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Small Farmer's Journal
PO Box 1627
Sisters, Oregon 97759
Mon - Thu, 8am - 4pm PST

McCormick-Deering Potato Digger



McCormick-Deering Potato Digger

This material is taken directly from the manufacturer’s original operating and setup instructions, a booklet given to the new owners of this implement when first purchased. It is written as though you are opening the crate and assembling your digger. You are most likely not. But that doesn’t mean you can’t use this information to good advantage as you work to understand, restore, and use your good machine. LRM

Instructions for Setting Up
Remove all wires and arrange parts conveniently.
Oil all bearings and moving parts as you proceed and see that they work freely.
Bolts must be used in holes in which they are found, or in parts to which they are attached, unless otherwise shown.
The illustrations show parts to be assembled; these must be placed on the machine in the order numbered.
In the following instructions, wherever the terms “left” and “right” are used, it should be understood to mean from a position behind and facing the machine.


1. Connect shovel lifting beam (7038AA).
2. Secure connecting links.
3. Secure truck wheels to axles, placing a steel washer at each end of wheel hub.
4. Secure tongue, hammer strap and clevis to truck frame, placing the distance block below the channel.
5. Secure truck axle braces to truck frame and to tongue.
6. Bolt tiller link connections to arms of shovel lifting beam so that truck wheels will be parallel to tongue.


1. Bolt lugs to tire.
2. Bolt seat to seat support
3. Bolt hinges (7255A right and 7256AA left for rod link elevator or 7280A right and 7281A left for riddle type elevators) to main drive shaft bracket. Put bolts in place from the inside with retaining clip (7277A) and nut on the outside.
1. Secure vine turner rods and fender rod as shown. (See illustration. No. 3.)


2. Raise rear shaker to place and secure hinges to lower channels. (See illustration No. 3.) The rear bolts take shaker frame hanger, front.
3. Put tilting rods to place.
4. Put on vine turner crank drive chain.
5. Attach pitman shield, right.
6. Put on shaker drive chain.
7. Attach shaker drive chain shield.
8. Secure oil can holder to tool box. Bolt tool box to main frame beam, left. (See illustration No. 5.)



(Rod Link Type Only)

Bolt hinges to main drive shaft brackets. (See item 3, illustration No. 2.)
1. Raise extension elevator in place and bolt hinges to sides.
2. Fasten tilting rods into place and attach lifting spring.
3. Place drive chain over sprockets and adjust chain tightener.
IMPORTANT: Place chain on sprockets with hooks forward and slot side out, to run in direction of travel, as shown in illustration No. 7A.



To detach chain, bend to coupling position and strike light blows.
4. Fasten elevator side extensions, or potato deflectors, in place.
The stone deflectors are adjustable by means of slot provided in them. In order that the deflectors may function properly and do the best work to cam the stones outwardly, loosen bolts at slots and adjust the deflectors so the lower face rubs slightly against the chain.
Important: Clevis should not be left loose on tractor draw bar. Use washers provided and draw up with nut until snug, then lock the cotter.






Continuous Apron Attachment
7076A—Only enough elevator speed and agitation should be used to obtain good separation. Plain rollers should be used when soil conditions will permit, as the extra wide elevator gives greater amount of separation which lessens the amount of agitation required.
7704A—Slip sprocket. Should be used when extension elevator drive chain is used, to allow for slippage of elevator apron.
7065AA—Should be used when slight agitation is required.
7064AA—Should be used when medium agitation is required.
7373AA—Should be used when violent agitation is required
(See illustration No. 14.)

1. Disconnect both main and extension elevator aprons and attach aprons at upper side. Remove enough links (about eight) so that apron does not drag on the ground, and connect aprons at lower side as illustrated.
Note: Look for open link which is beveled at both ends.
2. Fasten support roller, complete, to lower sides of extension elevator.
3. Bolt rollers to extension elevator sides.
4. Remove agitators from tie rod and replace with rollers.
5. Remove the regular apron drive sprockets and replace with special sprockets.
Use nothing but high-grade machine oil or high-grade hard grease.
Oil frequently, particularly during the first few days, with a new machine. As a general rule, frequent use of small quantities of oil gives better results than large quantities used at longer intervals. Be sure the oil holes are free from paint or dirt and see that the oil gets down into the bearings.
It is well to throw the machine into gear and drive it around for a time before starting to dig. This not only loosens up the parts and works the oil down into the bearings, but affords the operator an opportunity to see the parts in motion and to become familiar with the various parts and their functions.
All bearings or moving parts are provided with Alemite hydraulic fittings and require oil regularly.
Do not use oil or grease on the bearings for elevator apron rollers or agitators.


