Schumacher Mi4

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  • Quote: Jesus christ, how often do you crash in one race?
    Fail!
  • Demo, what demo?

    I'll make sure to add you on


    Quote: the motor mount looks to be the same as the CAT, i have not had ANY issues with it. I DON'T WANT A HEAT SINK ON IT. the car is amazing looking even without a servo saver, in the past two years my Mi3 has worked just fine without one. The Fit and Finish of my Mi3's is perfect, no grinding, bending, sanding needed for assembly, it goes together flat and stays that way. I expect the same from the Mi4. With the improved bulk head design along with other changes I expect to have to add weight now. Great Job guys,

    Adam, you have my CC#, put me on the list and don't send it ground UPS.
    I'm going to Reedy so if you don't have any for sale yet, send me yours or Shawns demo model to put on display.
  • Quote: Think of moment of inertia and the flywheel effect,with off and on throttle reponse, then compare a brushless rotor and a brushed arm. I said that a rotor would be less likely to effect this clamp than a brushed motor would. Never the less I'm sure Shumacher has it all worked out.
    Yeah but, the rotor doesn't touch the clamp - the can does. And the only way to transfer torque from the rotor to the can is the magnetic force, which is simply the amount of torque the motor produces. A 17.5t has _way_ more torque than a 27t. I don't know the torque numbers for mod motors, so I don't know how the torque of a 17.5t compares to a 6t and a 4.5t. I suspect similar or lesser.

    The other way the rotor can put force on the clamp is if the drive train rapidly changes speeds: say you hit a wall and the tires stop. Now the rotor's inertia dictates how much vertical force there is between the spur and pinion, and that force is transferred and resisted by first the bearings, then the clamp. Now, I'll give you that the clamp is relatively weak in vertical force generated at the rotor compared to the traditional bulkhead, so hitting a wall could actually move the mount.
  • Quote: XRay's own top drivers are openly talking about their struggles with the car.



    The race he's talking about is LRP TCM, where the winning setup was basically identical to the same setup that was used to win every other big race this year. Does anybody really want a car that requires a dramatically different setup from one track to the next? Is that what luxury buys me?

    For a car that's apparently been hand-crafted by God himself, it sure has been a massive failure outside of a few foam tire races in the US. No worlds, no ETS, no TCM, etc. If you want to race the 5 guys still running foams, get the XRay. If you want to race rubbers like most of the US, and the rest of the world, there are clearly better options at the moment, optimization be damned. Face it, XRay makes a very good car with a high level of precision, and you pay for it. All that has meant precisely nothing on the track, both in the hands of the fast hobbyists a the pros.
    WHAMMY!!!
  • Until I saw Hayne's Mi3 I never really realized just how adjustable the schui is, you can really make the car have the geometry of just about any car on the market, and evey angle is adjustable by however thin a shim you would want. I am pretty sure within the first 2 weeks he had the car he had matched his pace from his type-r, both on foam and rubber, it certainly peaked some interest. The Mi-4 looks cool, it looks like a few things have been simplified like the arm mounts, I'm going to guess the mi3 parts will still fit if you wanted? If we end up getting another local track I'll be putting together one.
  • Quote: Yeah but, the rotor doesn't touch the clamp - the can does. And the only way to transfer torque from the rotor to the can is the magnetic force, which is simply the amount of torque the motor produces. A 17.5t has _way_ more torque than a 27t. I don't know the torque numbers for mod motors, so I don't know how the torque of a 17.5t compares to a 6t and a 4.5t. I suspect similar or lesser.

    The other way the rotor can put force on the clamp is if the drive train rapidly changes speeds: say you hit a wall and the tires stop. Now the rotor's inertia dictates how much vertical force there is between the spur and pinion, and that force is transferred and resisted by first the bearings, then the clamp. Now, I'll give you that the clamp is relatively weak in vertical force generated at the rotor compared to the traditional bulkhead, so hitting a wall could actually move the mount.
    But for all of us running the CatSx. None of us have had problems. And believe me, my car has taken some hard freakin hits LOL. And the motor has never moved place! I was a bit skeptical about it at first also, but once you have used it you get used to it.
  • Quote: Yeah but, the rotor doesn't touch the clamp - the can does. And the only way to transfer torque from the rotor to the can is the magnetic force, which is simply the amount of torque the motor produces. A 17.5t has _way_ more torque than a 27t. I don't know the torque numbers for mod motors, so I don't know how the torque of a 17.5t compares to a 6t and a 4.5t. I suspect similar or lesser.

