Archive for the ‘engineering’ Category

2016 pruning, remembering Poppy

March 12, 2016

Today was the day for the annual spring pruning, and it was a great occasion to remember my grandfather, who died peacefully earlier this week at the age of 95.  William F. Herman (‘Bill’ around town, ‘Poppy’ in the family) was a big part of my life as a kid, and his love of growing things inspired me to plant the orchard when we moved back east over 10 years ago.

Pops and my grandmother, ‘Ummy’ grew up and lived their professional lives in eastern Massachusetts, but spent a lot of time in Maine – her father was an avid rod-and-gun sportsman. In the sixties they bought a slice of land on a remote island in the midcoast, two miles beyond the end of the electric power lines near the village of Five Islands.  When my parents decided to settle down after some years of teaching mountain-climbing in the mountains out west, Um and Pops invited them to homestead on the land in Five Islands, and I grew up off the grid, surrounded by the natural wonders of the Maine coast.

In 1983, Pops retired from a 25-year career at Polaroid, and my grandparents joined us in Maine.  By then electricity had come to the North End, and my father built them a passive solar home.  Though rocky and overgrown, the land had been a farm until early in the 20th century, with stone walls, foundation holes, and odd bits of pottery and rusted iron in evidence. Over the years the family cleared land and planted gardens, berries, and apple trees, and some of my earliest memories of my grandfather relate to agriculture.  He kept a very neat vegetable garden, which he would weed in khaki pants and a button-up shirt (he’d shower and put on a jacket and tie for dinner every night until he was far along in years). He grew masses of vegetables – great sweet corn, bowls and bowls of shell peas, and so many cucumbers and tomatoes that he put a wooden box at the end of the driveway and wrote ‘Help Yourself’, to the joy of the neighbors.

The garden was surrounded by semi-dwarf apples – Cortland, Winesap, Rhode Island Greening, Red Delicious, and he showed me how to prune the trees.  There was also a big wild tree behind their house that was saved in the construction, and it gave great green apples that were my favorite kind when I was a kid. In the fall we would collect the fruit in bags, and Poppy, Ummy, Joanna, and I would press them using a hand-crank cast iron press that had belonged to my great grandfather – the same press that Alexis, Holly, Becky, and I used back in Cider Year 1.  I think he tried to ferment some a couple times, but it was a casual attempt in a plastic milk jug and I don’t remember anyone thinking it tasted good.

In all the years of living and romping around as a kid, I can’t remember Poppy ever raising his voice.  He became a respected character around town, serving as selectman and sometimes as moderator at the old-fashioned town meeting. An engineer by training, he loved to keep careful records – of the amount of firewood he burned each month of each winter down to the tenth of a cord, of the number of quarts of blueberries his waterfront bushes produced, and of gallons of maple sap we collected each spring.  He taught himself to play ragtime piano by ear, and made some pretty nice oil paintings in an engineer’s realistic style – I think he said Norman Rockwell was his favorite artist.

If I drank another pint of this 2014 cider I could probably go on all night, remembering Poppy teaching me how to build kites and drive a tractor, and ‘messing about in boats’, fishing for mackerel in the Sheepscot river out of a 13′ Boston Whaler – he loved the water though he famously would never swim no matter how hot the summer. As the years went by, Poppy’s world gradually compressed; the boat trips shorter and the garden smaller and weedier, but he stubbornly kept at it. I remember a couple years ago when I was working in the orchard, I looked back toward the house and saw him at the edge of the field, using his old-fashioned scythe instead of a cane – he’d take a couple of swipes at the overgrown brush, then lean on the tool to catch his breath.

As Poppy slowed down my parents increasingly picked up the slack, mulching and pruning the berries, planting the corn, and splitting the firewood. And in 2006 I asked him if I could clear some land off to the the south to start a new orchard for cider apples, and he was happy to let me get started. For as long as he could walk, he’d totter up the woods road to the orchard gate to see what I was up to, and we’d talk about trees and plans.  I’m grateful to my grandparents for the opportunity to grow up in a unique and beautiful part of the world, and for the sense that tending and caring for the land is a project that can last more than a lifetime, and build connections across generations.

