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03/23/2010: "One With The Machine"

Click on photo above to view movie (warning large 6430k Quicktime movie file)

Richard Heinberg, in his book "The Party's Over," refers to humans as going beyond mere tool-making. He says we equip ourselves with prosthetic devices that allow us to accomplish much more than what our bodies alone are capable of. The example he gives is that of an airline pilot; a pilot apparently once said to him that he "straps on a 747 and goes to work." And thus the 747, in effect a prosthetic device or super-tool, allows him to fly thousands of miles while in effect carrying hundreds of passengers.

This past weekend I strapped on the back hoe down at the farm and went to work digging trenches.

The backhoe that I have attaches to the back of my Ford 1920 tractor. It gets its hydraulic feed from the rear remote valve, which it turns out is not ideal. However, it works well enough to get me through projects like digging trenches. It also turns out that the hydraulic flow volume is not the real limiting factor for backhoe work at the farm; the real limiting factor is how often you have to re-position the tractor/backhoe combination because you've dug out all that you can reach. I remember discussing this with my friend Bobby prior to purchasing the backhoe; he counseled against buying this type of add-on backhoe precisely because it slows you down too much to have to change seats and drive the tractor forward. However, I didn't want to spend the big big bucks for even a used mini-trencher, and I can't even rent one because my truck is too small to tow one. So, I live within the Woods Groundbreaker X's limitations.

It's been almost a year since I've done any backhoe work (the last bit I did was digging the trench for the cottage water supply). Getting in the seat I was a little concerned that maybe I had forgotten how to use the darn thing... I needn't have worried. It all came back within a matter of minutes. I judge my backhoe performance by how full I can get the bucket while keeping the bucket in constant useful motion (it's easy to keep it in constant non-useful motion overshooting where you want it to be, etc!). Starting off my buckets were about half full most of the time, with an occasional full bucket thrown in. A hundred feet down the trench I was hitting almost all full buckets, and I had turned the RPM up a notch to make the hoe move faster... at the end of the first trench I was getting overflowing buckets for the most part, with an occasional clinker of a three-quarter full bucket.

The key, I found, was to visualize the how arc of the dipperstick (the long link connected between the boom, which is fastened to the tractor, and the bucket) was going to move in the trench. The boom would set the height of that pivot point, and as you're working you have to imagine how the dipper is going to swing toward you as the bucket picks up dirt. In general, to get a flat bottom trench you have to be simultaneously raising the boom while extending the dipperstick piston (which is a pull on the lever, by the way). I learned that having more engine RPMs helped, as did not straying too far off the center position of the valves. You want to start pulling in the dipper, then alternate a little between pulling the dipper and raising the boom, with an occasional twitch to the left to curl the bucket a little more as you progress. It's like a delicate dance! There's huge satisfaction in pulling it off once... twice... shoot, scrubbed that one... OK, nailed that one! It's satisfying work, I'll say. After a while you really do start to feel like one with the machine.

I learned to be efficient about moving the tractor, too; you want to move it just to the limit of your reach with the bucket at the depth at which you're trying to work. I found that if I set the dipperstick with about eight inches of rod showing, then put the bucket teeth pointing straight down, then lower the boom until the teeth were just above ground level I could use the backhoe itself as a gauge for how far to drive forward. I would drive the tractor forward in its lowest gear until I saw that the bucket teeth were at the edge of the trench, then set the brake.

The only problem with full buckets was that I was becoming pretty efficient at getting dirt out of the hole, and that meant fewer cycles between repositioning the tractor. Pretty soon I was down to something like five scoops between tractor moves. Each scoop takes between 15 and 30 seconds, depending on how picky I wanted to be about a flat bottom in the trench. So it would go:

Scoop
Scoop
Scoop
Scoop
Scoop
Put the dipperstick, bucket, and boom in calibrated position
Raise the outriggers that stabilize the backhoe
Jump off the backhoe, taking care not to disturb any levers
Jump on the tractor
Release the brake, engage the clutch
Put the tractor in gear
Release the clutch, drive forward about 6 feet
Put the parking brake on, engage the clutch
Take the tractor out of gear
Jump off the tractor
Climb on the backhoe
Put down the outriggers
Scoop
...

Really, it must have looked like the proverbial Chinese Fire Drill, since this sequence repeated about every five minutes! I asked my daughter to take a movie of my prowess on the backhoe itself, and now I'm kind of wishing that I had asked her to film the re-positioning action just for the humor itself. If you'd like to see the movie, click on the photo at the head of this posting; just be warned that it's a Quicktime movie, and it is fairly large (6 meg approximately). It will open in a new window.

Here's a photo of the day's work: two 200 foot trenches. Not bad for less than three gallons of diesel fuel, eh?



Looks like I'll be back next weekend to dig two more trenches, and start the trench that will connect them all together. Then I'll have to order in some river rock, fine-tune the grade (water's gotta flow downhill and all that), get the drainage pipe in the hole, put the rock in the trench surrounding the pipe, get some permeable membrane over the rock and pipe, and then fill in the trenches. Still a lot of work to do on this project!

Meanwhile, Lou's been doing spring cleaning and organizing. Most recently he has transformed the shop: compare these new pictures...







... with this old picture from a couple of months ago:



Big difference!