First time builder. please have a look and share your knowledge

[inq125]

Hiya guys, long time bot builder in the lighter divisions, mostly converting show brought R.c cars into ant & beetle weight bots in the local rc club. My last build was aged 16.. so over ten years ago, i now have two children, one of which whos bad about all things Fighting bots, hes been through ever episode of RW atleast twice now, and as you can imagine is keen for me to get building.

Whilst my 10 year old bot building self can appreciate a 5 year olds haste to build a robot wars worthy bot, the adult i am now knows theres a lot of prep and design before i can physically "build"


Im a carpenter joiner by trade, but have dabbled it electronics and metal work all my life. i know i have the skills, but im going to lack the finer details of wiring and amps ect.


Ideal i want a partial or full body spinner.

My initial drive is going to be made using balance board bits, and im still trying to figure out if i can easily adapt the preexisting control board to take its control from a receiver rather than the pressure switches it currently uses. Will need to look into it further!

i will at some point start a build in progress post, just wanted to say in the mean time.

hope anyone has anything they can add and advise me with,

kind regards, Dan

[typhoon_driver]

Hey Dan,

Welcome to the club. A full bodied spinner is an extreme challenge and I say that as the guy that drove the Typhoon bots. The forces and challenges involved are ten fold more complex than other designs. A robot with a spinner mounted is still difficult but easier in a number of ways.

Balance board bits won't cut it in the heavyweight division I'm afraid. If you want cheap motors there are a range of scooter motors on ebay around 800w to 1000w in various voltages that are cheap but have been used in robots like aftershock.

[Eventorizon]

Gary is very much correct about full body spinners, they are very difficult to build I'm afraid and are extremely dangerous to boot. However if you take your time you may well be able to come up with something that still meets the criteria.

On the subject or motors, Deathroll from Australia competed in Battlebots and used Balance Board hub wheels for drive. They were surprisingly effective for their cost, but once damaged you would need an total replacement rather than being able to change single components in a normal drivetrain. Check out their Facebook page for more info - https://www.facebook.com/TeamDeathRoll/

[inq125]

Thank you guys, well if its not a full body spinner then i think ill look into some sort of pneumatic ram or flipping arm, id like to go the razor route, but they all take an age to engage the piercing arm, having trawled through most of the bots in the robots section on here. im hoping for 4x4 drive, but other than that im pretty open to suggestion on weapons etc.

i dont suppose theres a wiring diagram anywhere for your average heavy weight? if not something i can copy/alter then something that'll at least point me in the right direction as regards to, motors, speed controllers, and the main one a weapons rig, or even a few different types of weapon rig.



What are the main issues you guys have faced when building a heavy weight? the weight?, and realistically what budget should i be working too. i cant afford hardox as new, but i can probably salvage some for key pieces from the local farms/scrap yard, for the weapons head, or side armour.



i guess what i really want is just a few effective reliable armament options..

as ever any help is massively appreciated!!


ill drop the balance board option, ive since taken it apart, and like you say the motors are housed (very cleverly) inside the wheels themselves. as wheels are generally a high priority target im guessing motors housed inside them whilst a space saver, is only going to cause problems down the line. like you both say burning them out and having to replace the lot is not ideal. so for now ill keep my eye out for some mobility scooter ones.



Equally if theres anyone reading this thread that wants to part with some parts, for cash ofc, please comment below, i have a large van, so collection isnt a problem.

once again, thanks all, dan

[inq125]

also trying to gauge weights of things, so if anyone has a wheelchair/mobility motor with and without the 90 degree gear box could you kindly weigh them and get back to me please. i have rough dimensions, but again would appreciate the exact sizes

also i have 10mm Hardox/Steel 100mmx100mm down at .79kg, so im going to use this to work out a rough weigh of my frame/shell,

can anyone recomened wether to other making a subframe, or shall i get a piece engineered? i.e cut, pressed and bent to create a solid base and shellin two pieces? or is it best to make a frame and go modular piece by piece?

its certainly not going to be revolutionary, more than likely for my first bot, a simple square/rectangle, wheels exposed both sides, with simple ram/screw lifting or crushing weapon. ideally something that runs of total electrics, as my pneumatic knowledge is little too none.



this may just be the ramblings of a mad man, but one who requires guidance from other mad men (or ladies)

[typhoon_driver]

I suspect a lot of your questions would be answered by the riobots manual (google it). The guys that built minotaur in the US put a lengthy manual together to help people get into bot building. A lot of it will be international in terms of components etc but it should give you a good handle on the basics. I've never read it cover to cover but have skimmed it.

