This documents a build of a Category 0 3 point hitch for the John Deere 316 Onan, 318, 322, 330, 332, 420 and 430 tractors. This is Neil Koch's build for his 318. Here's the comparison of the stock rock shaft vs. a 3pt rock shaft. Here is the steel to make the upper lift arms. Use a 1" hole saw for the big holes. The steel for the upper lift arms is 3/8" x 2" The longer ones are 8" long, hole is 1" from end The short ones at bottom are 5 3/8" long.
The two above are for center link - 3/16"x2"x5" The large hole are for positioning on "round" part Cut through the center of hole, and will weld back together when positioned on rockshaft. The upper lift arms will look like this when finished. To make each one you will need the following: 1 piece 3/8" x 2" x 8" 1 piece 3/8" x 2" x 5 3/8" 1 piece 3/8" x 2" x 2 1/4" 1 piece 3/8" x 2" x 2 3/4"
Here is the upper lift arms finished, you can see the rounded hole at the end to fit on rockshaft. Here is a pic of the fabricated lift arms in comparison to the original 3pt rockshaft.
In the pictures above you can see the two pieces of steel for the center link. The holes drilled in the ends needs to be 5/8". Make sure to drill all holes before welding any parts to the rockshaft because it is much easier to get them in a drill press!! You still need to drill the holes through the upper lift arms as well. The tricky part is getting the lift arms mounted at the proper angle in comparison to the deck lift arms. Here is the stock 3pt angle: Notice how the rockshaft is positioned. This is what needs to be done with the non-3pt rockshaft:
Finally, here are some measurements for where these pieces go on the rockshaft: The tricky part use a 3/8" piece of steel to hold it up "just right".
The center link will be positioned "level" with the surface you are working on, like this: Here is a good way to check that tricky angle for the lift arms I was talking about earlier. Look carefully at the position of the small square in this photo of the stock 3pt rockshaft. Align the flat edge of the deck lift arm with the center of the hole on lift arm. Picture says it better:
So, using that as a guide, this is how I will position my lift arm on the rockshaft: Next step is to drill the 5/8" holes in the lift arms to mount the "upper swivels". The biggest concern is
the difference in the design of that part the cylinder pushes and pulls on. Notice that the 3-pt rockshaft has a straight slot, and the stock rockshaft has a curved one. How this will effect do the lifting range of the hitch is not know at this time. If mobility needs to be increased, then this area may need to be modified. Here are the upper lift arms and the two pieces of steel for the center link. Here is the rockshaft cleaned up to allow for a better weld.
Top view of the lift arm in place. Notice the use of the triangular magnets to help position things. Combined with a steel table, they help when two hands are needed. See how the orange one keeps the arm square with the shaft. The socket it there to space things...it sticks to the magnet. Everything tacked into place. Use the measurements above to find the placement of the lift arms. The one is easy because it goes in between the two pieces that the cylinder pushes on.
Welding the center link on after the arms have been tacked into place. Tack weld everything until everything is located. Remember, measure twice, weld once...or something like that! Here's another angle:
Here is a shot of fabricated versus factory 3 point rockshaft.. Notice how it is sitting on the table, and how the center link is positioned... level with the table.
Here is the almost final product, tacked together and ready to try out: Bolt to tractor to checked for clearances. Up
and "down" Next step is to pull it back off, weld all joints really well, and weld the "halves" back on that were a result of cutting through the big 1" holes. This should strengthen things. Also put the category 0 "swivels" in place in the upper lift arms. This will be tricky in an effort to get a good weld with good penetration. For every flat joint that is welded together, cut "V" out the joint in order to provide for more weld and better penetration. Johnny Products provides the Cat 0 stuff you will need for later in the project. http://www.johnnyproducts.com/jp_parts_htms/cat_0_3_point_hardware.htm These CAT 0 swivels came from a local Kubota dealer for $6 each.
Next weld all of the "half sections" back on that was cut originally so that the lift arms would fit on the shaft. Next the upper swivels. Here you can see the original one next to the fabricated one. You will need a CAT 0 swivel joint, and a 5/8" rod to connect it. The longer piece of 5/8" rod is 1 1/8" long. The short one is: 5/8" long. Those are 5/8" steel bushings (like washers) sitting between the rods and swivel.
