new Roboteer asking for building tips and so on(First robot)

Just to let you know I grew up with robot wars coming home from school turning the T.V to BBC2 back then I was inspired to build a combat robot back then but i was just a child and didn't know how to build one but after finding this forum and having a good read I'm inspired again.

So to get to the point I'm building an invertible Rambot called Rukia. I want to build Rukia to be strong enough against Spinners and i have made a mistake on speed controller's I have a Sabertooth 25A Dual and the Motor's are speed 900 so yeah not going to work. I believe i need 2X Victor 883.

chassis - steel i think it's strong enough.

armor - i'm thinking of polycarbonate, kevlar, hardox or something else.

weapon - speed and strength and ramming shield if i have some Weight.

power - 18v or 24v NiCad or NiMh don't know yet

and yes i'm building my on gearbox.

Hiya Lewis, and welcome to the forum :)

As the owner of a fully steel (and a little hardox) rambot, and having run speed 900's for a while now, I would highly recommend the victor 883's, the fans are sometimes suspect but generally speaking they are great speedos, they can dump as much current as you need into speed 900's in an instant. You will need a special mixer for the victors which is sold on the Robot Market Place website, because IFI speedos need a boosted signal to work, and the mixer does that.

dave im gonna be using 2 speed 900s with victors, but i didnt no about the mixer , u got a link for it? cheers

you can easily sell the sabretooth through the for sale section. I'm pretty sure that with an influx of new builders recently, there will be many people happy to take it off your hands

I like to here what mixer you recommend for the victors and is hardox easy to work with?

Apparently you can now use either an single signal booster:
http://www.robotcombat.com/products/IFIW-SIG36.html

Or the mixer:
http://www.robotmarketplace.com/products/RL-IMX1.html

Less cabling for the mixer, but your call.

And hardox is a bit of a b!tch to work with, you can cut it with a good angle grinder, though you may wear out a few discs, and its very resistant to drilling, you really need cobalt drill bits or better and a lot of coolant.

hardox isn't too bad to work with if you get yourself a 230mm angle grinder and take it nice and easy. I've only burned through discs when I've tried to force my way through it. As dave mentioned, you'll need some cobalt drills to drill through it, plenty of coolant and be prepared to resharpen them every dozen holes or so

Don't need to bother ordering a signal booster. Make one yourself

viewtopic.php?f=111&t=3280&p=101274&hilit=victor#p 101274

I like to ask more about Hardox. I know it's a type of Steel but what's the difference of Hardox to Steel and Stainless Steel.

Short answer: it's stronger :) Hardox is the brand name for a type of wearplate steel, it's extremely strong and hard stuff but marginally denser than 'normal' steel (roughly the same density as stainless) and - mounted correctly - is the armour of choice for withstanding most large spinning objects.

I have been thinking, how i my going to give power to the Receiver? does Receiver get power from the battery or does it get power from the victors?

The victors do not have a BEC (battery eliminator circuit). You will therefore having two options, use a receiver battery pack

http://www.technobotsonline.com/ni-mh-4 ... 00mah.html

or use a seperate BEC

http://www.technobotsonline.com/smartbec-5v-1.25a.html

I seen Hardox that have numbers 300 to 600 is it like grades for titanium?

I belive that number is the Brinell hardness.

Ok so the numbers are the Brinell hardness so let's say i get hardox 600 can i still use a 230mm angle grinder and cobalt drills and does the weight change?

yes, yes (it will be more of a bugger to drill and cut) and no.

You may struggle to find thin enough hardox 600. Can't remember what the min thickness is but i remember it being thicker than the 4mm hardox 400

In a featherweight if you angle your armour 4mm Hardox 400 will be more than enough.

Yes I agree 4mm hardox is plenty in a featherweight. Many of the parts you need to build a new machine can also be found on our website www.robochallenge.co.uk

I like to ask about wheels and drive shafts, first i know that wheels have a plain or a nut. But what i like to ask is how do you attach wheels that have no plain or a nut? and how you attach the shaft to the chassis.

ok I'm not explaining this very well, basically what I'm asking for is the number of ways to assemble the drive.

way i prefere to do it, have a fixed shaft, which can just be a bolt which is just fixed to a bulk head or something, and get a robochallenge wheel with bearings in the actual wheel hub then it just spins freely on the bolt and a pully or sprocket can be bolted to the wheel to give it drive

or have it, so bearings are mounted in a bulk head which would then allow the axle to spin instead of it being fixed with wheels etc being secured to the shaft

Ok so how do you fit the bearing in the wheel hub? and while I'm at it how thick does the steel bar's for the chassis you recommend 16x16mm or something like 20X20mm.

Either pop the wheel on a lathe and bore it out to the desired dimension and press the bearing in or pop it under a pillar drill and drill it slightly undersized, heat the bearing and press it in. The heat will cause the plastic to melt out the way.

Size wise for a featherweight axle 10mm diameter will do happily. Bearing in mind that drill gearbox shafts are around the 8mm mark.

I'm having trouble finding a 12v LED and I'm looking for a suitable axles, for my bosch 35w motors.

just buy a regular led and put a resistor on it :)

http://www.technobotsonline.com/opto-el ... ators.html

A range of 12V and 24V LEDs in red, green and yellow.

Axles for the Bosch 35s may have to be a custom job.

i think although not 100% sure but

something like a 4mm allan key will fit nicely into those motors

not sure its 4mm though worth a try as its cheap

I use 4mm keyway steel, fits perfectly. Available from any engineering shop, probably on ebay and RS.

See here for one way of doing it http://www.teamstorm.com/feathers/forcex.htm (at the bottom)