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[03:16:57] <Snert> good as in $2.00 or good as in $25.00 ?
[03:18:53] <Snert> that's where the rubber meets the road I'm afraid.
[07:40:16] <codepython777> Snert: ping
[07:46:40] <theBear> dremel/similar motors these days (maybe always) are basically just bldc like all the bigger drills and cd motors and every effin thing these days
[07:47:45] <Snert> I like little bldc rc heli motors.
[07:48:04] <Snert> the esc looks just like a servo to the arduino.
[07:49:58] <codepython777> Snert: I'm buying motors and finding out that their shafts wobble the discs they rotate
[07:50:04] <theBear> to anything in-fact 1
[07:50:10] <codepython777> Snert: any suggestions on how to fix this?
[07:50:15] <theBear> codepython777, reminds me of when i was a pimp...
[07:50:24] <theBear> codepython777, belts are good
[07:58:46] <codepython777> theBear: where do dremel manufacturers source their motors from?
[07:59:18] <theBear> not seen inside one, but i would assume they custom build/design them into the casing like battery drills and ankle-biters etc
[07:59:40] <Snert> it's just $ but the rc heli motors have good brearings no wobble. No idea how much horsepower you're talking about.
[08:00:43] <codepython777> Snert: I need roughly 300rpm, .5 Nm of torque
[08:00:59] <codepython777> 12v
[08:01:44] <Snert> would a small stepper with a planetary gearhead nema8 do?
[08:02:10] <Snert> I think it exceeds the nM you said.
[08:02:35] <codepython777> Snert: I'm looking for dc brushed to put in a 4 wheel truck
[08:02:51] <codepython777> preferably well made/reliable with low cost if possible
[08:03:51] <theBear> how bigger pilot can fit in this truck ?
[08:04:29] <theBear> 300 rpms isn't a lot, but i suspect too much for any normal stepper vs more bldc style motor
[08:04:58] <theBear> bldc being more like a stepper with only 3 or 6 or 4 or 8 steps maybe
[08:05:34] <Snert> bldc is just more appropriate than stepper
[08:05:39] <theBear> and much lighter, maybe cos you don't need so much coil/magnet if you don't need stop lock/step hard
[08:06:24] <theBear> wait, you mean step-up planetary ? that err, that's gotta be bad for some reason, certainly weird
[08:07:10] <Snert> no, step down planetary but still it's not appropriate
[08:07:20] <theBear> surely those little super-heavyduty "outrigger" inside out rc plane/prop motors are pretty damned balanced and got a decent bearing at least one end ?
[08:08:28] <Snert> they sure do. but it's $. and they're high rpm.
[08:09:08] <theBear> there are a bunch of nice little roughyl pfft, 5 or 8mm toothed belt cogs and belts and bits and pieces around i've seen in everything from robot disco lights with big fat steppers and all manner of stuff attached to them thru to a little 12vdc tool-sharpener tiny-grinder that woulda run probly a couple thousand rpm via such a belt, slightly heavier duty (more cloth/etc in the rubber) quite happily till it didn't
[08:09:46] <theBear> they should go slow happy enough if you "microstep" them (basically drive with nice clean sines rather than on-off-ing)
[08:10:20] <theBear> 3phase, 300hz * 3 coils, that sounds plausible
[08:10:51] <theBear> even if you tradeoff a little magnet/coil for slow speed, tho i spose that's a factor with any relatively un-geared motor
[08:11:07] <Snert> what's the power budget?
[08:11:11] <theBear> (magnet stuff is "better" when it all fast and hard field changes etc
[08:11:17] <Snert> gotta juice it so 6s prolly?
[08:11:20] <theBear> that's the amount of money we got to spend on power <grin>
[08:11:45] <theBear> surely we need to get there quickly ! we do, but don't call me shirley
[08:12:56] <Snert> ali had some kool little maxon swiss motors used.
[08:14:02] <Snert> I like quality so I buy used off ali. couldn't afford anything otherwise.
[08:16:28] <codepython777> Snert: maxon was asking some insane $500 for that spec I gave you
[08:18:52] <codepython777> Snert: What do you buy?
[08:23:35] <Snert> something like this
[08:23:39] <Snert> http://www.aliexpress.com/wholesale?catId=100006833&initiative_id=AS_20160723045604&SearchText=maxon+motor
[08:24:53] <codepython777> Snert: is there a motor manufacturer that is similar to maxon for brushed DC?
