There is a lot of interest today in what used to be called "Truck Gardens"... maybe still are called truck gardens, but at any rate there are a lot of acreage gardens. In the "old days", before chemicals to control unwanted growth in a garden, it was necessary to cultivate in order to control "weeds" (definition of 'weeds' is any plant growth that is unwanted in the location where it now presides). We have now come full cycle and the marketing concept of "all natural", "chemical free", etc. and other similar terminology are selling points to indicate "healthier", "better taste", etc. It is not my intention to discuss the benefits, or the reality of such concepts, but if that is what is important in marketing, then it is necessary to "cultivate". Thus, our Riding Cultivator.
Garden tillers are great between the row to control weed growth, but what about "in the row" where our plants are growing?.. That is what cultivators do... they move the dirt into the row and around our plantings, and cover the unwanted plants (weeds).
Today's takeoffs of the Allis Chalmers model G are manufactured by Tuff-Bilt in Nebraska (price range $16,000 m/l). There are at least two other manufacturers with similar models - Tilmore Tractor in Ohio (price range $25,000 m/l), and Cleber,LLC in Alabama (price range $13,000 m/l).
THINK SIMPLE! - I believe that a model can be manufactured in a price range below these aforementioned and just plain garden tractors that really are not - "garden tractors"... at least they can not cultivate (at least to my knowledge). The engine size should be equivalent to 20 hp more/less and may be rear mounted, as example models noted earlier. The original Grand Haven was less than 10 hp. Today, a model with 20 hp more/less would be very cost effective and would be very practical for a wide range of applications, but primarily as a cultivating model.
The little tractor pictured (right & below) was manufactured by Grand Haven in Michigan in the 1950s and was promoted at the time as a "truck garden" tractor. This tractor was the forerunner of the Allis Chalmers model G (pictured above) and the John Deere model L (not pictured here).
The suggested design should be simplistic (as shown in the image on the left of a "homemade" model, as well as the images below of other "homemade" models) and would not necessarily include any power steering, nor lifting hydraulics (future option?). It could use manual lifts that would be "spring assist". Locomotion would most likely be from a hydrostatic transmission or hydro-gear wheel motors (by Hydro-Gear, Sullivan IL) ...not sure about the design of the braking system otherwise. The integration of the hydro-gear wheel motors also eliminates the need for a steering system and can easily be steered via the joy stick control* that is used by the hydrostatic transmission (hydro-wheel motors). This is an extremely simple design with a basic frame with a driver seat and control stick, free wheeling front gauge wheels, and a motor. Certainly more design would be required, but the overall design should be "simple". Riding lawn mowers, (such as the Country Clipper(TM) shown on the left - model XLT), could provide some of the basic design with their use of hydrastatics and hydro-gear wheel motor integration.
The wheel base width could be telescoping from 48" to 60" and that would accommodate 24" to 30" rows, and it could have some level of adjustment. The clearance should be 16 to 20" more/less.
The models pictured on the right, are new models produced by foreign manufacturers.
It should be noted that Asian and European Countries are very much influenced by small, "truck-garden" size plots, while America/USA is so focused on large scale farming that USA manufacturers often forget the ever-growing influence of small garden plots that often support Farmer's Market Outlets and locally produced garden products.
TerraTeck - I particlarly like the design idea of a "tool bar", as used by this model, for cultivator shovels' horizontal adjustment
Here are other models that have characteristics that would be beneficial on final design of a Riding Cultivator.
The models pictured below are "homemade" models...
Future options could be a PTO of some kind. The primary accessory equipment would be for cultivation, but also (at some point) a planter (lister ?) for seeds and maybe potatoes, plow, disc, other attachments as deemed practical.
(*): Control Box to be designed
NOTE: The images included herein are for reference purposes and not intended to be a "final" design.