elobire's build thread

a couple of people wanted a update on my first robot so i thought id make a build thread.
this is what i have so far:
http://i639.photobucket.com/albums/u...e/PICT0006.jpg
not the nicest looking thing but it will do just for a test untill i get a welder.
i did make it out of aluminium at first (from a dish washer), but with 75mm wheels it wouldnt get any grip, so i bought some 125mm PVC wheels from robochalenge becuase the blue wheels where sold out. anyway, i couldnt be bothered to modify it for bigger wheels so i used some chipboard and other wood.
i might get a photo of the other chasis tomorrow if i have time.

even though it works im going to wait till i get another transmitter, the one i got is for a RC car, and doesnt have two foward sticks.
im also planning on making another before entering a compotion and getting some new batteries (i was adviced to but i was on a tight budget)
i might do more to it tomorrow, but im still undecided on what weapon to use, or what to do next.

well done mate looks like a nice simple setup for a first robot

im thinking about putting a axe on it, a disk would be too dangerous and somebody said i wont be able to take it to some events?
for the transmitter im hoping to get the planet 5:
http://www.galaxymodels.co.uk/detail.as ... 2|134#lift
is this the ideal one i should get? i only have up to £50 for the transmitter.

Yeah with a spinner you will only be able to compete at events run by Robo Challenge as theirs is the only arena that can safely contain spinners at the moment. With an axe you will be able to run at Roaming Robots and Robots Live events too.

The link you've provided is only for the Planet 5 transmitter. You would need to buy the receiver to go with it, which will probably cost ~£15 so that'd be right up at your total of £50.
Alternatively, there is the 2.4GHz 4-channel transmitter and receiver combo from Giant Cod RC for ~£26:
http://www.giantcod.co.uk/gianitcod-24g ... 03779.html

That is a basic-function transmitter/receiver, it will allow you to control your robot and has inbuilt mixing if you wish to have one-stick control, but features such as dual rates etc (commonly found on more expensive transmitters) aren't present but also aren't essential to the control of your robot so it would be a suitable alternative to the Planet 5 set.

http://www.elitemodelsonline.co.uk/Prod ... ET-MODE-II

There you go, with a reciever and under £50.

i might just go with the one from giantcod instead, looks decent enough untill i can afford something better.
done a bit of research on the axe, and a guide said to buy this chain/sprocket set: http://secure.oatleyelectronics.com//pr ... 2cefc40094

what i was wondering is if i can use one of the scooter motors that i bought for the robot drive but decided it was too complicated. the problem with them is that it doesnt have the sprocket for the chain on the motor, would i be able to buy a sprocket and attach it to my motor, to save me buying the one the guide told me to?

here is the motor the guide told me to get: http://secure.oatleyelectronics.com//pr ... 2cefc40094

the guide: http://www.robowars.org/wikka/ElectricAxeWeapons


im also hoping to get a welder for my birthday as well as the transmitter (i want a cheap transmitter so i can buy a decent welder), so once im done with the wooden test frame il start with a metal frame.

yeh

it depends what ratio you want ie how fast you want your axe swing compared to the motor speed

so that would dictate wether that kit would be useful (only had a quick look at the picture)

alex

I recently built an axe using this guide, although I am no expert the following two points may be worth considering.

Wood is no good for axes like this - it cant take the force and just splits, as I found out a couple of times.

Sprocket and chain do work I used one very similar to the one you are looking at (you can get them in the uk if you just ring up a scooter garage) and am pleased with the results - however I am thinking of changing to a geared system for two reasons, first the chain does come off quite a bit which is annoying and secondly it would pack more of a punch with a bigger gear reduction. From suggestions given to me I am looking at getting: Steel Spur Gear MOD 1.0 12 Tooth - Part No: 4710-012, Tbot Steel Spur Gear MOD 1.0 60 Tooth - Part No: 4710-060, Tbot Steel Spur Gear MOD 1.5 12 Tooth - Part No: 4715-012, Steel Spur Gear MOD 1.5 36 Tooth - Part No: 4715-036 (part numbers are for technobots).

Hope this helps

sorry for no updates, my internets been down.

anyway, the robot hasnt changed at all yet apart from some sections i made to tempererily hold the batteries. i havnt bought what i need for the axe or the transmitter due to internet problems either.
however i just got a welder for my birthday, so im hoping on making a metal chasis after testing it all out on the wooden one. my exams are also over next monday so i should have 2 months to make it.

one question though, what kind of metal do most people use?

Lucky, my parents won't let me have a welder as they think I'll blow myself/the house up :(

Steel, Aluminium and Titanium are most commonly used. Chances are you will have a stick welder and steel is used with them. Although but I have seen aluminium brazing rods (use a blowtorch) and aluminium welding rods (for a stick welder) that don't need any gas. Not sure if they're any good but if you don't want so shell out for a different sort of welder and gas and be able to weld ali and steel then they might be the way to go.

to weld ti and ali well you really need to know your stuff

steel is fine and a good point to learn from

im trying to learn how to weld better before i buy the materials, so far what i can weld is too weak for what i want.
i think the welder is a gassless mig with a coil thing.

im going to go look for some guides on the net as well, see if i can pick up any tips.
still havnt ordered the axe mechanism yet, i have to go to the bank first but i want to order them this week so they are here just after i finish my exams (monday).

MIG welding is the simplest form of welding and a good one to start out on. Best advice i can give is to first relax, find the correct distance from the material and then move the torch in a slow steady manner along the weld path keeping it that same distance from the material

Get Calum to help you out with welding, Im sure hes got a few spare pigeons.