 

 

Pedal-Powered Cider in Cascadia

October 22, 2014

A fellow named Steve Haeseker in Vancouver WA sent me a note mentioning his very cool experiments with pedal cider equipment, and sending a link to his video:

The craftsmanship looks really nice. They use a small wood chipper coupled to a bike to grind the apples, and a pedal-hydraulic press made from a log splitter to do the pressing.  Then they feed the pomace to some cows.  The chipper is a neat idea, though the grind looks a little coarse (similar to our first-year results with the antique cast iron press).  I bet it could be modified to make a finer grind by grinding down the cutters and then tightening up the gap. But, given that a lot of apple grinding equipment (including ours) isn’t self-feeding, he may be on to something with the wood chipper concept, and I can see how fabricating a flat disk and mounting cutters to it could be a lot simpler than the multi-step machining process we used to make our cutter drum.

The press is made out of thick hard maple recovered from a bowling alley – major style points for that.  Unlike our press, they count on the wooden uprights to take the full tension of the press; it looks like they use a smaller cylinder (maybe 2.5″?) so the load will be less, but they still get good pressure by using a smaller cheese.  In watching the video it’s not clear why they need their cheese frame, since they aren’t really packing the cheeses full.  We have some instability in our cheeses that sometimes requires re-stacking the press; I wonder if we could do better by cutting the cheese frame down to 3″ from 3.5″ thick.  Alternatively we could make some shims that enforce a certain minimum cheese thickness until the stack is down to ~1/2 thickness; by that point the viscosity of the pulp will be much higher, and I’d think the stack would be less squirrelly.

Anyway, hats off to Steve for joining the ranks of pedal-cider enthusiasts!

Another reason we need wind, solar, electric vehicles, and heat pumps

June 15, 2014

A semi hauling diesel and kerosene tipped over in a rotary less than a mile upriver from us on Wednesday.  The image below is from the Portland Press Herald:

gorham stroudwater fuel truck crash

The article said that 6000 gallons were recovered and “Emergency crews were able to prevent the spill from entering the Stroudwater River”.  However the crash was only 1/2 mile north of the river, and  it rained heavily on Friday.  By Saturday morning the river smelled strongly of petroleum.

Modern life requires energy to power our transportation and heat our homes, but we can (and must) do better than dirty, unsustainable, de-stabilizing liquid fossil fuels.  We need to accelerate the development of efficient technology that uses less energy to get things done, and cost-effective renewable sources to meet the remaining demand.

 

19th century clean energy technology in Maine

November 10, 2013

As some readers know, we are fortunate to inhabit a beautiful spot on a small river in southern Maine, which was long ago the site of a water-powered mill.  One of the enigmatic relics of the ruined works was a 3″ diameter steel shaft sticking out of the muck in the riverbed, with a Lovejoy coupling on the upper end the size of a dinner plate.  Soon after we arrived, we made a preliminary effort to unbury it one spring afternoon, but if I remember it was hot and buggy, and we ran out of steam after digging down and finding the runner pinned under some chunks of broken metal.

runner in hole

18 months intervened, and I had basically given up the thought of finishing the job before winter, but Saturday dawned pleasant for working, so I took some buckets, a shovel, and a digging bar down to the site and was soon hip-deep in a mucky hole.  By a combination of bailing, digging, and pitching out rocks, I was soon able to get back to where we had previously stopped, and was able to rock the runner. With a bit more excavation I could see what I was up against – about half the circumference was trapped under a semi-circular cast iron ring, which had clearly been some sort of inflow nozzle that directed the flow downward onto the axial-flow runner.  The cast iron parts were not going to move, since they were bolted down to some structure buried even deeper in the mud, but I was pretty sure if I could pull the one main chunk off (to the right in the photo above), I could lift the runner clear.

At this point I was pretty confident of victory, so I texted Tony and invited him to join the fun.  Together we toted our light oxy-acetylene cutting rig down into the riverbed, and without too much effort we were able to burn off 3 nuts (or bolt heads; hard to tell with that much rust):

torching off nutsfire in the hole

The old metal was wet and covered with mud, so the cutting was pretty mangy, but I got them burned off and then knocked the slag away with the digging bar.  I lifted off the iron chunk, and then we had a pretty good view of the runner.  it appeared to be about 3′ in diameter, with 10 graceful sweeping vanes.

