Fedco dates: (http://fedcoseeds.com/trees.htm)
Discount deadline: January 18th (final March 8)
Scionwood deadline: Feb 22nd (ships March 20)
Preorder tree sale: April 26/27
MOFGA scion exchange: March 24 (also a grafting lesson IIRC)
MOFGA grafting workshop: April 28 (I hope this is updated; it doesn’t say 2013 anywhere on the page)
Some folks have asked for more design details on the post-crushers we use in our pedal grinder. I’ve put a link to a PDF drawing under “Cider Equipment Plans” over on the right. If anybody wants actual CAD files, email me at firstinitiallastname at gmail.
The concept is basically that you want two drums with shallow ‘teeth’ that are deep enough to engage the apple pulp and draw it through, but not so deep as to get clogged up. We were constrained in designing the tooth shape by the cutters that were available at local stores (in the end we used a router bit that we found at Sears), but we played around a bit until we found something that made a decent interlocking shallow tooth. It’s not perfect, it’s not an involute, and you have to be careful that the shapes have clearance when the tooth is lined up directly with the slot on the mating drum, but also that they pass clearly into and out of that point – the ‘gearing mate’ feature in solidworks was handy if I remember correctly.
As to the fabrication process, IIRC it went something like this: UHMW Polyethylene round stock; it routinely comes larger than advertised, so 5″ should be fine – at least from McMaster. We bought a 12″ chunk and cut it into 2 pieces. Chucked it in the lathe with a 3-jaw chuck, and drilled it through at 3/4″ – may have reamed it too, if we were feeling anal. Then we broached it to 3/4″ hex. That hex broach will cost real money new, but Holly has managed to find decent used ones on Ebay for about $75. We then pressed in some pre-made shafts of 3/4″ stainless hex bar with the ends turned down to 5/8″ round. We’ve gotten lucky 2 out of 3 times with the hex bar coming in a little over dimension, so it makes a nice press fit. But it occurs to me that if you heated the PE rounds to above 50c or so in a water bath before broaching, it would probably broach like butter and shrink down to make a nice press fit even if the hex bar was at nominal dimension.
It could be argued that we gild the lily a bit by using stainless hex bar for our shafts; our philosophy has been that we’re building stuff that’s going to last the rest of our lives, and we want the core of it to be rock-solid. And the time we’ve invested making it is substantial enough that spending a few hundred dollars on good materials seems warranted – hell, some people spend way more than that on bicycles or HiFi equipement. Anyway, once the PE was pressed on the hex shafts, we put one end in a 5/8 collet and the other end in a live center, and turned the OD to dimension (5″) – I bet we cleaned up the ends and took them down to length as well.
The fussiest part of the whole thing was getting the setup on the mill to cut the teeth on the drums. We used a manual rotary table, propped upright on the mill table so its axis of rotation was horizontal and along the long dimension of the mill table. The rotary table came with a tailstock, IIRC, and we had to fuss around with the test indicator for a while to get the shaft parallel to the X axis and to the mill table. Then we cut the grooves; I think we did a roughing pass all around, then once again with a finishing pass. The surface finish was acceptable, but not fantastic, as it was a cheap carbide router bit running at less than 2000 RPM. A little roughness is OK, but you want to try for decent finish, cuz UHMW is hard to sand smooth.
I recall we fiddled with the groove dimensions in Solidworks once we had them rough cut on the machine; it’s likely that the woodworking bits aren’t super precise to the dimensions that they seem to be made to (it’s rare that a hardware store router bit comes with an actual dimensioned drawing; for instance, is a core box bit really actually hemispheric? Anyway, the dimensions shown will work, and other dimensions could be made to work, so long as you lay it out in CAD ahead of time and make sure it gives a nice uniform crush everywhere on the tooth profile. Here’s a screenshot of the profile we designed:
There are a couple more details to the setup that are important. The (cheap, lubed-for-short-life) pillow block bearings we use are from McM; they mount to T slot extrusion on either side so it’s easy to adjust distances etc to get clearances and chain tension right. To set up the post crushers, we basically fix one drum and then slide the other drum up until it touches, then tap it the minimum distance back to get some clearance – well under 1mm is OK; apple seeds, stems, and other hard stuff seem to feed through by elastically deforming the polyethylene or springing the shafts a bit – you really don’t want anything hard that’s much bigger than an apple stem to feed through there though, or it will put a big gouge in the drums (or worse).
