Tater digger/rock picker

[muddstopper]

Took digger for a trial run today. Not exactly what I had hoped for. A couple of problems I have ran into. First, I have 3 1/2in of stroke on my eccentrics. I found that with that much stroke, the digger will jerk the tiller back every time it strikes the ground. Second problem is speed of the digger attachment. I put equal size pulleys on the eccentric and the tiller shaft. I was worried that it might turn to fast, but I had to have a starting point so 1 to 1 gearing. The digger moves to slow with this arrangment. I feel like the slow speed is part of the problem with the jerking and stopping of the forward momentium. I plan on making a shorter eccentric, cutting the stoke about in half. I will also increase the size of the drive pulley from 3 3/4 dia to around 5. These two changes should speed up the digger and hopefully the shorter stroke should stop the jerking backwards of the tiller. Digger worked better with tiller in high gear than it did in low. But every time the digger attachment moved forward, it would stop the tiller. One contributing factor might be dry, very hard soil, but I think the mechanics are still the bigger problem. I will post a few more pics once I get the bugs worked out.

 

[CliffordK]

it would be nice to actually see one of the tater diggers in person.

Does it move forward and back, or up and down?
A moderate, fairly rapid vertical up and down movement of an inch or so would still give it a lot of digging action. Perhaps hinged at the front, and free to vibrate at the back.

 

[muddstopper]

The digger mover forward and back. It is hinged at the front and back. I will attach a few pics of what it currently looks like.

First pic is of the connecting rod. I took a piece of 1/2x2in flat bar and drilled a 1 1/8in hole, the same as the outside dia of the bearing. This proved to be a loose fit since I used a hole saw for the hole. if you look close at the edge of the bearing, you will see a small saw cut. I cut from the edge of the bar to the hole and then welded it back up. This tighten the hole until it was a press fit on the bearing. The other end I simply drilled for the 1/2in bolt I used for mounting the arm to the eccentric.

The next two pics are of the eccentric mounted and connected to the rocker arm on the digger attachment and the rest are just some pics of the digger and the rest of the set up.

 

[Millwood]

My digger "basket" moves laterally about 3 inches, but the nose "scoop" stays in contact with the ground and is kept in motion by link arms from the "basket" carrier. I made a short video of it working that will show the mechanics of it, but when I tried to post it here, it failed.

Send me your email address and I can clip it and send to you.

jlyph@comcast.net

 

[jarokoro]

I think the tiller does not have enough traction/power to pull it through the dirt, the potato diggers I am used to have a stationary digger spade with the shaker chain pulling dirt and potatoes up onto the shaker bed both the one and two row diggers were pto driven and pulled and the single row were ground driven.

I have seen similar one row diggers that were 3pt mount that was pulled by a small tractor

 

[OldMcDonald]

jarokoro, I have only seen fixed blades and bars in action (ignoring YouTube) but USA research showed that it was preferable to have the digger blade moving sideways too for these small diggers because the power required is reduced by up to, from memory, 70% rather than use a fixed blade - it was a substantial amount whatever it was.

 

[muddstopper]

UPS delivered my new pully's late yesterday so i didnt get around to putting them on. I will be doing so today. I also think my machine is going to be to lite to work properly, but I have some weights I will add to see if that helps. I am also looking for some bigger tires to see if that will help. Could run into more problems adding weights and tires in that I dont know how well the troybilt tiller gears will hold up to all that extra stress. Rain all day yesterday, and more rain called for today, so dont know if I will get to try it.

OldMc, what are your meaning when you say the digger blade moves sideways. Mine moves forward and back, but not side to side.

 

[OldMcDonald]

muddstopper, I am sorry but I cannot find the link. When klug was asking about a digger (the link to the thread is in your opening post) I began to think about a similar arrangement to pull behind my tractor for rock picking and did a lot of Googling. In amongst the many threads was a research paper from probably one of the US universities, that found a side to side movement of the blade, with the tractor moving forward of course, saved a lot of pulling power, and I think the saving was up to 70%. I spent about an hour at lunchtime today trying to find it again, but no luck.

I can see how it saves power. The forward/back motion is similar to using a spade by hand, whilst the side to side is a sawing motion, and, depending on forward speed, will be similar to using a knife to cut say cheese. It is almost dinner time here, and if my wife serves up a suitable cheese to go with the Port then I will try an experiment.