The runner was free, but it was way too heavy to lift.  However, we were fortunate to have two good-sized forked trees in line with it on either side; an ash on the manmade island between the main watercourse and the ruined spillway, and a pine on the high ground,directly beyond a steep  cliff that rose about 15′ above the riverbed.  We rigged a chain in the ash, a snatch block on the runner, and a second snatch block in the pine, and used our trusty orange worm-drive hand winch to take up the strain, with the red Ford as an anchor.  Once we levered it clear of the remaining bits of metal in the hole, it rose smartly thanks to Tony’s efforts on the winch:

starting to rise

coming out of the hole2013-11-09 14.51.14

We were about out of winch by the time the runner was clear of the hole, so I guided it over onto the riverbed and Tony set it down.  We lowered the attachment sling to just above the balance point, re-rigged to pull directly with the truck, and tied on a rope-a-long that was hitched to the south shore.  Then with the truck we quickly raised it until it was even with the cliff edge above:

runner suspended

We then winched it south with the rope-a-long while gently lowering it with the truck, to arrive at its new resting place on high ground:

closeup of runner up top

All in all a fun project, and a neat piece of Maine renewable energy history – I’m curious now to learn more about the mill that was at this site, and more generally about this type of small water mill.  My first impression is that this runner seems much bigger than appropriate for the flow of the river (which can be judged from the photo above, which shows the outlet of the millpond, roughly at the location of the ruined dam) – at least during typical summer and early fall flows.  Of course there are times in November and early spring when the entire valley fills with a raging torrent (see canoeing pictures from earlier this year) but I wouldn’t think you would build a larger-than-needed mill just to run on those few days or weeks of the year.  Maybe the process (sawing wood or what-have-you) had a relatively low duty cycle, and they’d let the millpond fill up between cuts, then open the floodgates to get more power when they needed it.

Cider year nine – roundup

October 26, 2013

After nine years, thanks to the accumulated contributions of ideas, time, and equipment-building effort, and especially to the wonderfully useful and flexible barn that my folks built, the cider operation is getting to where it runs in a well-worn groove.  And it’s a good thing, since the great majority of my attention has been devoted to Pika Energy, and building affordable, high-quality home wind turbines.  

truckload of apples

Two weeks ago I visited Autumn Hills Orchard in Groton, MA, and picked up two 600lb  bins of mixed cider apples – Kendall, Spencer, and Cox Orange among them.  The owner, Ann Harris, also kindly let me do some sanitation and gather a few hundred pounds of RI Greening drops, so the truck was quite heavily loaded down with apples for the ride home.  The going rate for cider apples this year is apparently $50/bin – illustrating the importance of top-quality fruit and value-added products to the economics of small orchard operations.  That same weekend I also needed to build and test a new wind turbine tower, as well as moving some cidering equipment up to Five Islands, so by the time I was fully loaded with dogs and bikes etc., the rig looked like some kind of Tom Joad/Johnny Appleseed chimera:

2013 big load of turbines and tower parts

 

The tower test was successful, and my folks and I unloaded the bins using a four-fall block-and-tackle that my dad inherited from a local gentleman, Don Spurr.  Don lives on in our memories every time one of his carefully-maintained tools proves to be just the ticket for solving some mechanical challenge:

emily lowers apples

The following Wednesday afternoon, Dave, Alexis, and I made the annual pilgrimage to Poverty Lane Orchard/Farnum Hill for cider apples.  I called ahead a couple of weeks, but for the first time in several years, we were disappointed that they couldn’t sell us a bin of bittersweets – they were too booked up with demand for cider fruit from as far away as Michigan and Oregon.  Brenda made it up to us by giving us a nice discount on the ~700lb or so of mixed cider fruit we collected.  We hauled the load with Alexis’ little Suzuki wagon, and it really drank the gas on the way home, but still burned far less than it would have taken to drive the big red monster all the way to the other side of NH.  When we got home, Fern got right into the action:

fern munches an apple

I managed to get up to Five Islands by mid-day on Friday, and on the way up I picked up the only big innovation in on the equipment front this year.  I bought a 100 gallon HDPE bulk tank from US Plastics, together with a hand-operated diaphragm pump rated for 15gpm.  Together, these made a huge difference in the management of finished cider during the big event.  Dave whipped up a wooden stand for the metal stand that I bought to go with the tank, so we could gravity feed into bottles and carboys.  Working the pump was a big hit with the kids:

