#emc-devel | Logs for 2007-12-21

[01:18:46] <cradek> some time ago I coerced my irc client into highlighting messages containing "chris" as being for me. this time of year that doesn't work very well.
[01:21:36] <skunkworks> heh
[01:22:27] <skunkworks> how does the gecko smell?
[01:29:37] <skunkworks> can you have it highlight for messages containing "chris "?
[01:30:20] <skunkworks> I suppose that doesn't take into account punctuation
[01:35:15] <SWPadnos> chris and not {saint,nick,[ck]ringle,claus}
[01:35:28] <SWPadnos> but that would miss things like "that chris, he's such a saint"
[01:39:58] <skunkworks> :)
[01:40:08] <skunkworks> atleast he gets those now..
[01:41:21] <skunkworks> I went to see my neice get christened
[01:42:10] <skunkworks> niece
[01:43:19] <SWPadnos> had it right the first time :)
[01:43:31] <SWPadnos> or the second. what the hell is wrong with me
[01:43:38] <skunkworks> heh
[01:43:44] <skunkworks> I googled it actually..
[01:44:07] <skunkworks> The I before E rule works for that one :)
[01:44:10] <SWPadnos> heh
[01:46:13] <cradek> http://timeguy.com/cradek-files/emc/chris.png
[01:46:30] <SWPadnos> oh christ
[01:50:59] <skunkworks> I was trying to think of other words that contain chris to be even more annoying than I already am.. but I lost interest.
[01:56:27] <jmkasunich> thats ludichris
[01:56:52] <jmkasunich> redichris even
[01:59:31] <SWPadnos> skreek engcrish
[01:59:40] <SWPadnos> err - engchrish
[02:54:48] <cradek> http://timeguy.com/cradek-files/emc/CLIP0096.ASF
[02:58:03] <SWPadnos> looks like there's a permissions problem on that file
[02:58:29] <cradek> fixed - I always get that wrong
[02:58:33] <SWPadnos> heh
[03:00:17] <jmkasunich> ok, how many people can hit chris's DSL at once?
[03:00:26] <SWPadnos> of course, I probably can't play it
[03:00:35] <SWPadnos> well, I take it that's at least two :)
[03:00:41] <cradek> I didn't reencode this one. it may be better or worse for you
[03:00:48] <SWPadnos> I suspect it will be
[03:00:58] <cradek> ha
[03:01:01] <SWPadnos> it's going to try to play in Winamp this time, instead of real
[03:01:33] <SWPadnos> sigh. I wish my Dapper computer would have correct permissions on the CD recorder
[03:02:52] <SWPadnos> wow - it played
[03:02:55] <fenn> * fenn waits for skunkworks to put it on youtube
[03:02:59] <SWPadnos> was that just jogging?
[03:03:09] <cradek> no, it's g0 stuff
[03:03:18] <SWPadnos> ok, single axis moves?
[03:03:19] <jmkasunich> it whines a lot
[03:03:20] <cradek> jogging (teleop) doesn't work very well right now
[03:03:34] <cradek> one of the moves is something like g0b45c45
[03:03:43] <cradek> and then back
[03:03:50] <SWPadnos> ok, was the XY motion compensation or programmed?
[03:03:59] <cradek> there was no XY motion
[03:04:07] <SWPadnos> well, I saw the table move :)
[03:04:10] <cradek> the table moved around to compensate for the rotary joint pivots
[03:04:18] <SWPadnos> ok, that was the answer
[03:04:20] <jmkasunich> there was saddle and table motion, not X and Y
[03:04:23] <cradek> XY is the workpiece (penny) and the tooltip did not move
[03:04:39] <SWPadnos> I'm not sure that's "correct" behavior then
[03:04:39] <cradek> i.e. it works right
[03:04:46] <cradek> yes I'm pretty sure it is
[03:04:55] <SWPadnos> if I program C360, I may be doing it to mill a circle in something
[03:04:59] <cradek> it's what I meant anyway
[03:05:07] <SWPadnos> I know it's working as designed :)
[03:05:23] <jmkasunich> c changes the orientation of the tooltip
[03:05:27] <cradek> if you want to make a circle on the workpiece, you better program G2 or G3
[03:05:30] <jmkasunich> you wanna mill a circle, use G3
[03:05:49] <cradek> if you want to move the tooltip orientation around at the same time, you'd have a C word in your G3
[03:05:59] <jmkasunich> I assume the gecko is running C?