Back in the 1970s when I grew up to 10 acres of potatoes each year I had a single row digger that I pulled with my grey Fergie. Cannot remember the hp, but low. We planted in big ridges(hills) made with a Ferguson two row planter - me on the tractor and father and my wife on the planter, dropping a potato down the tube every time the bell rang. The blade on the lifter was fixed and had plastic covered rod in an escalator fashion that carried the crop to the back and left them on the ground. I had no problems getting right underneath the drills even in heavy ground, but the extra hp to a two wheeled machine no doubt made the difference.

Apologies for failing.

 

[OldMcDonald]

muddstopper, My dinner was on the table as I posted. I think I have read most of your posts, and consider you an intelligent person, so considering the non-scientific approach to my cheese cutting experiment, I believe you will be able to convert this to your needs for a potato digger. My son, an astro physicist of some international renown would no doubt scoff my approach, but first let us set the parameters.

The experiment was to determine whether a f/b attack on a piece of cheese (representing a potato hill) required more power than a sawing motion to cut off a slice of cheese. The attacker had first consumed a roast chicken breast and several vegetables together with a bottle of Palmela white from the Peninsula do Setúbal near Lisbon - excepting the half glass allocation for his wife. His wife, being a goodly sort of a woman who he married 42 years ago yesterday, had already laid out the courses to follow the roast. Part of these was a cheese from Soalheira, a mixture of goat and sheep milk, reasonably well matured and solid. The experimenter lacked the necessary equipment to determine its density.

The experimenter is not a particularly big man, 200+lbs, and about 5'10", old, but quite fit, so he did not attack the cheese with his full vigour. Nevertheless, several blows with the edge of a stainless steel plain bladed cheese knife (made in Sheffield, England) failed to create much of an impression in the surface of the cheese. Conversely, it took very little effort and very little time to completely sever a slice of cheese with a sawing motion of the same knife.

The experimenter reached the conclusion, after considering the matter over a glass of Fereira Ruby Port that a side to side motion of any particular instrument is more effective than a striking motion with the same instrument against any object to be cut. As a consequence of this decision he deduces that a potato digger with a side to side motion of the digging blade will require less force to be successful than would a potato digger with a blade of forward and backwards motion.

A single experiment I agree, but probably representative of the general application of force against soil.

As they say in McDonald's "Have a nice day".

 

[muddstopper]

OldMc, I suspect if I drink all that wine, I wouldnt care if the taters got dug or not. LOL. Now that you mention it, I think its time for some of my wifes Blackberry wine she likes to make every year.

Not sure how I would make my digger go side to side. Could cut the frame and turn it 90 degrees, but that would make the shaker drop the taters to the side of the machine. Probably have to redo the cutting edge as well. Dropping the taters or rocks to the side would be okay and make rigging up some sort of catcher on the side easier than mounting in the rear. I will continue to experiment with current setup for the time being since its already built. I changed the pulley ratio yesterday, but it rained like a cow wetting on a rock for 2 days, so I didnt do any testing. Speed of shaker is greatly improved. I still think traction is going to be a issue so I am searching for a couple of larger size tires to change out the ones on the machine. I have an extra set of the same size tires and wheels, Thinking about doing duals. Leaning that way actually.

 

[OldMcDonald]

muddstopper, since this is your thread, I feel I can add a bit more about wine. Wine is only about two and a half times the strength of beer. I used to make Blackberry wine when I was young. I had quite a few bottles when I went to Australia. When I came back my FIL told me most of them had begun leaking at the cork so he drank them. There was only one left and at 18yo it was truly magnificent. Best wine I ever made. Try to keep some for a few years. I have a proper cellar here, with the stone trough for foot pressing the grapes, vines too, but the wine I make is barely drinkable - and so is everybody else's home made that I have tried. Commercially made stuff starts at about the equivalent of $US1-30 a bottle, and similar price for 5litre casks. I drink a lot of cask stuff. I very rarely pay more than about $US3-20 for a bottle. Port is $6-50 upwards. I usually buy beer in half litre cans (I think that is fairly close to a US pint) and it costs about $US1-20.

