Just noticed with your ring shane, looks like the spaces between press lines is pretty consistent at first, then they probably went "arg f*ck this" and they become wider apart.
For friction drives, dewalts would be a bit dodgy... They're shafts are way thin, i wouldn't want to hang any kind of side loads off them.
Did you know you can get long fan motors? I've got one that you might want to try... found it at PnP and its a bit smaller than a mag motor, has a D shaft for mounting and goes hard at 24v.

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Hey angus
Nah, they had to use a different type of press for the in between the lines, when you see the ring you'll see its bent as a perfect circle, its not like heaps of straights with bends. It was pressed, rolled, pressed, rolled. (or something like that).. I was too busy looking at all the metal laying around to really pay a lot of attention. You can see in the pictures theres no straights.

I'd happily try the motors you are suggesting.. Its proving a little worrying at the moment seeing I want speed and torque... and as nick suggested the ring spinner adds friction.

Angus is right about motors with small shafts not taking side loads, but most fan motors are not much better - I can recall the big EV motors broke very easily in the very first version of jolt! Whatever motor you use, I would suggest an extra support bearing. Have a look for a US bot called Tripolar, built be Zac O'donnel (sp?). He built a shell spinner with the same type of drive we are talking about and had heaps of problems at first.
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Australian 2015 Featherweight champion
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outside of the magmotor or brushless i dont think any motor will have the power a 7kg shell needs. a scooter motor 300w type maybe but speed wouldnt be more than 300w before it runs out of power i would think.

if you get a brushless in runner they are tons more tough then the outrunners which are as frail as glass. or a magmotor gearbox
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www.demon50s.com - Minimoto parts
http://www.youtube.com/user/HyzerGlen - Videoooozzz

Just needs one of these

How much weight and space do you have for a weapon motor Shane?
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You and your Torcman fixation An out runner will probably be shaken to pieces, just like Glen mentioned.

A 300W scooter motor would put out less power than a DeWalt I'd think - they are rated for a peak of 1.5HP, plus the scooter are too large diameter and go far too slowly - 2,750 rpm at rated voltage.

I am not advocating the Dewalts as the best thing out there, but they seem the best fit unless you spend stupid amounts of money.
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Australian 2015 Featherweight champion
UK 2016 Gladiator champion

Well, Im happy to build around the ring and motor weights..
I figure the ring will be realistically about 6.5kg (I cant properly weigh it until i get it back) the base aluminium plate is about 2.0kg at least.. its a heavy piece.... but I want to mill parts of it out so that should drop down, but looking at it now, i think its a bit of an overkill...
I figure I'll allow 1.5-3kg for the weapon motor(s), space isnt a big issue as theres plenty of room but the height is.. Ive only got about 75-80mm height to work in..

Ive thought of a horizontal motor layout before... its just finding the right motor... I remember hearing about Jolt and the EV's... And I wouldnt mind going brushless, but the fragile side worries me... I dont mind running 2 or even more providing they can stay within the weight limits...(and i guess power limits)

I dont want something that gets in the match... spins up fast and powerfull and looks all good and stuff then have the batts die after 19 seconds..

got 2 dewalt packs on their way (a123 goodness!!)

lol..

http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=5158

if you think brushed motors are any more robust than something like that you may well think again,

at robowars bender and reboot both broke their motor magnets in bit hits and visceral did it to the original scooter motor, and lets not forget the ever present magmotor magnet issues

i seriously dont think any fan motor would power the shell of that size well enough. phailbot had a 10kg bar powered by one EV warrior style motor and that was thrased after the event and look how much spinning it did.
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www.demon50s.com - Minimoto parts
http://www.youtube.com/user/HyzerGlen - Videoooozzz

Might be worth looking into some smaller Series Wound motorbike starter motors...
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I can't see any motor with a speed under about 10,000 rpm working in this design - did everyone just skip over the maths above? The good thing about the Mag motors is that when their magnets come loose, they can be repaired, but I can't see a Mag working in t his design - its got the torque but not the speed.

A brushless inrunner motor would be interesting if it was well mounted and protected from shock. Just remember what happened to several bots at Robowars; the brushless motors didn't have enough startup torque and their weapons never got spinning. Having the largest possible brushless motor, running it at high speed and using a smaller drive wheel for a large gearing reduction should help make up for the poor low speed torque of sensorless brushless motors.
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Australian 2015 Featherweight champion
UK 2016 Gladiator champion

Thanks Nick,

I think I might start looking at a pair of high speed brushless inrunners.
No other choice I don't think

Start with that hobbycity store - they ae ridiculously cheap! The controller that Glen bought there seems like good value too.
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Australian 2015 Featherweight champion
UK 2016 Gladiator champion

Going to have to wait till payday... I've blown the bot budget for the next 6 months

Still, heres one that sounds the part

"Armature of this motor is made from hardened steel with Kevlar wrapped magnets."

Now that sounds like what I want

That Hobby City site always comes up with a vbscript error on all my PCs, so I can't look at any of their cool toys
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UK 2016 Gladiator champion

I just ran some calculations on the 400 by 85 by 6mm wall ring and it should weigh right on 5kg without any teeth. Adding some modest teeth to bring it up to 6Kg and then spinning it at just 1,500 rpm gives a KE rating of around 2,500 joules, which is quite a it more than Jolt , seems I'm the underdog now!

I had a look at the United Hobbies and the big 77mm by 44m motor with a 700Kv rating would be a good choice with a 10:1 reduction. going much faster than 1,500 rpm will produce so much KE that the bot will risk self-destruction.

Edit:
This just gave me a wicked idea for the Featherweight FBS I was trying to design last year
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Australian 2015 Featherweight champion
UK 2016 Gladiator champion