Here is a close up shot of the original that needs to be duplicated: Weld the bushing or washer onto the end of each piece of rod. Welding the bushing on the end and then grinding it smooth will allow more surface area to weld the swivel joint to. This will also prevent it from accidentally welding the swivel to the inside of the lift arm itself. Here is one 1 1/8" long rod with the bushing welded on top. With the bushing welded on, you can put the rod into the pivot hole. One hole will get the 1 1/8" rod,
the other side is 5/8" length rod. Here are both short lengths of rod with bushings in place, in their proper pivot holes. The cat 0 swivel is positioned in between, ready to be welded into place. The 1 1/8" long rod sticks out almost 1/2" on the "outside" of the lift arm. This piece sticking out has a small hole in it. Weld those swivels in place and the rockshaft will be done.
Rockshaft completed and painted. Here's a shot of the swivel welded into place. Ground down some of the square corners and cleaned it up a bit.
Primed and some black paint!!
Here's a close up of that swivel all painted up. Next the lower lift arms. Each lift arm is 1/2"x2"x20" flat stock..
Thickness is 1/2" steel. The end with the chain bolts to the tractor. In the picture above, the piece in the center is unbent and uncut. From the right end, and at 6 5/8" made a mark, then another mark at 17 3/4". This is where the bends are. Then cut out a "round" piece on the end with a torch to accommodate for the round swivel to be welded in place. Here's another shot.
Both bends are actually the same angle, so in essence it will complete a 3 1/4" offset. The angle is 165 degrees or 15 degrees depending upon how you measure (as illustrated above, but I wrote "65" instead of "165"). To do this, bend a thinner piece of steel to the desired angle to use as a guide. Then clamp each lift arm in a vice, heated at the bend line with a torch, and then bend it over with a sledge hammer until the bend matched the guide piece. If you start with two pieces of steel both 20" long, measure and bend them the same, you can produce two very similar pieces Shown below is extra arms for more hitches. Weld the swivel onto the end. Shim the lift arm up off the table in order to center it on the swivel.
Just about ready to weld it on...no turning back now!! Here it is welded into place. These swivels allow for a good weld with good penetration.
Here are a couple of shots of the lift arms with the swivels welded on the end.
The match set!! Drill some holes in the lower lift arms to attach the lifting links, and weld on a small piece to attach the limiting chains. For the swivels - The package says that the producer is "TISCO". The main part number appears to be "B2226". This is what the package reads line for line (refer to the archive pic) (TISCO) Qty. 2 (p/n?) B2226 30537-E1 159-2226 Ball Joint Weld on Cat 0 5/8" Bore First thing was to drill the 1/2" hole in the lift arms. The hole appears to be 9" from the bend.
Time to build these lower attachment brackets. Some measurements.
Here is the smaller piece measured out. The holes are all 5/8" on these brackets: Comparison of home made bracket to the original.
For the attachment bracket that connects the rockshaft lift arm to the lower lift arm, these were found at the local hardware for $2 each. After some disassembly and cutting, they look like this.
After a little welding, a little bending, and a little reaming of the top hole to make the 5/8" bolt fit... Had to bend those brackets a little bit to make them fit just right. Here's a shot showing the lower lift arm, the "hardware store" bracket, and the upper rockshaft lift arm. You can just barely see the lower lift arm attachment bracket as well.
And now...(drum roll please)...finally...here is a shot of all home made components bolted up to the tractor.. Another view...
Still need to rig up some limiting chains and to pull everything back off, then primer and paint it. All the way down The lifting range is about 11" from all the way down to all the way up and will lift at least 170 lbs.
Here are all of the components of "Build Your Own 3pt Hitch": Costs: Steel: $48.00 Swivels: $6/ea. $36.00 Center lift link: $20.00 Paint/Primer: $ 8.00 Bolts/Nuts: $ 6.00 Chain: $ 2.50 Total: $ 120.50 "Building it Yourself...Priceless" All mounted up!