Before starting the digger, thoroughly clean all the paint or varnish from the shovel. This is important.
The digger is thrown into gear or out of gear by means of the lever at the right hand side of the driver’s seat. This lever also regulates the position of the rear shaker and vine turner or extension elevator. When the lever is in the highest notch of the quadrant the machine is out of gear.
The pawl shifter lever links are adjustable and should be set at such a length that the pawls will be entirely out of engagement when the lever is in the highest notch in the quadrant, and will be fully engaged when the machine is thrown in gear.
The depth the shovel enters the ground is regulated by the adjusting straps on the lifting lever quadrant. The lifting lever is of the pump type and may be set to the most convenient position on the quadrant. The ease with which the shovel can be raised depends on the will of the operator, as there are four holes in the quadrant for adjustment of the straps.

Adjustment of Aprons
Aprons may be adjusted by adding or removing link.
As apron wears, links may be removed by disconnecting apron at open link, which is beveled at both ends, and removing links until apron clears ground. (See “1,” illustration No. 14.)
If too many links are removed, it will make the apron too tight. This will cause digger to run hard and cause catching of small stones at front end of apron.
In some stony conditions, it is advisable to set elevator lower rollers in the same position as when stone trap is used (illustration No. 20), but leaving the space taken by stone trap open. This allows small stones to pass around lower rolls and gives room for slack apron to go ahead without catching on shovel.
Where agitation is required, the agitators shipped with the Digger may be substituted for plain rollers and may be varied to suit conditions by moving them up or down on the elevator.
When the lower agitator is moved farther up the elevator, the position of the supporting roller underneath the chain should be changed correspondingly to prevent stones locking between roller and agitator. (See Illustration No. 17.)
Stone Deflectors and Flanged Rollers may be obtained through repairs. The Stone Deflectors are adjustable by means of slot provided in them. In order that the deflectors may function properly and do the best work to cam the stones outwardly, loosen bolts at slots and adjust the deflectors so the lower face rubs slightly against the chain.

(See Illustration No. 19.)
When the nature of the soil is such that no agitation of the elevator is desired or needed, the grate may be raised up and supported in a stationary position by means of two flat support (A) resting on axle.

(6-Ft. or 7-Ft.)
The position of the rear shaker and vine turner must be governed by conditions. The best results in rowing the potatoes, however, will be obtained by having the center shaker rods just touch the ground when the machine is set in a working position.
The vine turner fork crank is assembled in the upper holes in the bracket when the machine is sent out. A lower set of holes is provided and the crank should be used in the position where best work can be done under existing conditions.
The shaker pitman crank and shaker crankshaft sprocket have two holes for pitman crank pin, one hole giving 2 1/8-inch throw, the other, 2 ½-inch throw.

Spotlight On: Crops & Soil

Barnyard Manure

Barnyard Manure

from issue:

The amount of manure produced must be considered in planning a cropping system for a farm. If one wishes to manure one-fifth of the land every year with 10 tons per acre, there would have to be provided two tons per year for each acre of the farm. This would require about one cow or horse, or equivalent, for each six acres of land.

Soil, Vegetation, and Acidity

From Dusty Shelves: Audels Gardeners and Growers Guide teaches us about soil acidity.

Planting Calendar and Other Diagrams

From Dusty Shelves: A 1943 calendar for seeding your vegetable garden.

Fjordworks: Horse Powered Potatoes

Fjordworks: Horse Powered Potatoes

This is the account of how one farm put more horse power into the planting, cultivation, and harvesting of its potato crop. Ever since we began farming on our own in 1994 one of our principle aims has been the conversion of our farm operation to live horse power wherever feasible. This has meant replacing mechanized tools such as tractors and rototillers and figuring out how to reduce human labor as we expanded upon the labor capacity of our work horses.

Cultivating Questions Ridge-Till Revisited

Cultivating Questions: Ridge-Till Revisited

Delay ridge building until early fall so that the cover crop on the ridge does not grow more than 12” tall before winter. The residues from a short cover crop will be much less challenging to cultivate than a tall stand of oats, especially if tangly field peas are mixed in. Waiting for the winterkilled cover crop residues to breakdown as long as possible before ridge-tilling in the spring will also make cultivation much easier until you gain familiarity with the system.

Cultivating Questions

Cultivating Questions: Follow-Up On Phosphorus

We like to think that the bio-extensive approach to market gardening minimizes the risk of overloading the soil with nutrients because the fallow lands make it possible to grow lots of cover crops to maintain soil structure and organic matter rather than relying on large quantities of manure and compost. However, we are now seeing the consequences of ignoring our own farm philosophy when we resorted to off-farm inputs to correct a phosphate deficiency.

Carrots and Beets The Roots of Our Garden

Carrots & Beets – The Roots of Our Garden

from issue:

Carrots and beets are some of the vegetables that are easy to kill with kindness. They’re little gluttons for space and nutrients, and must be handled with an iron fist to make them grow straight and strong. Give the buggers no slack at all! Your motto should be – “If in doubt, yank it out!” I pinch out a finger full (maybe 3/4” wide) and skip a finger width. Pinch and skip, pinch and skip, working with existing gaps and rooting out particularly thick clumps.

