Team Thrifty /Fifty Build Diary for Bitza

[harry hills]

Re: Team Thrifty /Fifty Build Diary for Bitza

i just subscribed

[Anttazz]

Re: Team Thrifty /Fifty Build Diary for Bitza

...it got a good beating from LH at the 02 (could have stopped when you got through the armour!)

Thats for beating LS4

[PJ-27]

Re: Team Thrifty /Fifty Build Diary for Bitza

Haha, maybe!

[PJ-27]

Re: Team Thrifty /Fifty Build Diary for Bitza

The plans are pretty much set for Bitza 2.0, although we won't be able to start building for a few weeks.

It'll be an invertible vertical spinner. Same Bitza design and same motto (bits of this and bits of that), but could probably do with some spinner advise!

For the spinning weapon we plan to use a heavy disk with wide teeth, mounted in the scoop.

[PJ-27]

Re: Team Thrifty /Fifty Build Diary for Bitza

Trying to figure out if our 15a Electronize's are going to be up to the job with our new (plans) for 22.2v Li-Po's and 24v drill motors.

What sort of wottage are drill motors? My thinking was around the 75w mark (for the bigger (jumbo) 24v motors.)

By my calculations that works out about 6a continuous draw? Seems very low....

[ewan]

Re: Team Thrifty /Fifty Build Diary for Bitza

Depends what kind of wheels you're running/amount of accelerations & decelerations as to average current. If you're just running two drills at under-rated voltage then they'd probably be up to the job though

[jonny]

Re: Team Thrifty /Fifty Build Diary for Bitza

you could probably sell the 15 amp ones on here for £50 and then spend another £30 on 2 30a ones if you decide you need more current

[typhoon_driver]

Re: Team Thrifty /Fifty Build Diary for Bitza

a 24v drill on 22v should be ok on them. I've run 12v drills on 24v through an electronize without issue before. Granted that was with 100mm blue wheels. If you're planning on running the big wheels in bitza, unless they're not grippy at all you might overdo it.

Of course, you could just do the external relay modification on the electronize and for the price of 4 30A car relays have two 30A controllers.

[PJ-27]

Re: Team Thrifty /Fifty Build Diary for Bitza

Is it really just the relays that are at a different rating? I may look into that.... Do you use the 15a ones in Boner?

Doubt I could sell them for anything more than what it would be worth for me to just keep them. If that makes sense.....

We are using big wheels again and we plan on removing the wheel slip issues, but they will be geared lower.

Guess I'll just give it a go and see what happens. Hopefully it'll be alright.

[PJ-27]

Re: Team Thrifty /Fifty Build Diary for Bitza

We need some sort of On/Off switch to control the disk in Bitza Mk2.

I liked Sam's idea of using a Pico Switch to run a high amperage solid state relay, since you get the radio control and can handle the level of current being drawn, but it's no very Bitza-esque and expensive in the end.

Can anyone think of any alternatives? I'm assuming car relays are a good bet, but controlling these by radio is where my thought path ends....

Cheers,

[typhoon_driver]

Re: Team Thrifty /Fifty Build Diary for Bitza

Just go for the radio controlled relay controlling a larger relay (you could use a 40A car relay for a few quid). Any other interface with radio will be more of a headache and less reliable.

The other way that jumps to mind would be to use a servo hitting a microswitch which powers the control side of a relay. I wouldn't advise this route as it's not a failsafe proof system.

[Laser]

Re: Team Thrifty /Fifty Build Diary for Bitza

servo and microswitch not recommended. Almost ripped my robot apart
if you buy a external failsafe or have a spektrum its fine

[PJ-27]

Re: Team Thrifty /Fifty Build Diary for Bitza

Good point about the failsafe side of things.....

I'll need to consider that.

[jonny]

Re: Team Thrifty /Fifty Build Diary for Bitza

on some txs and rxs you can program the failsafe position so you could make it so servo failsafed so that the microswitch isn't pressed.

[typhoon_driver]

Re: Team Thrifty /Fifty Build Diary for Bitza

I would still recommend the RC relay option. Not that much more expensive.

ALWAYS consider the failsafe and takes as many precautions as possible when dealing with spinning weapons.