The chain drive is not shown in the images, but we drive the primary cutter drum and the left-hand post-crusher at the same speed from the same piece of bike chain. As mentioned above, the left crusher drum won’t drive the right one passively; it will make a horrible chunking noise if you try. So we use a separate piece of light 25 pitch chain to keep them in time – there are photos on the blog that show how this looks. On one of the drums the sprockets are keyed to the shaft, but on the other it’s just set screws, since you need to be able to manually set the phase of the one drum to the other and then lock it down. It works fine until the set screws vibrate loose; better would be a keyed flange bushing on the driven crusher’s shaft, with a circular slot arrangement that would allow greater precision and strength for locking in the phase.
Alternatively, if someone comes up with a more sophisticated (but still fabricatable) crusher shape that does self-drive, that would be brilliant. We designed the shape we use basically on intuition and what cutters we could find, and we pretty much just got lucky – I’m not sure how many more times we would have tried, since it was a couple late nights in the shop to make the first set. It’s possible that a proper involute with substantially deeper teeth would still work and still fling the pulp out of the grooves, so long as you were spinning fast enough. Sadly, few enough people have access to even a bridgeport; I don’t expect many folks can do their own proper gear hobbing.
The two bins of drops we bought from Brackett’s had set in the shade for a week, and required some picking through. The washing crew requests a pedal-powered apple washer for next year.
Um and Pops surveyed the scene while tub after tub of apples met their fate:
The post-crushers eject finely shaved and mashed apple guts. Except for a few loose set screws, the grinder worked well this year – note for next year: LOCTITE!
Rhonda and Nelle load apple pulp into the press. The overwhelming power of the hydraulic press resulted in some ruptured herniations last year, so we double-bagged this year and didn’t have any further blowout problems.
Holly and buster pedal the press:
Joshua and Jo run the press:
Cider flows (this is like 1/20th of the max flow when the stack is first pressed):
Filling carboys:
New this year was a bottling/drinking station. We bottled about 20 gallons of hard cider (minus some for the operators and assembled crowd) using the twin counterpressure bottling setup:
There were more kids than ever. There was a play tent set up in the middle of the field with a brand new air mattress for jumping on, which was promptly popped. 3/5 of the Gates family:
I finally got up to Five Islands for the first time since orchard weekend, and found the orchard completely overgrown with shoulder-high hay, with even the older trees half-buried. The orchard grass had gone bonkers, and the clover we planted last year was rank and knee-high, even taller in the two rows of spots where we put composted manure under the pumpkin hills. It is amazing the difference that a little effort seems to make in terms of the fertility of the soil – after the initial cultivation, we applied the amount of lime, phosphate rock, and greensand indicated by the soil test, and we’ve mowed a few times a year since, but basically that’s it – some of the compost etc that we’ve spread on the trees might be diffusing out between the rows, but we haven’t otherwise fertilized or amended in the orchard. At the beginning, despite correcting the macronutrients, the stand was thin and weedy, so much of the improvement must be due to the clover and vetch that we’ve planted as cover crops, and the frequent (but not too frequent) mowings.
The weather looked good Saturday AM and deteriorating thereafter, so I got right to it – I got a trailer and the small Kubota, and scooped up a load of composted chicken manure at the old homestead. I stashed the manure by the upper cabin and hooked up the four-foot Bush Hog. Mowing in the orchard was a trip – at first it was a sea of deep grass, then on the second pass a deep tunnel, and intense clouds of pollen lifted from the grass, turning the hood of the orange tractor yellow.
I also nearly mowed down a nesting hen turkey – she’s barely visible in this photo, taken from the seat of the tractor, but I mowed within 18 inches of her and she didn’t budge. Once I saw her I gave her a wide berth, leaving her a patch of grass for privacy:
Part way through the steering got really hard to turn, and I couldn’t figure out why. I went back to the barn and greased all the zerks on the front end, topped off the oil in the front axle, and filled the steering gearbox at the base of the column, which may have been dry. After that it was improved, but maybe not perfect – need to keep an eye on it so as not to do any permanent damage.