Fjordworks Horse Powered Potatoes Part 2

Fjordworks: Horse Powered Potatoes Part Two

These types of team implements for digging potatoes were the first big innovation in horse powered potato harvesting in the mid-19th century. Prior to the horse drawn digger the limitation on how many potatoes a farmer could plant was how many the farm crew could dig by hand. The basic design of these early diggers works so well that new models of this type of digger are once again being manufactured by contemporary horse drawn equipment suppliers.

Beating the Beetles – War & Peace in a Houston Garden

Blooming that is, unless the cucumber beetles arrive first.
And arrive they have … “At first I thought they looked like big, yellow lady bugs.” Paul said, “Then I looked…

Ginseng Culture

Ginseng Culture

U.S. Department of Agriculture Farmer’s Bulletin No. 1184 Issued 1921, Revised 1941 — The evident preference of the Chinese for the wild root and the unsatisfactory state of the general market for cultivated ginseng have caused grave doubts as to the future prospects of the industry. These doubts will probably be realized unless growers should strive for quality of product and not for quantity of production, as has been the all too common practice in the past.

Cultivating Questions Winterkilled Cover Crops for a Mild Climate Part 2

Cultivating Questions: Winterkilled Cover Crops For A Mild Climate Part 2

Finding just the right cover crop-tillage combination for crops planted the last half of June has always been a real challenge in our location. While surface-tilling mature rye and vetch in May works well for fall crops established in July and August, this cover crop-tillage combo does not allow enough time for decomposition and moisture accumulation for end-of-June plantings.

Cane Grinding

Cane Grinding: An Age-Old Georgia Tradition

from issue:

Most sugar cane is processed in refineries to give us molasses, brown sugar, and various kinds of white sugar. However, some South Georgia farms that raise sugar cane still process it the old way to produce the special tasting sweetener for their own food. One such farm is the Rocking R Ranch in Kibbee, Georgia. It is owned by Charles and Patricia Roberts and their sons. The process they use has not changed in the past 100 years. This is how it is done.

Cultivating Questions: Alternative Tillage & Inter-Seeding Techniques

Our intention is not to advocate the oddball living mulches we use with this single row inter-seeding system, but just to show how it is possible to utilize the between-row areas to improve insect habitat, reduce erosion, conserve moisture, fix some nitrogen, and grow a good bit of extra organic matter. If nothing else, experimenting with these alternative practices continues to keep farming exciting as we begin our twentieth season of bio-extensive market gardening.

Apple Cider Autumns Nectar

Apple Cider, Autumn’s Nectar

from issue:

While autumn’s beauty is food for our souls, autumn’s harvest provides food for our tables. Along with the many hours and days of canning and freezing our garden produce, harvest time also means apple cider making for our family. We have been making apple cider, or sweet cider as it is commonly called, for six years. Beginning slowly, the demand for our juice has resulted in a production of over six hundred gallons this year.

Prairie Grass A Jewel Among Kernels

Prairie Grass: A Jewel Among Kernels

from issue:

Years ago, my brother advised against plowing the patch of prairie on the back forty of our Hubbard, Iowa farm. “Some day,” he predicted, “that prairie will be as valuable as the rest of the 40 acres. We know how to grow corn; but that prairie was seeded by the last glacier.” Left untilled by generations of my family, the troublesome treasure has now become a jewel among a cluster of conventional crops on the farm.

Seed Quality from Two Perspectives

Seed Quality from Two Perspectives

from issue:

We are approaching this from a seed quality standpoint, not just a seed saving one. Saving seed is fairly simple to do, but the results from planting those seeds can be very mixed; without a basis of understanding of seed quality, people can be disappointed and confused as to why they got the results they did. Both the home gardener and the seed company must understand seed quality to be successful in their respective endeavors.

Farm Manure

Farm Manure

Naturally there is great variation in manure according to the animals it is made by, the feeding and bedding material, and the manner in which it is kept. Different analyses naturally shows different results and the tables here given serve only as a guide or index to the various kinds. The manure heap, by the way, is no place for old tin cans, bottles, glass, and other similar waste material.

Open-Pollinated Corn at Spruce Run Farm

Open-Pollinated Corn at Spruce Run Farm

from issue:

The old way of selecting seed from open-pollinated corn involved selecting the best ears from the poorest ground. I have tried to select perfect ears based on the open-pollinated seed corn standards of the past. I learned these standards from old agricultural texts. The chosen ears of Reid’s average from 9 to 10.5 inches long and have smooth, well-formed grains in straight rows. I try to select ears with grains that extend to the end of the cob.

Small Farmer's Journal

Small Farmer's Journal
PO Box 1627
Sisters, Oregon 97759
Mon - Thu, 8am - 4pm PDT