Kate pumps the cider

 

Compared to commercial operations, we keep a very high standard for fruit quality going into the grinder; since we have plenty of labor and it’s a sociable activity, each apple is washed and inspected by hand, and any brown spots or other flaws are cut out.  But washing has always been an afterthought from a process standpoint, and in past years (especially when it’s cold) the washing itself hasn’t always been super-pleasant.  This year I grabbed some plastic bristle brushes at the Despot, and Holly and Ben whipped up a much more ergonomic washing station using an old washtub my dad found at the Georgetown Mall:

washing station

 

We started the festivities Friday evening with pot-luck Mexican at the shore cabin, followed by a black-powder demonstration (no bullets) by Jake, and revival of an old tradition, Viking Funeral Ships – in which small barges made of wood planks piled high with birch bark, pinecones, and kindling are set afloat after dark, and rocks are thrown from on shore at a sporting distance to smash them – if anybody has a photo of this, I’d love to post it.  

Breakfast Saturday was amazing as usual, with with Kelsey and Beth’s breakfast burritos and assorted pastry.  Cidering got fired up between 9 and 10AM, and continued on with a brief intermission for lunch, which was headlined by my folks with ‘Nebraska Cream Can Dinner’, a tradition they picked up out west.  As usual, we also fired up the bottling operation, kegging, carbonating, and bottling about 5 kegs worth of cider (minus ‘operational losses’ in the bottling step).  Here Tony and Rita prepare Cornelius kegs for transfer:

sanitizing kegs

 

Holly, Becky, and Heli took the lead on dinner, producing soups and amazing fresh baguettes. Here’s Holly working the dough:

holly makes bread

 

Dinner for 30-40 people was served in the barn this year, followed by Holly’s usual transcendent apple pies.  MomJones couldn’t make it to cider this year, but she sent us four large folding tables that made for a very convivial setup.  All told we produced approximately 207 gallons of cider, per the tally sheet, with an estimated yield of 69-70%:

2013 cider tally

Thanks again to everyone who participated this year. Next year is the 10th anniversary – I don’t know what we’re going to do, but it’s going to be big!

 

 

Debugging a Troy-Bilt sicklebar mower

June 23, 2013

With the Jari on the disabled list (burned up motor, leftside wheel, and shroud), I set to rehabilitating the 42″ Troy-Bilt sickle mower I bought last weekend.  It started right up when I bought it, but it had a damaged belt, which I thought was the reason it jumped off the pulley when I engaged the sickle bar.  So I bought a new belt (1/2″x35″, for future reference), put it on, and it fired up the cutterbar, but it too jumped the pulley as soon as I put it under load.  There were two little bent steel ‘keepers’ on either side that seemed designed to keep the belt on, but they only extended halfway down the axial depth of the pulley, so I thought maybe they were insufficient, and I made better ones out of scrap aluminum.  However, as soon as I started to cut grass, the belt jumped the pulley again, and my new keepers very effectively ripped the belt in two.

mower broken belt

 

At that point I suspected something more fundamental, and in looking carefully I noticed that the motor pulley was axially mis-aligned with the cutterbar pulley by about 3/8″.  Joshua and I puzzled on it for a bit, and we noticed that the pulley was held on the end of the shaft with a suspiciously non-factory-looking bolt and stack of washers.  To my surprise, the pulley was not frozen to the shaft, but rather moved easily once the set screws were released.  I tapped it up into alignment:

mower shaft

 

Given the retrofit bolt arrangement, I didn’t judge that the set screws were capable of holding the pulley in place, so I whipped out a spacer on the Bridgeport – didn’t have round tubing the right size, but 1″ thin-wall aluminum square tube fit over with a bit of encouragement (must be a 7/8″ shaft):

mower shaft with spacer

 

I Secured the pulley with the bolt and washer stack, reassembled using the old belt (not about to blow another brand-new $14 belt on this mower), fired up, and it cut nicely for about 100 yards.  It was too hot in the middle of the day to really put it through its paces, but I think we’re provisionally back in the sickle-bar mowing business.