With the mowing done, I hitched up the disk, and Joanna used it to chop up the winter rye and weeds that had grown up in the strip where I failed to grow wheat and barley last year. I also hooked up the spring-tooth chisel plow (I have been calling it a spring-tooth harrow, but in looking online, the thing we’ve got looks way gnarlier than most spring-tooth harrows) to the larger tractor, since there were still a bunch of rocks and big roots, as it had been woods just 18 months before. Between us we got things pretty well turned in and smoothed out. It had started to rain by now, so rather than make things all mucky I went back to the east side and helped Dave clean out the stacks of scrap wood in the workshop. After supper it was just misting, so I borrowed a string trimmer and beat down the remaining tall grass in the rows, finishing basically at dark.
At dinner we sampled some of the goat cheese that Emily has been making, including the first wheel of aged hard cheese that she’d made, a colby:
Here’s the stash of aging cheese in their cellar:
It was raining again in the morning, so I helped Dave some more in the shop, then Emily and I spread manure in the orchard, making about 40 mounds for squash and pumpkins. Underseeding with clover seemed to work pretty well last year, so we’ll probably do that again – it would have been better if I had gotten it together to till the soil late last summer, and plant oats/clover: the oats would have nursed the clover and then winter killed, and the clover would have a beneficial head start, since it is slow to germinate. I also repaired the gate, which I caught with the corner of the tractor bucket, like a complete moron.
I had to leave Monday morning for work, and as I was going, Emily was filtering and chilling the morning’s milk, and starting another batch of cheese – this time a gouda:
Emily sends word that the bees are hard at work in the trees; the peaches are out and the apples soon to be. It sounds like most or all of the grafts on Nola’s 5-in-1 birthday tree are taking, and next chance I get I’ll turn over the stripe of orchard that’s going to host the pumpkins and squash this year.
It’s been a mild source of frustration that all these years we’ve been gradually expanding and improving the orchard, maps.google.com has maintained the same old images of that part of Maine, which dated from at least 2006, before we even started. I happened to look recently and was pleased to see that the images have been updated as of spring 2010; Joshua has been able to decipher the exact date (in May I think) that the satellite in question flew over, and and by the angle of shadows it looks as if it was mid-afternoon. Not for any particular practical reason, but it’s gratifying that all our hard work finally shows up:
(compare to before:)
It’s possible to make out the locations of individual trees in the old part of the orchard, plus the newground to the west and south; also the thinning for the Cornell maples in the woods to the west down toward the water. Also it looks like I had recently turned over the middle field; still not sure what to do with that this summer, whether to plant pumpkins on it or let the pasture mix from last year continue to develop – the buckwheat/deer buffet debacle pointed up the need for fencing around basically anything edible. Soil fertility, improving pastures for the new goat herd, and berry crops seem like good themes for this year. Also, I’d like to move toward a permanent fencing plan; the plastic-mesh-plus-electric is cheap and flexible, but it requires a lot of continuing maintenance. Once we know where things are going to settle out, I’d like to move toward woven wire as a lower maintenance solution.
We’re going to get apples this year! Well, four, to be exact, unless some of them drop. But they’re looking pretty good – three on the Roxbury Russet and one on the Yarlington Mill, which are two of my favorite varieties, so hopefully it’s a fortuitous start. We’ve had the oldest trees for a bit over three years now, and they’re not supposed to really start producing until 5 or 6 years, so it’s great that they’re getting started. By the books we’re probably supposed to pick them off for another year or two, but these are sturdy seedling trees that are way taller than I am by now, and they seem to know what they are doing, so I’ll let them go. If we had planted dwarf trees they would probably already be producing by now, but between the fine selection at Fedco and a bias toward the long-term view, we’ve decided to plant the slower-maturing standard rootstocks. If things go according to plan, we’ll be swimming in apples and cider a few years from now.
Early in the orchard project I resolved to give up large scale burning of brush, both to keep the carbon out of the atmosphere for a bit longer and to recycle the biomass into orchard soil fertility. Accordingly, last Sunday I planned a session with a large rented chipper, to reduce the large windrow of brush from the two rows of apple trees we added this spring to chips that can be used to mulch the trees and the perimeter fence around the orchard. These large diesel-powered wood chippers are fantastic and fearsome machines; the one we rented has a 14 inch diameter capacity. They are heavy and difficult to move, requiring a 3/4 ton pickup to tow them safely, and a sizable crew of energetic folks to feed them. I prevailed on my dad to pick up the machine Saturday afternoon and drop it off on Monday, and convinced some friends to come help feed the thing. Sunday morning I checked the fuel level, which was half a tank, so I poured in about six gallons of diesel, which took it to about 3/4 full, hitched the chipper to the big Kubota tractor, and pulled it out into the orchard. We set to work, and in an hour or so we had ground up the first big pile of brush into a sizeable heap of chips. We took a short break and shifted the chipper up to the next pile, which involved changing direction, to where we were sloped slightly to the right, where we had previously been sloped slightly to the left. We restarted the machine, and started chipping the next pile.
