Girl Mark's
home biodiesel class

Four Elements Herb Farm


Girl Mark, the mother of the "appleseed processor" and grass-roots activist, spends a great deal of her time for very little money spreading the word and passing on the skills to make home-brewed biodiesel.  Her website at has extensive information and a forum for questions and answers regarding pretty much any part of the process and is an amazing on-line community of biodieselers that have a weath of knowledge and experience to share.  I was lucky enough to make it to Mark's seminar in Atascadero, CA last During the 2-day seminar we covered the chemistry behind biodiesel and principles of home production.  We were walked though the oil titration, de-watering, made small batches including test and demonstrations batches with "bad oil".  On the second day, those of us who wanted to started to build our own processors to complete at home.  All of the production that we've done at home is based on the Biodiesel Homebrew Guide by Girl Mark



Biodiesel review and gallery

Girl Mark's class gallery


Biodiesel Links:

Collaborative Biodiesel Tutorial 

Utah Biodiesel Supply


The S.E.E.P. environmental blog 

The S.E.E.P. Store 

Slaughter Productions home


The Music Machine

Strawbale Hobbit House

Shipping Container Accessory House





here Girl Mark is explaining the functioning of the 4 Elements Herb Farm processor.  They have 2 wash tanks, one welded and the other scavenged from the trash.










The Four Elements co-op showed the class how they use the processor.  In this step, they are draining off the waste glycerine. 










This is the reed greywater filtration setup for the waste washwater.











Mark explains the chemistry of the trans-esterification process.











eager young hippie chemists listen to the lecture










Mark showed examples of "glop" which is what happens with "bad" oil/sloppy calculations/improper setups and likely any major screwup.









This is the titration equipment for the class.  Improper titration can cause our friend "glop" to be produced instead of useful biodiesel.










We made small batches in 1 liter bottles in just a few minutes.









Hugh pours some of his free soy-sauce byproduct oil sample.  Unfortunately it turned out to be too wet.  He had a great source!












The class starts to disassemble their used hot water heaters. 







I was last-minute and bought a new water heater from Sears, making mine a little easier to get apart to put the new plumbing on.












Fitting together the lower plumbing portion of the processor.











The first version of the processor that I finished at home. 





I have since changed to motor pictured to a self-priming pump, added a T-piece above the motor for transfer to a fuel pump, and changed the output setup slightly to allow me to control flow or shut off the output from the tank, making the pump suction more effective when drawing waste oil into the reactor as well as improving the flow of methanol/KOH into the reactor.