Ich habe mal ein Video auf youtube gesehen (leider weiß ich nicht mehr wie es hießt oder von wem es ist) da hat der Youtuber Zahnräder aus verschiedenen Filamenten mit mehr als 30 tausend Umdrehungen getest. Ergebniss fasse ich jetzt hier nicht zusammen. Ich kanne nur sagen das wenn das Getreibe gut gefettet ist alle Filament weit über 2min durchgehalten haben. Er hat die Test dann immer abgebrochen, aber ich denke da es kaum Abnutzung bei den gefetteten Getrieben gab, Alle Filamente deutlich länger durchgehalten hätten. Als pack dein Getriebe in ein gehäuse und Fette deine Zahräder dann solltest du keine Probleme mehr haben.
Gruss der Garfield
I once saw a video on youtube (unfortunately I can’t remember what it’s called or who it’s from) where the youtuber tested gears made of different filaments with more than 30 thousand revolutions. I won’t summarise the results here. I can only say that if the gear is well greased, all filaments lasted well over 2 minutes. He then always cancelled the test, but I think that since there was hardly any wear on the greased gearboxes, all filaments would have lasted much longer. So put your gearbox in a housing and grease your gears and you should have no more problems.
I think experimenting with gears can be a lot of fun, but I can’t see 3D printed gears from PetG or PLA last long enough in this circumstance. I know you most likely already have the motor and therefore need a reduction, but I think a direct drive would simplify your life a lot. You can use bearings for the axles but almost by definition there will be friction between the teeth. And plastic used for 3D printing is designed to melt easily where plastics for gears ideally aren’t melty
That was V27 and the diodes threatened to blow along with the motors, which draw 20 amps from a 15 amp max battery. I would like to learn how to implement bearings though. Is it between the shaft and base?
If you stick the small gear directly onto the motor shaft it doesn’t need a bearing. The big gear will benefit from it though, so yes, you would put a bearing in-between it’s axle and the base. The base can be press fit and the axle depends on what kind of axle you have. Ideally the axle is connected in a fixed manner to the inner ring of the bearing but at this scale I don’t think it’s absolutely necessary.
Depending on the kind of bearing it’s even advised to have a double bearing on the axle to fully constrain it
I have quite a few radio control cars, planes, helis, and quadcopters that are good for very high speeds (my fastest car maybe 75MPH, plane somewhere north of 140MPH. Helis are slower. But I have a “speed” quadcopter I put together that’s capable of about 120MPH). The only time I’ve ever had anything catch fire, it was because a motor was stalled. Motors pull much less current when they’re turning than when they’re stalled. They are built with a design assumption that they won’t be overloaded this way. So almost any motor will smoke if you leave it powered and don’t let it turn.
Note the mechanical forces on a gearbox for a car traveling at high speeds is significant. I doubt a 3D printed gearset would survive. I’ve stripped metal gears… 20MPH shouldn’t be that much of a problem.
Did the gearbox turn freely by hand before you powered the motor?
You say 10000RPM motor but you don’t say what voltage you used. How big is the motor? Less than 10mm in diameter or larger than that? The power a motor can handle is highly proportional to its size. You might have just picked too small a motor, or you chose one with too high a “KV” (the RPM/volt speed constant). A motor with lower KV has more torque for the same current, at the cost of a lower RPM. But you can compensate for that with gearing.
Generally speaking, that’s valid. But some smaller “hobby” motors are sold based on their nominal RPM at 3.7V (the average voltage of a 1 cell Lithium Polymer battery). I most often see these advertised as something like 10000RPM or 13000RPM instead of just specifying the motor KV. Can’t say why, it just is…
Btw, my end product isn’t just any RC car… I have also obtained mini turrets for the top, a 6-axis IMU, and will soon mount a flamethrower on (I like fire).
rc