But after a couple of minutes, the machine abruptly started to bog down, and produce clouds of black smoke. It was clearly not right, so we shut it down, scratched our heads, checked the fuel (about half a tank), and tried it again (same result), and called the rental company, which was closing in about an hour – too soon to get it back and swap for another. They didn’t have any suggestions, so we cleaned up, pulled the chipper out of the orchard, and salved our disappointment by going fishing in the afternoon.
Monday morning the chipper went back to the rental shop, and shortly thereafter a phone call – the tank was half-full of gasoline! As soon as I heard that I went and checked the two cans that I had poured into the tank – the dregs in the cans was clearly diesel, by smell, feel, and color. And the chipper was operating normally with good power for the first hour or two – though in retrospect a quarter of a tank consumption did seem too much for the amount of chipping we did. To be double sure I checked the funnel I used, which conveniently was the sort that has screw caps on top and bottom to keep dust out – it surely contained diesel. Piecing the story together, this is what must have happened:
When we received the chipper, it had a half a tank of gasoline (or a gas-rich mix) in it. Before using it, I added a quarter tank of diesel fuel. I poured the fuel in fast and used a funnel with a long tube with a sort of nozzle on the tip, and diesel is significantly denser than gasoline. Though diesel is obviously miscible in gasoline, it must have flowed to the bottom with relatively minimal mixing and formed a pool there – otherwise it could not have run the machine for over an hour. There must have been enough mixing to cause an increase in fuel consumption; otherwise there’s no way it would have burned a quarter tank in less than 2 hours, but not enough to cause a noticeable loss of performance. But why did the machine stall so soon after we moved it? I think the key is in the lay of the land – by the fuel gage we had burned a volume nearly equal to the amount of diesel I added, so the layer of diesel (or mostly-diesel) would have been very thin. I didn’t notice which side of the tank the intake tube was on, but I would lay odds that it was on the side of the machine that was downhill when we started. Then when we turned it around the dwindling pool of mostly-diesel ended up on the opposite side of the tank, and as soon as we burned up the fuel that was in the lines and filter (which allowed us to chip a few armloads of brush in the new configuration) it started pulling the mostly-gas from the upper level of the tank, shutting down the works.
As best I can tell online, running a diesel on a mix of diesel and gasoline causes loss of power (check), dark smoke (check) and may cause excessive wear in the fuel system (since gasoline is much less lubricious than diesel oil). Hopefully we didn’t run the machine for long enough to do any permanent damage. The policy of the rental company is that the machine should be returned to the shop with the same amount of fuel as it left with, so it is likely that the previous renters got the machine with half a tank of fuel, used it for a while, and then stopped at a gas station on the return trip, and accidentally filled the machine back to half full with gas instead of diesel. Obviously we could be making this entire story up, and the rental company doesn’t have much basis on which to judge our story versus that of the previous renters (who would likely deny that they could ever have put in gasoline), but our family has a history of renting equipment from that shop without destroying it, and they haven’t made any effort to get us to pay for repairs, if that’s any indication. So, hopefully no permanent harm done, but getting the crew and the equipment together to finally finish the job isn’t something I relish.
Last night I put a couple finishing touches on the completely reworked apple grinder. Everything inside is polypropylene or stainless, except the anvil plate which is copper to preserve the sharpness of the cutters. The cutters are new, beefy 3/16″ stainless steel with machined serrations; I sprung for 440c knife stainless, which while in the annealed state (which seems to work fine) could be hardened to a high Rockwell C value if I knew somebody who could do heat treating.
I can’t wait to try it out!
Thursday night I bolted up the press for (hopefully) the final time, and yesterday morning I put a second coat of polyurethane on the wooden parts. I haven’t mounted the hydraulic ram assembly, but the press is within striking distance of functionality (we still need a bed plate and a press pan, but these can be bought/improvised quickly, and some larger grates – gotta get some maple from Maine for those) but today is a washout, so the plan is to work on the grinder upgrades.