I like the "cow wetting on rocks". It will not rain here again until October. Is pulling power not more of an issue than traction? Are you getting wheel slip now?

 

[Millwood]

OK, I'm a novice at spuds. This is my first crop on this ground. The digger I built is designed similar to the Spedo CPP-T single row unit, with some major changes so as not to tromp on Spedo's patent and get my hiney sued off. The one thing that makes it work easily is that the digger scoop stays in contact with the raised rows and moves in a 3/8 inch scooping motion with each rotation of the crank arm, lifting the soil and potatoes ahead of it, then shuffling everything onto the basket, with the dirt falling thru the separator rods and the spuds out the back and onto the ground surface. True, my digger is pulled by my tractor, but the effort is almost non-existent, with the drop in RPM about 150 which I think is more driveline need than forward effort.

Guess what I'm getting at is I don't think it matters whether it's a sawing motion or lifting motion that reduces the need for traction, it's just continuous motion against the soil, reducing the forward brute force requirement.

I have a quick, off the thread question for either of you. Since both of you are obviously experienced potato growers, I'd like to know if I did OK on my first effort? I'm averaging about 180 pounds of Burbank Russets out of each 125 foot row, or 1.44 pounds per foot. Bad, average. good?

 

[hawkeye08]

I'm not sure how to change what you have, but if you restrict the back and forward motion on the side opposite the driven part, it would in effect push side to side (if the pivot points allowed it).. perhaps it would end up being a twisting type motion, but at least not straight forward and back...

 

[muddstopper]

Millwood, I only raise enough taters to eat on, While I can remember planting spuds since I was a little fellow, I wouldnt classify myself as an experience tater grower, at least not commercialy. As for your adverage, I would consider it excellent when compared to my Kennebac's that we grow. Regional differences make a huge difference as to what type of taters to grow, while I have grew a few russets, they generaly dont do as good as kennebacs in my area.

OldMc, I kind of broke myself on drinking wine on my 21st birthday, For years i wouldnt touch the stuff. Most commercial wines, I still wont drink. For one thing, I cant stand the sulfates commercial wine makers just about have to use to prevent spoilage. we never use any sufites in our homemade wines. I prefer to simmer at 160F to kill off the bad stuff. Any hotter than that and you can set the pectin and the wine simply wont clear up. All of our wine sit for about a year before they are served. 2 years for Mead. I keep it in a small fridge in the basement. Every now and then we will have a bottle pop the top if left to sit in a wine rack. Nothing like getting up in the morning and trying to figure out where all that sticky stuff came from thats all over the floor. LOL. Not using any sulfites or Candam to stop fermentation has its risk, but I think it pays rewards when it comes to flavor. We mostly make a mucadine wine with wild muscadine grapes, but will make strawberry, apple, pear, cherry, blackberry when in season, and this year we are trying some watermellon wine. We make a lot of mead also when we can get the honey cheap enough. Funny thing is my wife and I dont drink all that much of anything, but our friends like to see us coming with bottle in hand.

 

[OldMcDonald]

Millwood, It depends on so many variables it is not possible for me to give you an answer - butyou can work it out for yourself. I have no idea about "normal" USA yields for the variety you grew. In fact I know nothing about US varieties at all other than I can buy Kennebec for planting, but I have never tried them. I am sure that some US Universities will have the information. I use them a lot when I want to know something agricultural about which I have little knowledge. Row length and yield are just the starting point. How far apart are your rows? Were the potatoes crowded by something else? Are they an early variety or a maincrop? Calculate an acre weight based on the info you have.

For guidance, UK average yields for a maincrop potato are now in the region of 18tons/acre (Imperial) which means a bit more for a US ton. Yields in other countries vary, but usually less. I would guess that anything over 12 tons would be considered reasonable for a maincrop. For an early variety - beginning to lift after about 10 weeks from planting, I would be very happy with 5 tons/acre. They are worth a lot more per pound, and it gets your customers for the year if you are growing commercially.

 

[OldMcDonald]

muddstopper, I enjoyed reading that paragraph. I am always interested in anything to do with wine.

