LifeTrac II Fabrication

For those of you who are interested in replicating LifeTrac II – the second prototype of OSE’s open source tractor – here is the fabrication documentation that we have so far. This is meant to be used by dedicated co-developer-builders, who can contribute to improving the design. We still have to build Prototype III, and we are planning on the Full Product Release of LifeTrac on May 1, 2011. This would be after we complete Prototype I of the CNC torch table , which we will use as part of our digital fabrication optimization to cut parts for the tractor – thereby saving many hours of time per build. Right now, we need a design for an open source stepper motor controller suitable for the CNC torch table, as an open source version of the controller does not yet exist. As far as other open source fabrication optimization that we are contributing to RepLab, the Open Source Fab Lab – we are now using our open source 150 ton hole puncher and heavy duty hydraulic drill press quite successfully as part of every-day operations. These are all contributions to a low-cost tooling infrastructure for a serious open source, flexible/digital fabrication workshop. We look forward to the day that we could build all of these from scratch – by starting with scrap metal and an induction furnace.

For the tractor, start with the 3D design drawing in Blender, which is not just a pretty 3D image – but an exact model of the build that can be used exactly as is. The fabrication procedure of the tractor is documented on the wiki.

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:

Quick Attach Plate Fabrication from Marcin Jakubowski on Vimeo.

The design drawing is downloadable at our design repository:

There is one known bug at this time – we need to shorten the wheel base by about 12-18 inches – to make turning easier. Other than this, watch the tractor rumble:

LifeTrac II from Marcin Jakubowski on Vimeo.

We are finishing the Power Cube II and Soil Pulverizer II, and we’ll report on these next.


  1. LucasG

    Really looking forward to replicators replicating and documenting whatever they do.

    There’s still work to be done alerting people to this, then some of the alerted want to make it, and a further subset does it in practice.

    In some respects, that subset is possibly the most important at this stage.

    They might want to speak up with their intentions. No pressure, just encouragement and maybe some help from people who are local to you, and maybe even willing neighbours who can’t do 100% but can help with 5%. I suggest replicator wannabes could just send email to start a wikipage for your replication.

  2. Marcin

    As far as getting the word out – that applies to all of our projects in general. Part of the open source development procedure suggested in previous work calls for active recruitment of stakeholders. That means – remote collaborators on the OSE project are in a good position to take initiative to search and notify explicit stakeholders. For examples, we should be looking for organic agriculture, permaculture, low-cost housing construction, renewable energy, and many other stakeholders who are interested in low-cost products that can do more with less. Thus, I encourage everybody to spread the word – either passively, or actively – by actually researching, documenting, and contacting stakeholders.

    A good publicity piece on us can be taken from the book Plenitude by Juliet Schor. She devotes a full page on the description and potential of our project. Since it’s a mainstream book – it provides good material that can be quoted as an entry-level description of our work.

    A pitch could go like this – ‘These guys are making real products that make economic sense.’ To date, we’re run almost completely on donations – but that is changing – as we put real products into the marketplace. We have only one full product release (The Liberator CEB press) with breakthrough cost to performance ratio – and many more are forthcoming. That should be sufficient economic argument for supporting our work. People can support our work not only because it ‘feels good,’ but also because it makes plain economic sense.

  3. Abe

    I would really like to build a replicate of this, though a bit smaller. Any ideas for scaling down a bit?