Seriously tho Mig is nice and easy, Its harder to get a good weld with gasless mig than using mig with argon/co2 but should still be good enough for what you need. It can be tricky at first getting the right power and wire feed speed combination.
Make sure you have enough power to penetrate (thats what she said) then just play with the wire feed.
It would probably be easier sombody showing you if theres anyone you know close by that can weld.

yh i can sell u some pigeons no problem just pm me :P

whats a pidgeon?
also how do i connect the motor for my axe to the reciever, will i need another speed controller?

You will need some form of interface to allow the receiver to control it. Either a speed controller however I'd be more inclined to use a big relay activated by a remote controlled relay (dimension engineering battleswitch or similar controlling an automotive relay or bigger).

Others have wired up relay based axe systems in the past so they will be able to advise you on a suitable diagram (can't think of it off the top of my head atm)

is their anyone here who can draw me a quick diagram for it please?

Quote:

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Originally Posted by elobire

whats a pidgeon?

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lol, a pidgeon is a bird :rofl:

*what it actualy means in robot terms is a weld that looks slightly ugly/messy, but tbh as long as it holds the metal together its all good :mrgreen: *

does anyone have any suggestions for the relay and battleswitch?

just ordered the chain and sprocket as well as 2 flange bearings. just need the motor, battery and transmitter.
still need to decide how im going to controll the axe.

EDIT: do you guys think this battleswitch will work for the axe?
http://www.robotmarketplace.com/product ... TLSW1.html

when people say battle switch they mean the one you have linked to its a product brand if you like

and yes thats right but you will find it on technobots btw

Quote:

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Originally Posted by psycho_fling

when people say battle switch they mean the one you have linked to its a product brand if you like

and yes thats right but you will find it on technobots btw

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oh i understand now.
just a bit miffed when i noticed the VAT on technobots for the battleswitch was 17.5%, i guess thats what we get for voting in cameron.

No, that's what we get for living in a country where VAT has been 17.5% for quite a few years now :P
Now that Cameron's in, it will be rising to 20% from 4th January 2011.

*wallet goes and hides in corner*

:uhoh:

this ones cheaper...
http://web.me.com/robochallenge/Robo_Ch ... onics.html
and its english if thats ok

Quote:

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Originally Posted by Bodge Job

this ones cheaper...
http://web.me.com/robochallenge/Robo_Ch ... onics.html
and its english if thats ok

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thanks for the link. il buy it from robochallenge, bought stuff from them before.

Just a word of advice; a battleswitch turns something on and off (in some cases, such as yours, through a bigger relay). So that means you can turn your axe motor on (fire forwards) and off. But you need to return the axe so you will need another battleswitch to turn the motor on in the other direction (axe return).

Based on Technobots prices, a battleswitch costs £19 inc tax, so for two that would be £38. But they also stock a Doubleswitch, which is a dual battleswitch for £25 inc tax, saving yourself £13:

http://www.technobotsonline.com/doubles ... ay-8a.html

It is a double-pole, double-throw switch, which is needed to control a motor in a fwd-off-back manner, so connecting this up to two larger relays should provide you with the ability to both fire and retract your axe.

thanks, do you have any recomendations for 2 larger relays?

Can do, although using large relays for weapon control is an area that I've not really had to delve into yet, so another forum member will probably be able to make a better recommendation as to which type to get.

In order to get an idea of what relay to use, can you provide a link to, or some information about, the motor you will be using for your axe?

the motor i am using is this:
http://secure.oatleyelectronics.com//pr ... 2cefc40094

still havnt got the batteries for it yet, but im going to test it on the 2 12v batteries i bought for a similar scooter motor which i didnt use. their only cheap ones as i was short of money, so i hope to get a completely new set for the real robot.

This is not easy to see in this picture but the lift motor (red) for Cherub HW, is controlled by two relays 24v and 2 micro
switches operated by a micro servo on the throttle channel this seems to work fine and is quite cheep to do.

http://i569.photobucket.com/albums/s...g?t=1277483141

How you allowed for shipping and import tax on that motor buying from australia? I got mine for a scotor shop in the UK, the motors are identical and much cheaper then shipping them over

i cant really see from the photo how it works, do you have any other photos of it?

zoll, i havnt really considered the shipping cost yet, but i think il buy it from the UK instead.

HOPE THIS HELPS
I can draw the circuit for you at the next event if you want.

http://i569.photobucket.com/albums/s...g?t=1277547049

thanks for the photo. can you recomend a relay to use for this motor?:
http://secure.oatleyelectronics.com//pr ... 2cefc40094

Look at automotive relays. Something like this should do the job http://cgi.ebay.co.uk/24V-CHANGEOVER-RE ... 4150aa37d4

Hard to see if that one from eBay has a mounting point, but if not, you can get a similar thing from Technobots:

http://www.technobotsonline.com/24v-spc ... relay.html

I believe two of them would do the job. The only problem is though; these relays need 24V to activate the relay coil (which produces the switching motion). I don't know what the lowest voltage is that they'll operate at, but if you're running your robot at 12V you may need one with a 12V coil. Technobots used to stock them (they still show up on their old site) but don't seem to anymore. I'm in a similar situation as one of my speedo relays is dead in my robot and I'm out of spares so I'll see if I can find a couple of links to 12V ones.

EDIT: If you want six of them :lol:
http://cgi.ebay.co.uk/12V-40-30AMP-5-PI ... _849wt_930

well the motor was 24v so i assumed the machine will be run on 24v

found a 12v relay:
http://cgi.ebay.co.uk/12V-CHANGEOVER-RE ... 4150a9ef81

EDIT: il probably use the 24v one, as thats what the motor is designed for.