Richie: The £50, 3 week Featherweight

[Ellis]

We used very knobbly tyre for T2's wheels and whilst grip isn't "bad" it isn't massive. I made Rango's wheels with a softer compound fine-pattern knobby bike tyre (local bike/car spares) and the grip the stuff gets with wide wheels is nuts. Harry used the same stuff on Massacre and also found it just stuck to the ground. Perhaps you can find something similar:



It buries a small buttonhead style screw in the pattern nicely.

[Rapidrory]

well I've got loads of old tires and bits of rubber lying around at home... hopefully should be able to find something half decent in there. Though as long as they're better than what I've currently got (which is not hard) for the next event then I'm not too worried; just need to be able to throw it all together in two or three days..

How much does that size of HDPE wheels weigh? Gives me an idea...

[Rapidrory]

Well, once again I had almost no time to do do a ton of work on Richie: this time I had a day and a half to fit new wheels, new motor mounts, a Lipo, and self righting in time for Guildford... I got 3 hours sleep before the event...

The new wheels worked great, all for the cost of £0.00.
All I did was replaced the rubber sheets that made up my wheels with a thick piece of plywood which I lathed round, and then screwed bike tread into. Had no problems with them at Guildford and they had plenty of grip. Also mean I now have about 2cm of ground clearance which is a great improvement, and very much appreciated at Guildford!

The new motor mounts I made worked well too; They were just some blocks of HDPE and wood machined to fit the motor and house a support bearing. I also shifted the motors forward about an inch for better balance. Unfortunately the new wider wheels meant that the back of the motors were less than 1mm away from the linear actuator slider, which meant that when Major Damage decided to hammer me whilst I was on my side, my motors were shifted in and caught on the actuator, which tore out one of the screws holding the motor to the gearbox, leaving me with a very bent drive motor. Marco kindly lent me a hammer to beat it straight again, and I made it through the last two fights fine, but I plan to entirely replace the gearbox housing with metal, and add a rear motor support. They'll basically end up looking a bit like the motors that Gimson sells if all goes to plan.

The Lipo conversion caused an interesting problem; as I no longer had a 2.5Kg SLA in the back of my robot, every time I tried to lift someone I would just tip forward instead. This means I'll have to spend most of my spare weight adding big armour plates or something to the back. I also intend to move my motors to the back when I have time for the 4wd upgrade, which should help a bit.

I fitted a wing type schrimech to Richie before the event, but didn't have time to try and get it working until the break between shows. I quickly found it was much more effective just to have them stuck out permanently, so I plan to replace them with just a bit of stiff plastic pipe. Not pretty, but effective!

Still, all problems aside, I still drove into every fight, and even drove out of a few! Was a lot of fun, and am planning to do a lot of upgrades when I get more than a day or two to work on it!

Oh and on a side note, if anyone here does antweights and is looking for an ESC, I've finally started taking orders on my home made antweight speed controllers. See http://robotwars101.org/forum/viewto...=2128&start=75 for more details.

[daveimi]

I am interested in an ESC off you Should I PM you etc?

[Rapidrory]

Check the second to last post in the thread (http://robotwars101.org/forum/viewto...=2128&start=75) for details on ordering.

[Rapidrory]

In an unprecedented turn of events, I'm almost ready for an event more than a few hours in advance!

The chassis has been completely rebuilt to make it 2 inches wider and 1 inch longer... sounds like a lot of effort for very little, but the extra width stops the motors catching in the lifter, and the extra length gives it some more stability lifting

WP_20140730_010(3).jpg
(Richie During rebuild)

The motors have also been rebuilt with new aluminium plates between the motors and gearboxes; should stop them bending in half so easily:

WP_20140709_009.jpg

The motor mounts are the same, but they're mounting onto a much stronger frame. The motor mount for the lifter has also been improved.

WP_20140730_010(4).jpg

New ESCs have been fitted for all motors due to my homemade one randomly dying during testing... The drive ESCs are not homemade, but they're really cheap chinese ones that I've heavily modified to actually work. Feel slightly bad for using bought ESCs, but they don't lock up with sudden stick movements at least.

The armour's the same old, just stretched out a little to fit the bigger chassis.

Just need to tidy up the electronics, refit the armour, and maybe add some weights at the back and I'm pretty much done
Here's a vid of some rather mediocre testing: https://www.youtube.com/watch?v=h06Z...wp0tSCHzqPS4jQ

[shakesc]

Looking good
I'm almost ready, usually more prepared than this!

[shakesc]

New ESCs have been fitted for all motors due to my homemade one randomly dying during testing... The drive ESCs are not homemade, but they're really cheap chinese ones that I've heavily modified to actually work.

-- So what sort of mods?

[Rapidrory]

Bigger cables, noise suppression, new firmware etc...
I go into detail on it in this thread: http://www.fightingrobots.co.uk/thre...heap-drive-esc

[RogueTwoRobots]

Nice test video. The robot looks great and definitely got that old-school feel to it, almost makes me want to go out and pick up a pair of wiper motors

[Rapidrory]

Damn it house robots!

WP_20140914_005.jpg

[Niels - Team K.a.L.M.]

That is one video to watch out for

what happened?

[Rapidrory]

Featherweight house robot (Battle Axe?) hammered it after it blew it's fuse... some how tore the armour up pretty bad. Also hit the roof at some point courtesy of the floor flipper... Mechanically it's all still fine at least, which is the important part :L

[Rapidrory]

Looking at upgrading the lifter motor to something with a little more poke but without spending any real amounts of money.

Came across a pair of Johnson 600's on eBay (here) for £8.50 (or 3 for £10). Looking at the spec sheet with them, they seem quite a lot better than the 550 I'm currently running.

$_57.JPG

Does anyone know anything about these motors; are they actually any good? If so, I'm considering buying the 3 for £10 and upgrading my drive as well (though slightly cautious about trashing the drill gearboxes...)

[Revsmin]

I'd assume they are considering the Johnson 885s Ellis got for Rango were total powerhouses for near enough £5, and they only blew because the gear ratio was wrong (through no fault of his I might add). I'd say try them and see, especially for that price!