Coffee that you can trust.



Running Green Bus and the roaster seems like the culmination of a lifetime of tinkering.

To me, fixing stuff is a metaphor for the more important, non-stuff, aspects of life.

Hence this blog.  It concerns the technical aspects of building and running the Green Bus and its associated support mechanisms.  Buying, renovating and maintaining a bus will either drive you mad or strengthen your philosophy.  This particular example is a 1996 International diesel with a Bluebird body that was transformed into a mobile kitchen in Ontario, Canada.  As with all such adventures, it is a work in progress. 

Throw a coffee roaster into the mix, and things get even stranger.

If you have any comments, you can reach me at: .




October 31, 2015
Blame it on El Nino

Should you ever get the notion to convert a school bus into anything, please consider the matter of temperature control.

A school bus makes a fine greenhouse.  The same generous window-acreage that gives the interior of the bus such a cheery brightness lets in plenty of heat on a sunny day.  On a cold day, that is a good thing as it warms the interior.  On a hot summer day, however, the bus becomes a furnace.  Throw in a busy coffee roaster and a gas stove baking a half-dozen serial batches of cookies, and you have a recipe for meltdown.

Our bus (a Bluebird, but most others are similar) has minimal insulation, and retains little heat on a cold day.  On a chilly fall day, even with the roaster going steadily, it takes an hour or two for the place to feel warm.  On a winter day, auxillary heat is needed to warm the place up.

There are a few things that can help these temperature issues:

  -  trees are a handy thing.  park in the shade.

  -  open the windows.  School bus windows are notoriously cranky to close, but keep the tracks clean, a little teflon spray helps, and develop a practiced snap of the wrist with even pressure on both sides, and voila!   Food regulations require screens, and if you use propane in the bus as we do, you will find that the interior becomes a huge mosquito magnet.  We have used velcro and magnets to hold screens in place with some success.

  -  The ceiling of a school bus is a dome that holds heat very neatly.  Even with windows open the dome retains heat.  It needs to have a roof vent.  Many newer buses have roof vents installed.  Ours did not, and I installed a small solar-powered vent and fan, which makes a big difference.

We plan on a few other modifications:  an awning to shade the windows on whichever side is sunny;  an air-conditioner for the really impossible days.  I can let you know how that works out.


December 10, 2014
On being grounded.

The Green Bus roaster is a TJ-067.

The good folks at Mill City Roasters in Minneapolis sold it to us, and we are quite happy with it.  It is solid, quiet, easy to control, and works equally well with propane or natural gas (after changing the jets).

Up until now, I controlled it manually, and logged roasts manually using pen and paper.  The roaster, however, came with a USB interface and an extra temperature probe to allow roast "profiling" with a computer.

It proved a vexing technical problem.  I was getting inconsistent temperature readings from the bean probe.  Often they were several hundred degrees off, and other times they just got stuck in one place, or they fluctuated  in a seemingly random manner.

I was using a linux box, and I put the problems down to my limited ability to diagnose driver issues in trying to get the profiling program (Artisan) to talk sensibly to the USB interface (a Phidget 1048).  After spending many hours searching the internet for information and trying new approaches, I conceded defeat and hauled out my old Windows XP laptop.

Within 10 minutes I had Artisan loaded onto Windows, the Phidget drivers were installed, and the temperature readings seemed to work miraculously.

Pleased, I rearranged my workspace to incorporate my old laptop, and did a final test run to make sure everything worked.

Alas, the temperature readings resumed their wild and inconsistent behaviour, just as they had under the linux box.

So I made myself a cup of coffee while I pondered this latest attack by the forces of Entropy.  Maybe it was the coffee that fixed it.   Maybe it cleared my mind, focused my attention, and allowed me to see that the program worked properly whenever the laptop ran on its battery, and messed up whenver I had the power supply plugged in.

It was a ground loop problem.  There was a ground voltage difference between the roaster and the computer, which can be fixed by using a USB isolator, by insulating the probe, using an ungrounded thermocouple, or by keeping the laptop ungrounded. 

How simple problems can seem once a clear perspective is found.

November 8, 2012
A Word on Paint.

Before you decide to renovate a school bus, you might want to consider the question of paint.  As is often the case with bus issues, it is the size of the beast that causes the problems.

If, like most of us, you don't have a garage large enough, you will be working outdoors.

