Donovan N.

Ok, the other day I sent out a message to a local Technical College asking if they would be interested in making me a set of billet rotors, and It turns out they seemed very interested since it would fit their CNC milling curriculum very well. But they did have some concerns about pattent rights for billet rotors once I mentioned that Mazdatrix and E&J had designs in the works. So I need to ask anybody who has seen either of the two companies aftermarket rotors in person If the companies had mentioned anything about copyrights and/or patents?

Any info you guys have would be greatly appreciated since this would be the most important hurdle of this project.

Here is what I wrote to the school:

To Whom it may concern

Hello my name is Donovan Ness. I would like to propose a personal project that I have that I think would be a very good project for a student if the school would be interested. Let me just say right off the bat that I am in no hurry for this project to be completed, but I would like to just get an Idea if this is something The School would be willing and/or capable to do. The project would be to make a rotor assembly(equivelent to a Piston and Connecting Rod in a conventional engine) for a Mazda Wankle Internal Combustion Engine. The reason I think this would be a good project for a student is that It would require design analysis in 3D modelling software and depending on manufacturing processes, the use of Stereolythography, metal casting, 3 axis CNC milling, 5 axis CNC milling, TIG welding, Electronic Discharge Machining, and plating/ ceramic Coating Technology. I have three possible processes in mind.

The possible processes I have in mind are:

1. A cast Rotor assembly- This would require Stereolythography to produce a negative "core" mold as well as positive mold, Metal Casting would be used to make the "Raw" rotor assembly, and 3 axis CNC machining would be used to attain final tollerances, the metals to be used would be either Aluminum alloy or (Depending on material cost and logistical capabilities) Titanium.

2. "One piece billet Rotor"- This would require 5 axis CNC milling (this would be needed to hollow out the internal structure of the rotor assembly), and 3 axis CNC milling to machine various blind holes and grooves. The material used would be 6061 T6 Aluminum

3. "Two piece Billet rotor"- This would require the use of 3 axis CNC milling and TIG Welding. The CNC milling would be to remove material from the internal structure of piece "A" as well as various blind holes and grooves. TIG welding would be used to permanently afix piece "B" (which is essentially only a face plate) to piece "A" to close the rotor assembly. The material to be used would be 6061 T6 Aluminum.

The only logistical problem I can think of would be that the rotor would need a few 0.7 mm (0.028") grooves machined into the front and rear faces, Now I am not sure that there are End Mills available that small for CNC Milling, which is why I mentioned Electronic Discharge Machining earlier, but again I am not sure if EDM is meant to be used to cut to specific depths or for lack of a better description "through all" of the material. I also mentioned the use of Plating/ Ceramic coating technologies, This may be required for pieces being made from 6061 T6 Aluminum depending on stress analysis data, which all the supporting maths are readilly available online.

Now I realise that the whole process from 3D modelling to final product could take quite a while to complete which is exactly why I believe It would be a good senior project which a student could use as a demonstration of their engineering/machining capabilities, I would even be very willing to provide feedback to potential employers of the student once the part is in service in a functional engine.

RX-Heven

iTrader: (1)

Why don't you ask MT and E&J?
I'd steer away from the 6061. It would be great material for the sake of refining the machining process because it is easily machined and cheap. MT did not have great testing results with that aluminum due to problems with thermal expansion and tolerances needed. This is one of the reasons they moved away from 6061 themselves and towards titanium.

Not sure about the E&J rotors though.

The guy who designed the 12-rotor engine is considering doing aluminum rotors, though in 7075 iirc.

Donovan N.

yes, after reviewing SCCA rules last night I realised that I have to use a ferous material anyway so I will probably go with a chromoly steel with inductive heat treating for increased wear resistance. But more importantly The school seems to be worried about copyright infringement.