As far as your first machine, if you plan to build a basic lifter with a drive train, which is a good starting point, then I'd probably go with the box section frame welded up with paneling bolted on. The modern way to build bots is to get a monocoque laser cut and then welded together but putting together a CAD design for such a machine requires a good bit of knowledge to get it right. A box section chassis allows you to easily add and remove things as you go along.

As far as scavenging goes, you might get lucky and stumble across hardox in it's professional form in a digger bucket or truck body being used for what it was designed for, a wearplate application. Either way steel in those uses is likely to be higher grade although it will probably be on the thick side.

The two main issues you'll come across in building bots is weight and money. There is never enough of either to do exactly what you want to do.

[Runsler]

The two main issues you'll come across in building bots is weight and money. There is never enough of either to do exactly what you want to do.

And time.
Don't forget the "a bot is never finished if the fight isn't in the next 24 hours, and even then not always"-phenomenon.



One more note on the actual build:
With a simple box-shape bot and first build, it is somewhat unlikely for you to get into Robot Wars, just because it is a TV-Show.
But not aiming for that in the first build might be a wise idea, so you can assume you'll be on other heavy fights. And as far as i know (might be wrong here, still a noob myself and only read stuff like that) there are currently no really spinner proof heavyweight-arenas in UK or europe. So there is a really good chance you won't fight vs. them.

You can try to put that into your design, too... way less front/side armor needed when there are no spinners around.
Maybe could get away even on a heavyweight with HDPE there, which is easier to work with (for some people, that is... depending on metalwork experience, but you could use woodworking tools for HDPE. just be ready for plastic everywhere. Used a padsaw on 20mm HDPE yesterday, and well... hard to cut a line you can't see because of the dirt you fabricate) and cheaper. Also needed much thicker than steel, but yeah... just want to give you an option to think about

[R9000]

As far as I know, Extreme Robots' new arena will accommodate heavyweight spinners, going on what I heard on the Inside the Bot Podcast Interview.

Edit: Here's the video confirmation: https://youtu.be/h0RfqVZoCnI

[inq125]

Thank you Gary, that pdf has helped so much in the past 24hrs, turns out i have high enough rated speed controllers anyway :') so bonus!

for now im going into prep mode, slowly gather bits until im happy to start the actual work, need to brush up on welding it would seem.

speak soon, Thanks again all, Dan

[Yatcatcher]

Hi

I know it's a pain, but the easiest way to build a chassis is to make it last after you have all the parts you are going to mount inside....

As to cheap (ish) options, 4QD aren't used much nowadays as the control isn't the best but give good reliable and cheap controllers with an optional RC control - work with low powered motors well. Also have current limiting, good with cheap motors!

For drive train, talk nicely to someone down your local Kart track for light weight wheels and tyres, drive cogs, chains, hubs, axles and bearings. All well able to work reliably with less powerful motors.

Motors, difficult decision. Tempting to go for American style Mag motors or Amp motors. Best budget motor is still perhaps the venerable Bosch 750 gpa motor. Run at 36 volts it has good power. The power is quoted in watts on a motor (the Bosch is rated at 750watts at 24 volts which is approx. 1HP). I think it's a good idea to buy a slightly better motor and not drive it so hard if you're on a budget so it will last.

Batteries - the advantages of Lipo seem to make them inevitable, just the savings in weight, the extra current and the small size. But they're not cheap. Gel lead acid are cheap but add 10 kg or so to your robot. They do limit the current too, but with cheap motors that's not a bad thing!

Spinners? The force you put into the opposition also goes into your robot through the bearing. Big motors, big controllers, big batteries, expensive materials. I'm sure it can be done cheaper but the successful spinners are big investment (time and / or money / machining) machines. Also if you're doing this with your kids, spinners are capable of huge harm.

Wiring? A very basic diagram attached.