If you are renovating a bus you are probably not rolling in cash.  A bus will need a fair bit of paint, and that fancy automotive stuff is fairly pricey...

How long is the hose on your compressor?

A good paint finish requires good surface preparation.  A school bus has a BIG surface to prep.

If you don't have a squad of helpers, do you suppose you will have time to tape off all the windows and fixtures for proper spraying?  Before the next rainfall, that is...

Are you starting to see the picture?  Painting a school bus, through sheer size, is a little different from painting a car.  Cindy and I settled on buying gallon cans of rust paint and using brushes.  The result looks a bit rustic, and the finish is not the glossy perfection one might find on a auto-showroom floor, but it was do-able and suited the spirit of the project.  Ultimately, we came to see the project as more akin to painting a house than painting a vehicle.

The biggest challenge we faced was the deer-flies.  They were fierce, making our task sometimes miserable, and they also tended to land in the wet paint, dying as artistic textural flourishes.  Our property is well treed also, and along with the flies there are more than a few pine needles embedded in the paint.

On a philosophical level, painting a school bus brings you face-to-face with your own notions of perfectionism.  Most of us appreciate a flawless paint-job on a car or truck, but in the case of school-bus renovation one has to be realistic.  If you are a true perfectionist, you might want to stick to building ships-in-bottles, or designing the perfect martini, and leave school bus renovation to the pragmatist.


June 29, 2012
Shake, Rattle and Roll

A school bus is just a very long truck.  It rides hard.  Its suspension lacks the silky smooth, isolated feel of a coach.  As a result, stuff rattles.  Care needs to be taken to see that tables, sinks, shelves, metal panels, and every other item that is attached to wall, ceiling or floor, is attached firmly and in such a way that it does not rattle or shake excessively.

The first time we took the bus on the road - a relatively smooth highway at that - we were amazed at the cacophony of noise coming from various places.  The sink boomed.  The stainless panel behind the stove was as loud as a dozen schoolkids.  Every loose item that was not packed with soft care rattled like a banshee (although not being Irish, I have never met a banshee).

Keep the rattles in mind when you build your bus.

November 5, 2011
Give me forty acres


The driveway seemed like a good, generous driveway.  It has a wide entrance from the highway.  The gateposts are far enough apart to hold a full-size farm gate.  The trees are trimmed well back from the gravel.  The turning circle is big enough that its eye could hold a decent size house.  The drive has hosted a variety of tandems, septic pumpers, stretched out duallies, trailers and other out-sized denizens of the highway food chain.

So, having said all that, why did I feel like a hippopotamus attempting to use an airplane washroom when I brought the bus home and tried to wheel it into its appointed parking spot?

We managed.  It cost us a little scraped paint and a seven-point turn, but we managed.

All I can say is, before you bring a school bus home as your driveway pet, have a look at the scope of your driveway, and give it some careful thought.

Think, "Epic".

Perhaps invest in a long tape measure, be generous in your estimation of how much room you will need for the bus.  Don't think in centimetres, but rather think of the metre as the smallest, trifling unit of length that someone of your largesse would even consider.

When you are finished, multiply by two.


November 1, 2011
On Removing Seats

I can still hear myself saying it.  At the time Cindy and I were standing in a school bus.  It was a beauty, and we knew it would be perfect for our planned mobile kitchen.  My words were something like, "Wow, look at all those seats!  I'll soon have those out!"

Have you ever wished for a little bell that would quietly ring beside you every time you said something stupid?

A 13 year old, full size Bluebird bus riding on an International chassis has a lot of seats.

Twenty-four of them, to be exact.

Up here, in Ontario, where the roads are salted, and any exposed steel fasteners quickly transform into rusted gargoyles, there is no easy way to remove them.

Wrenches of all kinds, vice-grip pliers, penetrating oils (do they ever really work?), hacksaws, chisels and hammers proved ineffective.  Eventually, an angle grinder was settled on as the weapon of choice. 

Keep a fire-extinguisher handy.  Wear some hearing protection;  the grinder is even noisier than the 72 kids.  Use a thin blade, be mindful of where the sparks go, stop when the floor starts to smoke, keep your shoes and pants away from the stream of sparks, and watch where the red-hot pieces of cut-off metal get to.

You will be amazed at the variety of detritus that inhabits the spaces between seat and bus wall - a whole universe of sticky candies, wrappers, pens, pencils, old notes, hair doodads.  It will wake the archaeologist within.

And what to do about all the seats?!