The Milling Machine

The Mill with a rotary table with a fixture plate on top

The picture above shows a 6 axis build. Each axis is a movement, such the milling machine by itself has 3 axis, 1st axis allows the machine table to move left or right, the 2nd axis has the table move in or out, and finally the third has the quill move up or down. The quill holds the cutting tool, while the table with clamps hold the part to be milled.

When a rotary table is place on the mill table, you add the 4th axis. Place a compound slide, (XY) table on this rotating table and now 2 more axis are added. These axis are combined to create sophisticated milling maneuvers on your work piece. The final build I used a total of 7 axis.

This mill proved to be problematic, as can be seen in the photo above it is reinforced with 1/2″ thick iron flat bar to help control vibration. I even had to modify the mill by machining the dam thing since the vibration was so bad right out of the factory. As can be seen in these photos the machine is bolted to a cast iron table top, and this table is secured to a heavy 3x3x1/4″ angle iron frame, that also carries a heavy load of scrap metal on the lower shelve, all in my quest to keep the vibrations down by adding mass. After all this work I still could not get a smooth enough finish that I wanted on the milled parts. This was a contributing factor in stopping my attempt to machine this invention into reality. The highest speed of this machine is just too slow being only 1800rpm max. the cutting tools prefer speeds 3x greater.

With this mill being lightweight, and stacking equipment on it to achieve 7 axis of movement, I may have asked too much of it.

A compound sliding table that I was using proved to be out of square. Working with a machine tool and have it so out of true, and this being so unexpected and along with my inexperience proved disastrous. To overcome this built in flaw, I plotted on a spreadsheet the XY coordinates and drilled thousand of individual holes to machine my work piece. This was an incredibly tedious task, but I had come so far I couldn’t stop. Once I had milled this piece hole by hole and put it to the test along with the other machined parts. I realized the part that I spend hours and hours making needed to be modified. Yes I did swear. A good part of a decade had passed by this time.

This journey has been incredibly rewarding. To search for a solution that has never been found before, and finding it is an incredible rush. Although I was not able to build and assemble this drivetrain to completion, the parts that were assembled for proof of concepts along the way, lead directly to a design that obeys all the laws of math and mechanics.

Now showing folks that it works is my next goal.

There has been endless failed attempts to achieve this kind or transmission. Drivetrain engineers I don’t think spend a minute thinking about a solution, simply because simple mechanics and math proves no solution could possibly exists. If you wish to do a patent search on your own, for this type of drivetrain, the term variator will help.

When I first started I didn’t know this, but further investigation showed why it couldn’t be done and this was the show stopper. For some reason I couldn’t stop, ideas kept coming and I had to just follow these. Many ideas failed or the path taken discarded, but solution always presented themselves. This pattern repeated itself throughout the bicycle drivetrain. It is at this point we find ourselves here.

The Beauty of a Simple Idea

This drivetrain can be considered the holy grail for powertrain engineers, a nearly 100% efficient infinitely variable ratio, two dimensional chain driven drivetrain. There is no magic, and no breaking any rules. Sometimes the simplest of solutions are right in front of us. In this case there wasn’t. The amount of work involved was years long, and intense.

It took time to understand how parts interacted with each other in unique assemblies, and in a way that at no time is contact interrupted in this transfer of power from assembly to assembly in a continuous flowing manner. This continuous flow of torque is the same principle of why the bicycle chain is so efficient, and is carried forward with this design.

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