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[02:55:18] <rue_shop3> my cnc pendant is working, now I just have to finsih boxing it up
[09:35:44] <pokmo> hi
[09:36:22] <pokmo> does anyone know of a cheap but decent 3-axis gyro?
[09:36:31] <pokmo> i'm already using the L3GD20 but would like to try something else
[09:37:27] <deshipu> I use a GY-61
[09:37:32] <deshipu> it's really cheap...
[09:38:33] <pokmo> deshipu, is it a ADXL355 onboard?
[09:38:55] <pokmo> ADXL335 rather
[09:39:16] <SpeedEvil> pokmo: why? the L3 is $3
[09:39:52] <pokmo> SpeedEvil, just wondering if there're newer ones out there around that price range
[09:40:23] <SpeedEvil> What features are youwanting. Look at digikey for the random walk spec, for example
[09:41:01] <deshipu> pokmo: yeah
[09:41:20] <deshipu> pokmo: it's quite crappy
[09:42:14] <pokmo> deshipu, yeah i've tried. i wonder if the chips were fake. ADXL335 is rather expensive
[09:42:41] <pokmo> SpeedEvil, ok i'll check digikey
[09:45:17] <SpeedEvil> Analog accels are in general more expensive
[09:45:52] <deshipu> one would think they need less silicon
[09:47:22] <SpeedEvil> Doesn't work that weay.
[09:47:44] <SpeedEvil> The inside analog nodes need almost exactly zero drive,and no static protection
[09:48:04] <SpeedEvil> Plus, mass production.
[09:56:07] <SpeedEvil> Oooh - interesting - cheapish accels at $4 each are coming down sometimes from the standard 150ug/sqrt(hz)
[09:56:17] <SpeedEvil> http://www.st.com/content/st_com/en/products/mems-and-sensors/accelerometers/lis344alh.html is at 50
[10:08:37] <pokmo> the MPU6050 breakout go for like $3 each but the digikey is selling the chip for $3.5 @5k. are those on the breakout fakes?
[10:08:48] <pokmo> or rejects
[10:09:14] <pokmo> in fact, the breakout go for $1.25 each
[10:09:27] <pokmo> so the chip alone is selling for twice as much
[10:09:27] <SpeedEvil> There are clone sensor chips
[10:09:41] <SpeedEvil> I don't happen to know if those ones are fake
[10:09:54] <pokmo> SpeedEvil, clone - are they counterfeits?
[10:10:11] <pokmo> how do they have the knowhow to clone a chip?
[10:10:13] <SpeedEvil> There are some out tehre, yes.
[10:10:19] <SpeedEvil> there are many ways toclone a chip
[10:10:45] <SpeedEvil> you can have ones with more-or-less similar features. Or one that's designed to work in the same circuit, and probably without software changes.
[10:10:59] <pokmo> right
[10:11:09] <pokmo> but could digikey be inflating the prices?
[10:11:16] <SpeedEvil> Or one that pretends tobe the original chip and is sold as it. And then you have mask level cloning - where they try to reverse engineer and simply copy the chip
[10:11:29] <SpeedEvil> Digikeys prices are higher for various reasons - some of them good.
[10:12:01] <SpeedEvil> They don't for example ever sell defective parts that were destined for the bin as new.
[10:12:17] <SpeedEvil> Maintaining a clean supply chain is unfortunately expensive.
[10:12:43] <pokmo> and these breakout boards could well contain defect chips?
[10:13:41] <SpeedEvil> You have little control on if they do or don't.
[10:13:48] <SpeedEvil> If you can test each one, you're probably OK.
[10:14:17] <SpeedEvil> But if you're puttingthem into a product, you absolutely can't risk faulty parts getting to consumers.
[10:24:22] <pokmo> sure
[13:21:19] <justan0theruser> where can I find a self-adjusting tensioner for AT10 belt
[13:28:49] <deshipu> have you looked under the bed?
[13:30:20] <justan0theruser> no
[15:21:09] <justan0theruser> where can I find an automatic tensioner
[15:22:12] <robopal> what is that?
