Van Door Motor Disassembly

[EricH]

Originally Posted by ZehP

If the motors are allowed, then you are allowed to remove the worm gears.

That would be modifying an integral gearbox... Read the blue box, first paragraph.

The intent of this rule is to maintain the maximum power level for each Robot, yet still allow teams to modify mounting tabs and the like, not to gain a weight reduction by potentially compromising the structural integrity of any motor. The integral mechanical and electrical system of the motor is not to be modified.

Also note the second paragraph which may shed light for a similar motor class.

Note that for the Window motors and the AndyMark gearmotor, the gearboxes are considered integral to the motor, thus the motor may not be used without the gearbox.

[Tristan Lall]

Take this one to the Q&A. The 2012 rules aren't clear about what's integral and what's not. Furthermore, since you can bring in scrap motors never before seen, FIRST can't decide in advance whether such a modification is legal for a particular design.

Ask FIRST to make a blanket statement about what's modifiable (under the cited rule) and what's integral (per the cited blue box), to aid in the selection of motors. They just need to officially say something like "inspectors will operate with a strong presumption that motor gearbox modifications are permissible, unless they have strong evidence that the motor itself has been electrically or mechanically compromised".

But until that time, it's hard to answer with any certainty. The worm gear systems have been variously considered integral and non-integral.

[jason701802]

Even if it is legal, which it doesn't look like it is, it would be very difficult to do. I have taken the gearbox off of a van door motor previously to use with a different motor and I had to completely destroy the motor in the process. If I remember right, you would have to cut directly and all the way through the gearbox to salvage the motor.