for added traction, and outsourcing wheel coupler lathing, since […]

  12. […] which was shown briefly in the video above – has been completed successfully. It has been proposed first about 2 years ago, and we have finally built it. You can download the design for the quick attach plate here, as well […]

  13. LifeTrac II Fabrication | Factor E Farm Blog

    […] Two years ago we proposed the quick attach plate lever mechanism for the Quick Attach plate on the tractor, which we never implemented on LifeTrac I for lack of time. Instead, we just used pins to lock an implement in place, as seen in the last link. Now we have the working lever, which is much quicker to engage, and is worth replicating as a useful, open source mechanism. See the fabrication procedure for the quick attach plate and latching lever: […]

  14. […] On the wheel drive, we are now working on quick release wheels – ¬†where a cam mechanism and 1-2 bolts allow you to take off entire wheel assemblies on LifeTrac – in under 5 minutes. This is a great step forward on LifeTrac’s direction as the world’s first life-size Lego tractor. We have already shown quick interchange power units, ¬†design-for-disasssembly (bolt-togeter) construction, interchangeability of motors, and quick-connect implements. […]

  15. […] rotor starts to vibrate excessively when in heavy brush. This is an artifact of our existing quick attach plate, which has manually-insered pins for locking. Since the pin holes are oversized, small implements […]