Overvolt drillmotors

[stu]

Overvolt drillmotors

Yeah i have noticed, i used to use 100mm wheels, and then i swaped to 125mm for more speed, and thats when gears started to break. Even the teeth on the metal gears started to break off. I know the Big Nipper team broke off one of the Gear Shafts inside the gear box, but hey use quite big wheels. About 150mm diamter or more is it?

Mr Stu

[big_nipper]

Overvolt drillmotors

Stu, 6 Dia. Close enough

Great speed but without supporting the wheel shaft at both sides impacts kept bending the shaft and eventually it broke. The gearbox in blue seemed to hold up this time but it does have 5 planet gears on the last stage with the 30V drill motor (also Nutool) with 1200 rpm output speed. Pitty we couldnt get bigger wheels as this might have been able to keep up with the weaponless, err, ram bots.

[timothy_forde]

Overvolt drillmotors

well ill just throw in here that I use 4 12v drills on 24v in my feather with so far no problems at all useing 95mm wheels though it keeps the ibc warm lol

[andreww]

Overvolt drillmotors

I have also used 12 volt drills at 24 volts with the infamous red wheels that r 4 dollars each and screw straight onto the drills. They work a treat but u need speed controll and a little bit of slippage if necessary which saves the gearboxs.

[team_ireland]

Overvolt drillmotors

Not exactly over volting but does any body have any ideas on how to get the chuck off some drills.

I have removed the screw and i have tried a few methods. I have held the chuck in a vice and ran the drill. I have tried hand un screwing it. Any one else got any ideas?

Please help please
Regards
Ian

[Guest]

Overvolt drillmotors

Yeah, Id like to know that too. I used the chuck of the drill to make wheel hubs. Used an angle grinder to remove most of the chuck so I was left with the small threaded part and a plate with 3 hole in it that the jaws moved though. The only problem was that after a few fights the chuck jammed onto the drill shaft and I couldnt remove the whell or gearbox from the robot. Because it was between nights of a compition we pretty much destroyed the drill gearbox to remove it from the robot, so I could get the new wheel (and new drill too by that stage) in before my next fight.

[big_nipper]

Overvolt drillmotors

The way we do it is to take the screw out of the chuck first, an odd few need drilling out, and then put the chuck in the bench vice and rotate the handle very quickly. For a few this does not work so we short the motor wires together and try again, this works for us.

[armadrillo]

Overvolt drillmotors

Help Please.

I have just tested my drum weapon for the first time and the drill motor im using seems to get hot quite quick.

Ive got a 9.6v old style drill motor (Where there are proper gears that slide on a bar to change the gearing). I have used the original gearing from the drill to get approx 4000rpm(if my calculation are correct). Then using round belt drive to the weapon(see profile).

I am running the robot @ 12v so would be over volting the drill motor. When testing with a 12v battery the motor gets hot reasonably quickly.

Would speed control or some other device help this? Would a different motor be better? If so which type and how much would they cost?
Note: Money is Tight :sad:

Thanks for your help
Glen

[stu]

Overvolt drillmotors

Yo,
So your turning your motor ON/OFF If this is the case, the motor is near enough at stall when its given full battery power to start the drum spinning. I would advise the use of a speed controller and start the drum up slower than giving it full voltage which will heat the motor up alot. What might be perfect for you is a 30amp Electronize Speed Controller from Technobots would sort that out. Even a 15amp might do it, but would recomend a 30amp to be safe as they can deal with drill motors at stall, not sure on the 15ampers.

Kind Regards,
Mr Stu

[armadrillo]

Overvolt drillmotors

Yeah that was my train of thought as well Stu.
I will be getting some 30A Electronize for the drive after Crimbo anyway(providing i get enough cash for xmas) so 1 extra wont be too much difference.

Cheers

[geoff]

Overvolt drillmotors

Im not sure if I agree with the great Mr Stu (Sorry Stu!)on this one. You need to off set the extra weight of another speed controler against a simple on/off switch. He is quite correct about a momentery dead short (although its not a true dead short as the motor does have an inpeadence all be it a low one and the load reduces very rapidly as soon as the motor starts to turn) We have tried it both ways and experience shows that an on/off switch wins every time. We pull (in theory) around 110A on start up but that is for less that 1/4 second and if you do the maths that produces so little extra heat as to make no diference over all. What does matter is how hard the motor has to work to keep it all spinning. That of course is down to things like gear ratio, bearing and drive train resistance and overall motor power.(make sure your motor is powerfull enough for what you want it to do)
A speed controler will be a little kinder to your motor, but you will increase the spin-up time and you have the extra weight of the controler. So you need to ballence all this against a faster spin-up time and a hot motor!
Your choice!

[stu]

Overvolt drillmotors

The weight of a speed controller of 200g aint that much. LOL. But fair play to be honest. But like you said, its nicer on the motor after all.

But i thought once the thing is spinning - it needs effortless amount of power from the motor to keep it there. yeah true the motor is not in dead short, but it may as well be. LOL. Poor thing.

But also drill motors get mega hot anywya Glen, nothing too much to worry about though mate.

Mr Stu

[team_ireland]

Overvolt drillmotors

But i thought once the thing is spinning - it needs effortless amount of power from the motor to keep it there.

Stu thats true in a well engineered bot where everything is on bearings etc but if its just metal on metal then it will take alot more to keep it up there.

Regards
Ian

[geoff]

Overvolt drillmotors

Just an amusing thought....If you can engineer a bot with no bearing or drive train resistace...patent it quick, then retire on the proceeds!!!

[knightrous]

Overvolt drillmotors

Sounds like a job for mag lev bearings!