Spell check for the above post please
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https://www.halfdonethings.com/

Yeah i've done the sums, and your right, its going to be just as expensive to buy the bits, as it would be to buy the kits of the electrozine kits, so thats the way i'm leaning at the moment.

I can see that the thought is very much don't do it, so i will most likly buy the electrozine kits. But thanks for the help and advice.

I will probably come back to it at some point, and see if i can do something, but to get a first bot up and running it isn't economical

I've heard drill motors are good. But are they fast and powerful enough for a featherweight rammer?
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It seemed like a good idea on paper...

Drills are perfectly fine for rambots.

You have a bunch of models to choose from:

- 18v 550 RPM
- 18v 900 RPM
- 14.4v 550 RPM
- 12v 550 RPM
- 9.6v 550 RPM

Those are the general voltage/speeds of drills you can pick up for $30 or less...
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https://www.halfdonethings.com/

i was thinking of a cheap way of making a variable speed controller because the drills im using do not have variable speed triggers and this is what i came up with
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WHEN YOU GO TO COURT YOU'RE TRUSTING YOUR FATE TO TWELVE PEOPLE
WHO AREN'T SMART ENOUGH TO GET OUT OF JURY DUTY

what do u think
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WHEN YOU GO TO COURT YOU'RE TRUSTING YOUR FATE TO TWELVE PEOPLE
WHO AREN'T SMART ENOUGH TO GET OUT OF JURY DUTY

I'd bet the pots would overheat uber fast, that's just a complex variation of a mechanical speed controler, the old versions people used to use in rc cars. I think big Al uses this, but has trouble with it catching fire and such...
On a similar note, im developing a cheap esc for my lightweight... will have some more info on it soon, it involves aspects of both el bravo's, AND vertex's awesome speed controler.
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That will work only for *very small* motors. Big ones will smoke your pots

The problem is, the resistance of the Potentiometer dissipates unwanted power as heat.

So, if for example your 12v motors would normally use 20amps at full-power (240 watts), and you want to reduce it to half, then you need to get rid of 120 watts worth of heat.

Imagine your potentiometer glowing brighter than a 100 watt light bulb and you will get the idea.

PWM Electronic Speed Controllers work by pulsing full-power at the motor with variable timing to control the speed. That way, any unwanted power is never sent to the motor..

When using resistors, the power is still drawn out of the battery, it is just burnt up as heat before it gets to the motor. Not very efficient for battery life either since any power you dont use is still being consumed/wasted.

Thats why resistive speed controllers are only effective for very small motors.
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I want a valve based ESC, no pesky smoke to worry about then. And it'll look cool. Cmon if they can make a mercury vapor arc rectifier take 10's of thousands of amps..... ;->
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Mechanical engineers build weapons, civil engineers build targets

Interesting Idea.

I've been tinkering around with Valves recently (Nixies and DekaTrons), but I dont know anything about high current switching with valves.

I imagine it wouldnt be easy, since stopping an arc without something to interrupt the power supply is difficult. What do the tesla coil guys use ? Still rotary spark gaps ?
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Great minds discuss ideas. Average minds discuss events. Small minds discuss people

You wont to talk to the coin squasher guys.

Jake remember we were talking about that back at PnP a while back lol.
I still don't know what's the problem with people buying a beetle esc, they're cheaper than most rc car esc's and are a one off thing (unless you're a n00b and blow it up first off)
... glen XD
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least i havent lowered myself to completing a beetleweight xD

vacuum tube esc would be cool. "give me 5 minutes to warm up my controller" lol
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angus different type of valve lol.
We mean the old style things that look like light bulbs.
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Mechanical engineers build weapons, civil engineers build targets

The tesla coils and coin crushers are run from capacitors so they don't need to interrupt the current - it drops to zero all by itself.