[03:06:01] <SWPadnos> if I want to make a groove in the outer edge of a disc, I may want to position the head (tilt), and then spin the C table
[03:06:02] <cradek> yes
[03:06:30] <cradek> SWPadnos: your machine could work differently from mine, but I think yours would be the unusual one
[03:06:36] <SWPadnos> could be :)
[03:06:48] <SWPadnos> that's why I'm not sure if it's "correct" behavior
[03:06:49] <jmkasunich> cradek: his last statement does seem to show a problem
[03:07:00] <cradek> which?
[03:07:16] <SWPadnos> rotaries are used for essentially engraving on the edge of cylindrical objects
[03:07:21] <jmkasunich> if you want to mill a v-groove around the OD of a part
[03:07:33] <jmkasunich> tilt B to 45 to make a V with the corner of the endmill
[03:07:35] <cradek> these aren't rotaries. They're tool direction orientators
[03:07:57] <SWPadnos> hmmm
[03:08:00] <cradek> jmkasunich: you would program g0x1y0c0; g0b45; g3x1y0i-1j0c360
[03:08:08] <cradek> or that with the bugs removed
[03:08:38] <jmkasunich> IOW, you tell it "cut a G3 circle while rotating the tool as you go"
[03:08:42] <cradek> it will end up that all motion cancels except the C joint
[03:08:46] <jmkasunich> and the kins rotates the work instead
[03:08:46] <cradek> exactly
[03:08:52] <SWPadnos> hmmm
[03:09:02] <SWPadnos> that seems counterintuitive to me
[03:09:07] <cradek> you program the tool's path and orientation along the workpiece
[03:09:18] <SWPadnos> but I'm sure there are things that would be counterintuitive if it were done "my way" also
[03:09:19] <cradek> you don't have to worry about the machine's configuration
[03:09:28] <cradek> SWPadnos: yeah like the motion you see in that video.
[03:09:32] <SWPadnos> heh
[03:09:35] <jmkasunich> SWPadnos: it is a bit, but the advantage is that the same g-code would yeild the same result even if the machine had both rotaries on the head, or both rotaries on the table
[03:09:36] <cradek> it would be impossible actually
[03:10:09] <jmkasunich> cradek: I got a neat test for you
[03:10:21] <cradek> I'm going to try the thing I recently said
[03:10:23] <jmkasunich> spiral mill a hole, then tilt the head and chamfer the hole
[03:10:32] <jmkasunich> (using the side of the mill)
[03:10:39] <cradek> I have to make some clamps before I actually cut anything
[03:10:47] <jmkasunich> and do it with the hole _not_ centered on the rotary
[03:10:58] <jmkasunich> (swampy's way couldn't deal with offcenter stuff)
[03:11:01] <cradek> that'll just work :-)
[03:11:17] <cradek> but I need joint limits!
[03:12:21] <SWPadnos> ah yes - the deburring tool motion would be hard my way
[03:12:59] <jmkasunich> oh, really twisted - do the spiral mill and debur thing, but make the hole at an angle!
[03:13:23] <jmkasunich> that would require G2 or 3 in uv I think, is that possible yet?
[03:13:43] <cradek> not quite yet
[03:13:58] <cradek> I didn't show it in my video, but I have UVW correct in these kins too
[03:14:25] <cradek> interesting U is just the saddle joint
[03:14:45] <cradek> V varies by B's angle but is always the table and Z joint
[03:14:58] <cradek> much easier than stuart's machine
[03:15:24] <jmkasunich> what is the configuration of stuarts machine? both angular axes on the head?
[03:15:28] <cradek> yes
[03:15:34] <cradek> it's like the simulator
[03:17:07] <jmkasunich> have you seen that machine in person?
[03:17:18] <cradek> yes
[03:17:37] <jmkasunich> does the motor tilt and swivel with the spindle, or does it use a gear train of some kind?
[03:17:38] <cradek> the original control is still on it
[03:18:01] <cradek> I think the motor moves
[03:18:20] <jmkasunich> ok
[03:18:30] <jmkasunich> (gathering datapoints for next project)
[03:20:54] <jmkasunich> I really have to figure out what I want for a spindle
[03:21:04] <cradek> btw, the strategy I gave does move just the horizontal rotary, so you can mill the groove swp wants
[03:21:13] <cradek> it took me a few tries to get it right of course
[03:22:07] <SWPadnos> ok. I don't feel so bad if it wasn't trivial
[03:22:20] <cradek> well who can program the right arc on the first try?