[15:22:45] <justan0theruser> a tensioner with a spring attached, maintains a constant tension in a pulley belt
[15:24:49] <justan0theruser> lol
[15:32:12] <z64555> justan0theruser: you make one
[15:32:52] <justan0theruser> I'm looking on ebay
[15:33:16] <z64555> All the tensioner is, is just a pulley that can slide around in a track, or pivots from an arm
[15:33:19] <justan0theruser> I guess I could make one, but not really desiring to...
[15:33:34] <justan0theruser> "in a track"?
[15:33:38] <z64555> and then you have a spring
[15:33:55] <z64555> It's a hole
[15:34:43] <z64555> It's a hole that has the diameter of the axle of the pulley, and some length
[15:34:59] <justan0theruser> whats a hole
[15:35:00] <z64555> If the length is the same size as the diameter, then it's just a circular hole
[15:35:11] <justan0theruser> wut
[15:36:19] <z64555> how do you not know what a hole is? You use a drill to make them!
[15:36:34] <z64555> but for the track, you'd use an end mill or a router
[15:36:52] <justan0theruser> "It's a hole"
[15:36:55] <justan0theruser> whats a hole
[15:37:29] <justan0theruser> what is it
[15:37:33] <justan0theruser> no pronouns please
[15:37:44] <z64555> hole. noun. Also known as a cavity or void
[15:38:01] <justan0theruser> what is it
[15:38:09] <justan0theruser> what is "it"
[15:38:24] <z64555> the hell are you going on about?
[15:38:33] <justan0theruser> I'm asking you what you're talking about
[15:38:46] <justan0theruser> you just out of no where used the pronoun "it" and I have no idea what "it" is
[15:38:49] <z64555> I did, but for some reason you're not understanding a word I'm saying
[15:39:08] <justan0theruser> No, I just asked you to clarify what your pronoun was referring to
[15:39:37] <justan0theruser> or were you just informing me of the tautology, "a hole is a hole"?
[15:40:04] <z64555> "in a track"? "It's a hole that has the diameter of the axle of the pulley, and some length" "whats a hole" "hole. noun. Also known as a cavity or void"
[15:40:28] <justan0theruser> the track is a hole?
[15:40:32] <z64555> yes!
[15:40:50] <justan0theruser> that is what I was asking
[15:41:14] <justan0theruser> I think I want to use an arm
[15:41:14] <z64555> you got horribly out of sequence, and ended up confusing me :P
[15:41:40] <justan0theruser> I wonder how hard this would be to monut
http://www.ebay.com/itm/Gates-38106-Belt-Tensioner-Assembly/272404663959?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D2%26asc%3D38530%26meid%3Da951b901b9d546e98613d4866b7cec5c%26pid%3D100005%26rk%3D1%26rkt%3D4%26sd%3D272237049324
[15:43:14] <justan0theruser> I'm not even sure how it's mounted, I guess it's just a press fit?
[15:44:35] <z64555> That's the second version I mentioned. It's mounted on a lever, and the bushing around the lever's axis is actually a spring
[15:44:42] <justan0theruser> right
[15:45:00] <justan0theruser> does that look like a press-fit to you?
[15:45:41] <z64555> so you'd install it to a stationary plate using a bolt and washers, and crank down on the bolt
[15:46:07] <justan0theruser> stationary plate?
[15:46:17] <z64555> yeah.
[15:46:25] <z64555> oh. wait, it has a little pin on the back
[15:46:48] <justan0theruser> ?
[15:46:49] <z64555> So you'd drill two holes, one for the mounting bolt, and the other hole for that pin
[15:47:02] <z64555> http://i.ebayimg.com/images/g/a7AAAOSwhglTwgO8/s-l300.jpg
[15:47:21] <justan0theruser> I see three holes?
[15:47:24] <z64555> Left side, there's a cylinder sticking out from the plate
[15:47:31] <justan0theruser> ohh
[15:47:36] <justan0theruser> good catch
[15:47:51] <justan0theruser> I guess I can buy it and measure it...
[15:48:23] <justan0theruser> why can't I find the tension of the spring in it?