I would never heat wine unless I was in Madeira. It kills the wine as well as any bacteria. If everything is clean then you should not need to use any sterilsers either. One year is a very young wine. Give them time, particularly something with a lot of tannin like blackberries. I suggest a minimum of five years, the other fruits do not need so much time, although something with high acidity like rhubarb, needs even longer for the acid to mellow. They used to reckon that rhubarb made in the birth year should be just about at its peak for the 21st Birthday. I hope your fridge is switched off and just used as a "steady temperature" storage. Do you use an air lock device on your fermenting vessels? Even after casking I have one in the top of the cask so that the wine can fully ferment out before bottling. In fact do you need to bottle? When making fruit and vegetable wines before I moved to Australia in 1979 I only made one gallon lots (the glass one gallon jars being known as demi-johns, but I do not know why) and just kept the wine in these, under an air lock, until they were ready to drink. I definitely do not fancy watermelon wine. Apples I think are best made into cider, but the others go extremely well with various spirits to make exceptionally tasty liquers. Try fresh ginger roots in a sweet white wine or cheap brandy too. Keep checking it every five minutes - seriously. Some gingers only need about 20 to 25 mins to put enough oomph into the wine or spirit. Others take a day.

 

[muddstopper]

Funny you mentioned the one gallon glass jugs. That is the size we mostly use, along with half gallon jugs. We do use an airlock. I dont like the big carboys, (5gal). They are simply to heavy to move around. Most of our wine sits under the kitchen sink while fermenting. I might have 10gal under the sink at any given time. The only wine stored in the fridge is wine that has been bottled. Maybe 6 0r 8 bottles at any given time. I dont like to use any clarifiers to help the wine clear, nor do we use any filters. We rack until clear and then bottle. With mead, this could take a year, sometimes more, before clearing. Fruit wines might take up to a year. I do use a commercial yeast, it seems to give a more consistant flavor than relying on the wild yeast. Everybody tells me I do wine making weird, but I make it to suit me so who cares. I dont see any of the nay sayers turning down a free bottle. My real specialty is applepie shine. even no drinkers can stop drinking it. Sneaks up on you to. LOL

 

[zing]

At first I thought your tiller would be too small/light to handle the vibrating action, but after watching a couple videos of the smaller ones in action it looks like it should do it. You are right about needing the bigger tires though. This video shows one close to your size (maybe a bit bigger, but still close and definitely shows that you don't need to have a CUT to run it) that works with steel paddle tires giving it lots of traction.
05092010025 - YouTube

Not sure if you want to put in this much work but here is a video that shows how you can make thoe tires yourself. Sorry about the guy spending the whole time with no shirt on. I had no control over that.
Изготовление грунтозацепов - YouTube

 

[muddstopper]

Wonder how much sunburn that fellow got and how many burn spots on his feet. I cant weld like that, I have a adversion to pain and suffering.

I had seen the other video before, but it was after I started building mine. I think instead of building steel paddle tires, I am just going to add dual wheels to mine. I have another set of tires and making and adapter for mounting will probably be a lot easier than making paddle wheels. One other thing I think I might or mightnot of done wrong is in the width of my digger. I sort of figured that since the tiller part of the original design was 22in wide, then the digger would work at that width. It might be a little wide for my light setup. Since i was more concerned with lifting rocks than I was potato's, when I started this project I wanted as wide as possible. For tater digging, you are just trying to get under the tater rows. My biggest problem now is finding time to finish and test. Its either raining or I'm working. I have changed pulley ratios and sped up the digging action by double. works pretty wicked in the shop, I just need to find dirt and not mud to put it in.

 

[muddstopper]

Got back to the digger build this wk. I had some old Steiner tractor tires laying around not being used, Just had to figure out how to mount them. The axle shaft out of the troybuilt tiller is 1in, the Stiener uses 4lug hubs. these hubs just happen to have the same bolt pattern as a couple of old hubs I had on the shelf. I took a piece of 1 7/8 shaft material, bored the center to 1 india to fit over the troybuilt axle shafts. I then turned the outside dia down to fit inside the 4lug hubs. A little welding, trueup the flange face on the lathe, and I now have big tires on the troybuilt.

Having a little slippage problem with the belt tensioner, I think I made the tensioner pulley mount a little to flimsy, it twists and lets the belt fly off. Still got a little tweaking to do, but my roundtoit seems to wander toward other projects