The Troy-Bilt seems a little slower than the Jari, but has 10″ of extra width, so they probably will work at about the same rate.  It’s a wider, heavier machine with janky plastic catches on the levers for the tank-style independent steering clutches, and at first go I don’t like it quite as much, but I suspect I’ll get accustomed to it.  Still, since I think I have a spare engine that will fit the Jari in place of the burned-up unit, I think I’ll order a replacement wheel and try to put it back in service eventually, as limited spare time permits…

Pedal cider press does off-season duty as a broach

June 21, 2013

I’ve needed a hydraulic press on a couple of occasions recently, and haven’t felt like buying one of those clanky steel-frame jobs with a bottle jack – so on the last trip to Five Islands I brought back the cider press and bike-hydraulic setup, and we’ve been using it in the woodshed as a 20-ton press.  While it doesn’t have the adjustability of the steel presses, it does have a 24″ stroke, which goes a long way.  Here we have just finished broaching a Lovejoy coupling to accept a key:

press used as broach

 

I have a notion to upgrade the pedal-hydraulic power unit to make it less janky and more portable, making it better suited to other applications, such as operating a worm-drive winch to raise and lower wind turbine towers.  But in the meanwhile we might as well keep it well exercised…

Jari Mower rehab, rhubarb pie

May 28, 2013

The grass is growing rapidly and Saturday was a washout, so I took advantage to make some repairs to the Jari mower that  I bought for $125 two springs ago.  It has worked well for us, but the carburetor has been loose on its bolts for a while, and they were frozen into the cylinder so I couldn’t tighten them.  The two bolts holding the carb to the cylinder were hex head bolts so tightly housed in the casting that it wasn’t possible to get a wrench on them, so they were also cross-slotted for a large screwdriver.  The whole thing was clusterific, so I ordered a box of 1/4-20×3/4″ socket head cap screws from McMaster, and shortened the short end of an allen wrench so it would fit into the available space.  I cleaned up the mating surfaces as best I could, and reassembled with lock washers and some loctite (not sure how the loctite will do on a hot engine block), and with fresh gas and a shot of ether it fired up and ran happily.

sprag-clutch

I also cleaned the chaff out of the flywheel fan assembly; Jari adds a perforated steel intake screen over the flywheel, but there’s a hole in it where the recoil start enters, and it still sucks in an incredible amount of grass.  The centrifugal ball clutch is protected by a second, finer screen and a rubber bushing, but amazingly even that manages to fill with fine organic matter, to the point where the balls lodge in the clutch housing and won’t catch.  It’s gotten to be a sort of set routine to unbolt the flywheel cover (7/16 ratchet), remove the cover (1/4″ nutdriver), pry off the retainer cover (Swiss army knife), clean out the dust, and reassemble.

When I got the mower there was as much water as oil in the crankcase and it hadn’t run for years; at this point I’ve spent several hours fixing up this mower and I’ve developed something of an affinity for it. There’s something endearing about a small engine that seems to want to run.  The annoyance of keeping at least a half-dozen small engines running around a typical homestead (tiller, sicklebar mower, rotary mower, log splitter, generator, water pump) makes me think from time to time about a nice powerful BCS walk-behind tractor, but at $1500, the cost of just the log splitter attachment for the BCS is greater than the cost of many stand-alone log splitters  – of course you don’t get the cachet of the fine Italian engineering.

What would be really great is if Marcin Jakubowski and company over at Open Source Ecology would design a good open-source walking tractor, rather than trying to re-invent the skid-steer loader.

Bridgeport milling machine

December 23, 2012

To a mechanical engineer, a Bridgeport is the iconic machine tool, the basic necessity for doing precision work, and I’ve felt increasingly hamstrung by the inability to whip out simple components or modify parts we buy.  I looked at a smaller Jet machine, but it was missing a couple of degrees of freedom that I’ve actually found quite useful recently, it didn’t have quill feed or back gear, and I scraped my knuckles trying to adjust the five speed belt drive – I could have swapped the single phase motor for a three-phase and run a VFD, but that seemed like too much work for a compromised machine.  So I found a mid-eighties Bridgeport with variable speed on Craigslist, and checked it out last weekend.  It looked pretty good, so today Joshua and I went to southern NH to pick it up.

