Richie: The £50, 3 week Featherweight

[tweedermeister]

Tell me about it, my robot was dead in the first fight and got thrown by the flipper twice but survived fine then in the second fight it died part way through got put on the flipper then chucked straight into the arena wall at the end of the fight, it wrecked the hinge for my flipper arm, somehow bent the threaded inserts in the wheels so they are wobbly as they turn rubbing against the chassis and bent the chassis ripping all the fixings out the GR01 motor. I wasn't able to come to the 2nd day as couldn't repair the damage overnight. I think they had turned the power of the flipper right up for the second fight on the Saturday, they probably did the same in the Sunday. Ahh well, part of the game I suppose.

I too fell foul of the floor flipper, hitting the roof. I don't think the floor flippers power was changed though as another bot hit the roof on the Sunday and the flipper seemed to be strong enough to pull that off all event long.

[Revsmin]

If we're on how long a Lipo can last, Flow runs a 4S 3300mAh Lipo with 45C discharge. Lasts five full 3 min fights. Whyachi 550 motors are quite power hungry too.

[Rapidrory]

Yeah the floor flipper was showing no mercy at that event, but at least the crowd enjoyed it! (@ Jarvis: When are the videos going up? I wanna see how Richie landed so I can get an idea of what's probably damaged )

On the batteries; the peak working current I'm ever likely to be drawing is probably around 30A, so one of those cheap 2200mAh 20C should be fine. I'll buy two just in case; at just over £6 each, I think my budget can stretch to that! As for the rest of the upgrades, I think I can manage them all without further spending (aside from maybe a fixings):

I've got some small aluminium box section for the self-righting wings; the rest is just string and elastic bands!

I'm planning to build the front drive belts using some slightly springy, heavy duty string sprayed with belt dressing (The round belts on RS were ~£13 for 5m, and could only take 5Kg of force unless you went to the really expensive stuff). I'm probably gonna have to do a fair bit of experimenting with the drive belts to get something that works reliably, but if they fail in a fight Richie'll still have drive, so it's not too big a problem.

As for spinner proofing, I'm planning to securely attach some ablative bulkheads to the chassis (Aka, bolt on some 2x2 from the firewood pile; gotta keep up the 'rustic' feel :L)

I'm gonna try and keep it looking like a fighting robot rather than just the heavy duty arts and crafts project it seems to be turning into; this is quickly becoming an exercise in 'Redneck' engineering at it's finest

[Rapidrory]

Ok, so minor change of plan; Planning on going to the fight at Guildford, but only have 2 days at home before then in which to repair Richie and make some mods. So I'm going to just upgrade to a LiPo battery, fit new wheels and motor mounts, and fit a self righting mechanism and maybe some extra armour if I have time.

What I was wondering was I've been thinking about getting a set of these wheels http://www.ebay.co.uk/itm/280590873668; I was originally gonna make some from scratch to save money, but due to time constraints and what with these not being very expensive, I thought it might be worth a go. Has anyone had any experience with these/ this type of wheel? Are they actually any good?

[shakesc]

I would suspect that the rubber is quite hard reducing grip levels

[Rapidrory]

Yeah, I considered that.. but if it is too hard I'd either cut some tread in it, or screw some bike tread to it. More concerned as to how solid the center is, and whether or not it would just crack under shock loads..

[plargen]

i got some a while ago and they are a very solid plastic with no grip, bearingboy do good wheels mainly the black and blue are the cheapest and i think the black wheels have the beat grip but i tend to go for the blue as they ware a bit slower

[mrsam]

I was actually considering a set of those exact wheels for Hatchet 2, may have to reconsider now. Having seen the BB wheels on some of the machines at this years champs i can say that they do seem to offer a fair amount of grip and they also seem to be fairly tough, if you don't mind paying the extra i'd go for those.

[Rapidrory]

At ~£2.50 each it's still not a bad price..

Are http://www.bearingboys.co.uk/BZMM80W...e_Wheel-8714-p the high grip black ones you were talking about? According to the data sheets for these wheels(http://www.bilcastors.co.uk/images/c...ls-Cat-Ed4.pdf) the blue ones have the softer tread so should in theory have the better grip and wear the fastest... ?

Bearingboys didn't actually do a small enough version of the blue wheels, but I found an 80mm version sold here: http://www.bilcastors.co.uk/bzmh80wrn-p-1286.html. They're a bit wide, but could be machined down a bit to fit I think...

[shakesc]

Rory, not a bad find
The shore value is a little high. The preferred orange or blue ones from banebots are either 40 or 50 shore

Maybe their nylon wheels and bike tread http://www.bilcastors.co.uk/solid-wh...s-c-54_56.html

[Gaseraki]

I would get those wheels but then screw bike tyre into them.

[Rapidrory]

Well I've got several of those white nylon wheels at home (or at least used to) so that may not be a bad shout... They seem a little brittle from what I remember though; I'd have thought they might crack if you put screws in them...

Now there's the problem that I don't know if I still already have a set of white nylon wheels, and I wouldn't have time to buy them if I get home and not. Plus, though they're only 80p each, they have £5 shipping on them, so I don't want to buy a pair to find I have loads at home... I'll have to give my dad another thing to search for!

[Gabe01]

I have those grey wheels from eBay, with bike tyre screwed into them they grip nicely. I originally used knobbly bike tyre, but hardly got any grip, so I've just changed to motorbike racing slicks, lovely soft rubber.

[mrsam]

@Gabe01 i was worried about the hubs on those wheels not been up to it, do they feel solid enough to you?

[Gabe01]

They're a nice wheel and they feel pretty solid, not battle tested of course. I choose them because they are cheap which means you can have lots of them. When you hold them in your hand they are a nice wheel and certainly not brittle. I used the 'melt-in' method in my drill press and the shafts dropped in easily without compromising the hub strength.