[15:48:32] <justan0theruser> doesn't that seem like something they should tell me?
[15:48:39] <justan0theruser> (looking at
http://www.oreillyauto.com/site/c/detail/GATE/38106.oap?year=1990&make=Chevrolet&model=Astro&vi=1027965&ck=Search_03309_1027965_-1&pt=03309&ppt=C0331)
[15:50:27] <z64555> Because its a product replacement part
[15:50:50] <justan0theruser> right... but it tells you the diameter and width
[15:52:24] <justan0theruser> hmm
[15:52:39] <z64555> presumably because you can swap out the spring. I guess look around and see if you can find an official data sheet on it
[15:53:42] <justan0theruser> are rounded springs for this purpose common?
[15:54:40] <z64555> not sure what you mean by "rounded"
[15:54:59] <z64555> Given its configuration, it's most likely a helical spring in there
[15:55:40] <justan0theruser> I mean a spring that is helical and that helix is in a circle
[15:55:43] <justan0theruser> or semicircle
[15:56:18] <z64555> no, I don't believe so
[15:57:01] <justan0theruser> do you think that the tension is very high given that this is meant for a car?
[15:57:56] <z64555> I'd imagine its on the order of 10 to 20 foot pounds
[15:59:22] <justan0theruser> this one looks even easier to mount
http://www.ebay.com/itm/Belt-Tensioner-Assembly-DriveAlign-Premium-OE-Automatic-Belt-Tensioner-GATES-/400939685634?hash=item5d59de1702:g:hWMAAOSwu4BVlnOY&vxp=mtr
[16:00:11] <justan0theruser> I'll just email drivealign
[16:00:50] <justan0theruser> or gates I mean..
[16:02:39] <justan0theruser> Z64555: so this might be a dumb question, but that is not related to the torque a motor is rated for right?
[16:03:04] <justan0theruser> I won't stress the motor if it applies more torque than my motor is rated for?
[16:03:49] <justan0theruser> because due to the tensioner, both sides of the belt will be pulling the motor shaft when the motor is at rest, so the motor shouldn't be doing any work?
[16:05:14] <justan0theruser> I might buy this and just expirement with it, :P
http://www.ebay.com/itm/Dorman-419-109-fits-GM-V8-Automatic-A-C-Belt-Tensioner/141740214681?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D2%26asc%3D38530%26meid%3D3f8a827634ce4e35af718ceda78ce07f%26pid%3D100005%26rk%3D5%26rkt%3D6%26sd%3D400939685634
[16:08:12] <z64555> The tension of a belt is a factor in all of the pulleys' frictional torque
[16:08:44] <justan0theruser> right
[16:08:50] <justan0theruser> but it isn't 1:1 is it?
[16:08:53] <z64555> no
[16:08:53] <justan0theruser> it's 1:mu?
[16:09:32] <z64555> the frictional torque is a function of the belt tension and contact area per pulley
[16:10:05] <justan0theruser> is it generally minimal?
[16:10:07] <justan0theruser> Less than 5%?
[16:10:23] <z64555> I have no idea what the numbers would actually be
[16:10:29] <justan0theruser> ok thanks so much for the info
[16:10:44] <z64555> yw
[21:12:43] <rue_shop3> ok, cnc pendant is finished, and the step interceptor, I just need to install it now
[21:38:12] <Tom_L> rue_shop3, making good progress i see
[22:16:09] <rue_shop3> yea!
[22:29:35] <rue_shop3> armyofevilrobots, ah, I have another thing
[22:29:48] <armyofevilrobots> shoot.
[22:29:58] <rue_shop3> its a air puff controller, it outputs a 200ms pulse every 10 seconds to clear chips
[22:35:11] <rue_shop3> :)
[22:35:19] <rue_shop3> sometimes its the simple things
[22:35:53] <rue_shop3> I'm really surprised at how slow you have to cut plexiglass/cd case
[23:00:50] <Tom_L> i didn't run mine very quick
[23:00:59] <Tom_L> but it was a small bit
[23:01:55] <rue_shop3> yea, 10 seconds between puffs seems to be fine