The owner was an older German gentleman who had made his living building big pieces of equipment, and he had a large forklift which made the loading part simple.  We had a half-ton pickup with a 1500lb flatbed trailer, and the pickup probably could have handled the whole tool (it has the heavy suspension b/c snowplow) but getting it from the high bed of the trailer to our shop floor would have been a real trick.  So we took the head assembly off the column and put it in the truck bed.  We unbolted the head assembly from the column and lifted it off with the forklift, then bolted it to a couple of 2X8s cross-wise, which we then screwed to a pallet and skidded it into the truck.  We then hooked up the trailer and arranged more 2x8s crosswise underneath the column, picked up the column, and slid it into the trailer, adjusting the position to get suitable tongue weight.  We used wide nylon ratchet straps left over from Joshua’s boat to lash it fore and aft, and got on the road.  I have had bad experiences hauling heavy loads in these little Snowbear trailers, so we took back roads for the first 20 miles or so, then stopped to check the tires (slightly warm) and wheel bearings (stone cold) before getting on the  freeway.  Fortunately we made it home without incident.  Here is how the load looked when we arrived:

the load

 

Then came the fun part.  Lacking a forklift, we had to resort to Egyptian methods.  We carefully backed the trailer until its rear end was over the threshold of the door, then chocked the wheels and jacked the tongue with a Hi-Lift jack until the tail grounded out on a 4×4 on the sill.  We then screwed some 4′ 2x scraps to the 4×4 to create a ramp, and rolled the mill onto the shop floor on 1.5″ pipe rollers, controlling the speed by snubbing against the hitch ball of the pickup:

jacking the trailer

 

rolling off the column

 

Once on the floor, we could roll the column around easily, though changing direction was more difficult.  The trickier part was getting the head assembly off the truck and onto the column.  We started by fabricating a u-bolt out of 1/2″ all-thread to hoist from, and installing it on the underside of one of the I-beams that make the (relatively unconventional but extremely stout) first floor framing of the south house.  We hooked a pulley to the u-bolt, and ran the bitter end of a rope-a-long through the pulley and to the eye on the top of the ram.  The main complication was that the truck was too wide to fit through the double doors.  So we fabricated a rudimentary platform to skid the head assembly off the tailgate and under the hoisting ring. We could have done a better job of this and the transition was a bit sketchy, but we had the assembly supported with the rope-a-long.  We also put a sling around the head itself and used a second pulley to keep it more or less level as we winched it up:

hoisting head assembly

 

From there it was relatively simple to lower the head assembly onto the column and bolt it together – there’s a funky spider casting that holds the head down, but with a bit of fiddling we got it lined up.  We skidded the assembled mill (significantly more top-heavy now) into its assigned corner, and set it down on some rubber pads:

in place

 

Next steps include leveling the machine, wiring it to the VFD I bought, tramming the head, and throwing up a fast-and-nasty partition to keep the wood dust from the rest of the shop out of the works.

Open Source Ecology

September 29, 2012

A day or two ago I heard a piece on NPR about a guy named Marcin Jakubowski who is on a mission to design and build the Global Village Construction Set, “a modular, DIY, low-cost, high-performance platform that allows for the easy fabrication of the 50 different Industrial Machines that it takes to build a small, sustainable civilization with modern comforts.”   As described in a short TED talk, Jakubowski explains that he was a theoretical physics student, started farming when he felt that he lacked practical skills, and had bad experiences with old farm equipment that motivated him to design simple, practical open-source tools. This evening I checked out the website of his organization, opensourceecology.org,  which has a work-in-progress wiki-based compendium of concepts, specifications, designs, fabrication videos, and test images.  The group is big on modularity, hydraulics, and structural steel, and they’ve done a pretty impressive amount of development on a few of their concepts, including a skid-steer tractor and an automated press for making rammed-earth blocks. They are based at Factor e Farm in Missouri, which reminds me a lot of stuff I’ve read about the New Alchemy Institute.

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