[03:22:37] <cradek> (I only had to program C-180 instead of C180 which is what I tried first)
[03:22:53] <cradek> if I thought about it for a while, maybe that reason would be obvious, or maybe C rotates the wrong way
[03:23:09] <cradek> or, I should have used the other of G2,G3
[03:23:34] <SWPadnos> hmm. Stuart had mentioned something with his kins file where the offsets needed to be negative
[03:23:47] <SWPadnos> dunno if that's related
[03:23:51] <cradek> he figured that out
[03:23:58] <SWPadnos> oh, good
[03:24:06] <cradek> he copy/pasted some of my code :-)
[03:24:38] <SWPadnos> well, that's one way to do it :)
[03:24:49] <cradek> no, that was why it was strange
[03:25:02] <cradek> I'm impressed by what he has figured out.
[03:25:05] <SWPadnos> yeah
[03:25:09] <SWPadnos> no kidding!
[03:27:24] <cradek> I sure am going to need home switches. it's a huge pain without them
[03:29:25] <cradek> [449277.581557] RTAPI: ERROR: Unexpected realtime delay on task 1
[03:29:32] <cradek> ouch, the usb camera
[03:30:04] <SWPadnos> heh
[03:30:14] <SWPadnos> looks like mass storage
[03:30:20] <jmkasunich> if it hurts don't do it
[03:31:19] <cradek> yep
[03:34:05] <cradek> hmm, there's a cradek youtube account. I wonder if it's me.
[03:35:34] <cradek> (I used to be so good at the internet...)
[03:36:06] <jmkasunich> you haven't changed, the internet has
[03:36:50] <cradek> that's so true
[03:37:17] <cradek> other than "it's not available" I can't figure out anything about the cradek account
[03:37:35] <cradek> I told it cradek forgot his password, and I didn't get the email. I guess that's a good sign it's not me
[03:44:14] <jmkasunich> somewhere around here I have a small plastic bag with m3 (or maybe its m2.5) screws in it
[03:45:42] <jmkasunich> last time I used them was about a year ago - I think its a lost cause
[03:46:04] <SWPadnos> box#5, shelf 2
[03:46:06] <cradek> * cradek hands jmkasunich a 4-40 tap
[03:46:24] <jmkasunich> I dunno if there is enough metal
[03:46:42] <jmkasunich> these are the screws that let you bridge multiple DIN rail type terminal blocks together
[03:47:40] <SWPadnos> oh - depends on the blocks too then
[03:48:04] <jmkasunich> the bar inside the terminal block is 0.175 wide, with the screw hole in the middle
[03:48:08] <SWPadnos> I have a sack of them too (but I know where they are, more or less :) )
[03:48:25] <jmkasunich> drilling it out big enough to retap might not leave much
[03:49:24] <fenn> hey you could make them on your CNC lathe!
[03:50:13] <jmkasunich> don't have a spindle encoder yet
[03:51:10] <fenn> i'm wondering how hard it would be to make a hex wobble broach
[03:51:31] <jmkasunich> didn't find the screws I know I have somewhere, but I found some other screws that will work
[03:57:44] <cradek> http://www.youtube.com/watch?v=7WCrqqoZkPg
[04:06:15] <jmkasunich> anybody see where I put down my centerpunch?
[04:07:03] <cradek> by the M2 screws
[04:07:58] <fenn> under a piece of paper
[04:08:08] <cradek> to your right (seriously)
[04:08:32] <jmkasunich> on the 1" wide sliver of countertop at the headstock end of the machine
[04:10:07] <fenn> you could get rid of that
[04:12:19] <jmkasunich> then I'd just find some other out of the way place to leave things
[04:26:24] <cradek> whee, I put my 30-60-90 triangle on the table and went to B30. Now the V axis cuts right along it. This is extremely useful.
[05:00:14] <jmkasunich> for engraving things on each face of those platonic solids
[12:54:10] <cradek_> cradek_ is now known as cradek
[13:33:35] <skunkworks_> cradek: very cool video.
[13:33:43] <skunkworks_> have you machined anything yet? :)
[13:34:11] <skunkworks_> your descriptions are a lot more informative than mine :)
[13:34:23] <alex_joni> heh
[13:34:35] <cradek> only air. I have other things to do first (make clamps for C, maybe make a tool length measuring fixture of some kind
[13:34:39] <cradek> )
[13:34:57] <skunkworks_> how do you like the gecko?
[13:35:14] <cradek> it's easy to use and seems to be strong at the motor
[13:35:29] <alex_joni> any difference in sound?
