Tormenta 2 - Build Diary

[RogueTwoRobots]

If it's half as violent as air hockey games between you and the Big Nipper guys David, we're all in trouble!

[plargen]

i cant remember but if you said something about about burning out drill motor or knackering the gearbox but if it is to do with the motors i was thinking if you went for some 14.4v drill that had a 650 rpm output and over volted them to 18v you would only loose about 12 rpm and would put less strain on the motor

http://www.ebay.co.uk/itm/BRAND-NEW-GEN ... 4ced488dea

this is the same guy i get my 12v ones from and they seem better built than the last argos ones i got

[Ellis]

snip

Yeah, we're running the motors hard but the reason for them burning out is because of the gearboxes failing. Even if it were just the motors, I reckon those 14.4v ones are actually 12v motors overvolted. Doing the math, 550rpm (12v) overvolted to 14.4v gives 660rpm, give or take some. I'd say there's a fair chance those motors are actually 12v.

Also the build quality might well be better, as it's slightly more money for just the drill unit. You're not paying for the battery(s) nor charger. Interesting!

[plargen]

probably might be worth you looking at the gr2 lol, might be more cost effective in the long run

[plargen]

just wandering what the sprocket pitch is that your using for the weapon and if the chain has broken also if you know what sort of load its broken under or if its just because someone hit it (that's if its broken at all)

[Ellis]

It did break, but not due to the weakness of the actual chain, but the chain link that we bought. Broke twice. It's made of thinner, harder stuff, and under big loads it fails. This was fixed for us by Marien (thank you!) at MMM, but his fix (using the same/most of the bits that broke) failed again later on. I'd suggest you avoid a chain link and get a chain breaker tool.

As for loads, I don't know, it broke from a landing the first time and under stress from flipping something the second time. It's 6mm size chain from technobots. They have it rated at 300kg tensile strength.

[Eventorizon]

As it says 300kg in tension. As its a steel, in compression it will probably be much less.

[plargen]

just wandering if you know the max NM torque of the drill because if you times that by the chain gear reduction and then covert it to kg-cm and then divide it by the how many cm long the lifting arm is then you will know the max weight at the tip

then you just need a means of stopping it from lifting the back end up

only worked out how to calculate the weight because i'm looking at doing drill powered lifter design

[Ellis]

I don't really know anything about the drill as it was found next to the bins down the road! It can flip a FW comfortably, I'm just a bit pansy-ish with it because I'm scared of breaking something. Once the issues have been ironed out we'll do a maximum lift weight test and the torque should be backward-calculate-able from that.

Remember that you have to consider landing heavily etc, the weapon going full power one way and landing awkwardly on the arms in the opposite direction would result in massive stress.

Look forward to see what you come up with!

[plargen]

well so far i have a few different lifter arm designs the longest should be able to lift 40kg at the tip and and the shorter design about 70kg and that's using a 5-1 reduction from a drill it doesn't take into account the friction in the gears etc

might try doing interchangeable weapons