[08:25:10] <Snert> no idea actually. prolly so.
[08:25:42] <codepython777> Snert: so you used maxon? how do you control them?
[08:27:05] <Snert> I've been int o getting absolute gray code encoders for cheap. I'll get to the necessary motors later on I suppose.
[08:27:52] <Snert> just happened to see the used maxon motors. I suppose an hbridge would do it.
[08:28:32] <codepython777> Snert: are you using brushed or brushless?
[08:29:51] <Snert> I'm just doing steppers atm. When I get gearing and drive system things figured out more I'll prolly do stepped planetary gear.
[08:30:34] <Snert> maybe a worm drive shoulder type joint.
[08:31:50] <Snert> seen very cool pancake planetary steppers at 100bucks each.
[08:32:16] <Snert> face 2 of those together.
[08:32:26] <Snert> lock the shafts together.
[08:32:36] <Snert> secure the shafts to the frame.
[08:32:45] <Snert> and rotate the motor bodies.
[08:34:26] <Snert> what would it cost with a used ali motor?
[08:34:37] <Snert> 40bucks and an hbridge most likely.
[08:38:25] <Snert> here's 300rpm
[08:38:30] <Snert> http://www.aliexpress.com/item/maxon-DC-motor-Miniature-dc-gear-motor-41-013-013-00-00-200-GP013A024-0067C1A003-12V/32639563130.html?spm=2114.01010208.3.115.wWumDo&ws_ab_test=searchweb201556_0,searchweb201602_4_10057_10056_10055_10037_10049_10033_10059_10032_10058_10017_405_404_407_10040_10060,searchweb201603_8&btsid=1b0d2b61-873c-4a03-bb44-591ed1864573
[12:44:46] <rue_bed> its ok to paste just everything before the ?. we dont need your account information
[12:45:32] <z64555> or do we?
[12:45:38] * z64555 laughs evilly
[12:45:58] * theBear wonders if it was him or that other dude that got googled back there
[12:46:23] <rue_bed> hmm, when is that parade
[12:47:07] <z64555> you can google me anytime. :D
[12:47:44] <theBear> heh, that's what i like to hear
[12:47:57] <rue_bed> 11:00
[12:48:06] <rue_bed> I wonder if I can still make it down
[12:49:23] <theBear> what parade ?
[13:06:33] <Snert> 'twasn't any account info in that.
[13:07:16] <theBear> just 20 or 30 fairly useless g-variables eh ? <slowly shakes head while looking into distance>
[13:08:04] <Snert> 'spose so. But no account information.
[13:08:37] <theBear> as usual i was more worried about not missing the chance for a mini-rant at something that disappoints me in the current world and society that ya know, surrounds us
[23:23:37] <codepython777> anyone here has used cim motors?
[23:31:27] <Buggs> whatup?
[23:31:33] <codepython777> Hi Buggs
[23:31:41] <Buggs> Hey
[23:31:46] <codepython777> just trying to design something around vexpro
[23:32:01] <codepython777> what are you upto?
[23:32:18] <Buggs> Workin on a customer project.
[23:32:40] <Buggs> not sure what vexpro is. ha sorry
[23:32:40] <codepython777> Buggs: which country are you at?
[23:32:49] <Buggs> USA
[23:33:06] <codepython777> what customer project are you working at?
[23:33:29] <Buggs> its a wireless game system. pretty simple stuff.
[23:34:32] <codepython777> cool
[23:34:38] <codepython777> Buggs: what do you do robotics related?
[23:35:58] <Buggs> well, I do more digital electronics stuff.
[23:37:11] <codepython777> cool
[23:37:28] <Buggs> so hows your project going?
[23:37:36] <codepython777> Buggs: just starting
[23:38:14] <codepython777> Buggs: want to build a 4 wheel car (1/8th or so size). Trying to see if i can use vexpro motors
[23:40:16] <Buggs> oh like a scale model?
[23:42:26] <codepython777> yes
[23:42:33] <codepython777> preferably on an H base
[23:45:53] <Buggs> which car?
[23:46:45] <codepython777> I just need a platform so that i can do something with it
[23:46:50] <codepython777> something that can carry some weight around
[23:49:01] <Buggs> sounds cool