    The other way the rotor can put force on the clamp is if the drive train rapidly changes speeds: say you hit a wall and the tires stop. Now the rotor's inertia dictates how much vertical force there is between the spur and pinion, and that force is transferred and resisted by first the bearings, then the clamp. Now, I'll give you that the clamp is relatively weak in vertical force generated at the rotor compared to the traditional bulkhead, so hitting a wall could actually move the mount.
    I'll make this simple for you, unbolt your motor from your car and hold it in your hand, now gun the motoro a couple of times and then hit the brakes. Thats the same thing that the clamp is trying to prevent. Now I have a similar clamp for a motor checker and it has a big thumb wheel to crank it tight, and the motor still rotates, so I don't a single screw will be anymore effective. BUT I'm sure that Schumacher has this worked out in some way that we can't see in the pics. Still a very nice piece.
  • Johnny W, i know what you are saying, but rest assured the one in my cat holds just fine. with the jumps, wash boards and general crashing, i haven't had a problem, If your motor as a after market sticker such as a "high velocity" sticker it will show signs of moving over time. My speedpassion motors haven't shown any wear issues. hope that helps
  • Also, for guys who are doubting the motor clamp, the two screws holding a motor within a conventional motor mount are essentially a clamp, but with a much smaller suface area than that of the schuey motor mount.

    There is ALOT of leverage and stress put on two little machine screws, yet they rarely move upon crashes and whatnot. As for the torque of the rotor and/or armature, the same applies with conventional motor mounts. The only thing different about the shuey mount is that its, well, different. If anything, the added surface area should hold the motor more securely and put less stress on the chassis, bulkheads, and motor mounts.

    Think about it, would you rather hold a broom horizontally from then end, or the middle? And If one where to twist the broom, which hold would be more secure?

    At least, that's my way of thinking things.

    A great move if you ask me.
  • AMain, I disagree with your post above.

    The issue at hand is the Mi4 motor mount holds the motor in via friction, as well as 2 screws clamping the motor mount to the bulkhead. In the conventional way, the motor can not rotate since 2 screws clamp the motor directly to the bulkhead are machined perpendicular to the torque vector.

    I personally think the Mi4 method will work fine, but as we all know screws do come loose during operation on ANY chassis. I would be more worried about the clamp loosening up and the motor torquing itself over and stressing the solder tabs and sensor plug.
  • Quote: AMain, I disagree with your post above.

    The issue at hand is the Mi4 motor mount holds the motor in via friction, as well as 2 screws clamping the motor mount to the bulkhead. In the conventional way, the motor can not rotate since 2 screws clamp the motor directly to the bulkhead are machined perpendicular to the torque vector.

    What's your disagreement then? Are you talking about torque from the rotor and or armature? Last time i checked, that torque would be applied directly to the motor mount, being that it is milled to allow the motor can to rotate along a certain axis to be able to adjust gear mesh.

    I don't get what you are neccesarily trying to point out.
  • All this talk of theory is bollocks.

    It has been tested by Lee Woodhams and Chris Grainer and neither have had any problems with the motor rotating.

    Same with the schumacher cat.

    Theory my arse!

    End of discussion.
  • Quote: What's your disagreement then? Are you talking about torque from the rotor and or armature? Last time i checked, that torque would be applied directly to the motor mount, being that it is milled to allow the motor can to rotate along a certain axis to be able to adjust gear mesh.

    I don't get what you are neccesarily trying to point out.
    you can spin the motor all you want, it isn't going to effect/affect gear mesh.
    the motor mount slides to do that.



    yea and what nick said
  • The motor clamp has been tested and run in the Cat development for the past year, the MI4 and it's clamp design has been tested for the past several months. Not one time in all that development and testing did the motor clamp "twisting the motors because of torque" ever come up.

    It hasn't been an issue, I've seen first hand it isn't an issue, stop over thinking the design and enjoy it instead, finally something different which is what everyone asks for, then they get it and everyone complains about it
  • Quote: He's on my poo list but I love him anyway
    Hopefully I will get off that list in the near future.

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