[13:35:58] <cradek> definitely smoother at low speed but that's the major difference I've noticed so far
[13:36:13] <cradek> I might hook it up to a linear axis and see if it goes much faster.
[13:36:32] <alex_joni> I don't think it will be much faster
[13:36:36] <alex_joni> maybe better accels
[13:36:55] <cradek> accel is already very fast
[13:40:57] <cradek> bbl...
[14:58:27] <jepler> cradek: is it accurate to say that a 5-axis gcode file would "mean the same thing" for both the simulated machine with BC stacked on the spindle, and for your machine with C on the table and B on the spindle?
[14:59:07] <cradek> yes I think so.
[14:59:47] <cradek> other 5-axis machines are AC and AB though. It seems like the gcode would be different (not just in the obvious way of the letters being different)
[15:02:10] <jepler> it seems like using any pair of rotaries lets you specify any tool orientation you like. I would like to understand if there's some use to actually having all three rotaries..
[15:03:25] <cradek> I don't think so. with a spinning tool there's one DOF you don't care about.
[15:04:18] <jepler> (so you can have 6 orders: AB AC BC BA CA CB; either you can have them both move the work, both move the spindle, or the first move the work and the second the spindle. That gives 6*3 = 18 distinct geometries, each with some associated constants related to physical distances on the machine)
[15:06:43] <cradek> good thing I don't care if there's a general 5axis kins
[15:08:54] <jepler> is the kinematics module for max in CVS?
[15:10:20] <cradek> http://cvs.linuxcnc.org/cgi-bin/cvsweb.cgi/emc2/src/emc/kinematics/Attic/maxkins.c?rev=;hideattic=0;only_with_tag=w_tool_length
[15:12:24] <alex_joni> cradek: are you sure you don't care about one DOF ?
[15:13:13] <alex_joni> I am pretty sure you need 3 DOF's to position a point in space, and 3 additional DOF's to orient a vector at any angle starting from that point
[15:13:57] <cradek> nope, you need only 5.
[15:14:04] <alex_joni> err.. I think I see the issue (you're assuming the 6th DOF collinear with the spindle axis)
[15:15:03] <cradek> well in the general case if you want a vector from a point (xyz) pointing in a certain direction (theta, phi in spherical coordinates) that's only 5
[15:16:08] <alex_joni> but if you want to spec. it in carthesian space you need XYZABC.. right
[15:16:17] <cradek> if you specify the vector direction in rectangular coordinates it takes 3, but it's overspecified (length of vector is the wasted DOF)
[15:18:00] <cradek> well the rotaries ABC are exactly like spherical coordinates. 3 of them is overspecified if you only want a vector direction
[15:18:46] <alex_joni> right.. yet sometimes you still need/want 6 in order to overcome singularities and special positions
[15:19:19] <cradek> could be, but I thought we were talking about degrees of freedom in the geometric sense, not a particular robot
[15:20:05] <cradek> on a 5 axis machine, rotation about the tool axis "slips" as you move the other rotaries
[15:20:30] <cradek> you can easily see it in my video when I move C (and the table keeps the penny under the spindle)
[15:20:48] <cradek> if you were sitting on the spindle looking down, you'd see the penny rotate
[15:21:28] <cradek> penny rotation is the DOF you don't care about since the tool spins anyway
[15:22:02] <cradek> (if the tool was a knife blade, you'd have to care about this)
[15:22:04] <alex_joni> ahh.. right
[15:22:16] <alex_joni> that's the DOF I do care about for welding usually ..
[15:22:25] <cradek> yeah I bet so
[15:22:28] <alex_joni> s/the DOF/the extra DOF/
[15:22:46] <alex_joni> * alex_joni found out the other thing is preventing "gimbal locks"
[15:22:56] <alex_joni> http://en.wikipedia.org/wiki/Gimbal_lock
[15:23:07] <cradek> yeah
[15:23:31] <cradek> if you're at the north pole, which way is west?
[15:25:32] <alex_joni> depends if it's summer or winter up there :)
[15:26:05] <alex_joni> also.. if it's the geographic or terrestrial north pole
[15:26:28] <alex_joni> or if it's the north magnetic pole (different thing altogether)
[15:27:33] <alex_joni> but the right answer is: "At the North Pole all directions point south."
[15:30:26] <alex_joni> but it's quite hard to say you are at the north pole.. did you know it moves around?
[15:30:46] <alex_joni> http://hpiers.obspm.fr/eop-pc/products/combined/C04plot.php?date=2&dimx=600&dimy=450&graphe=12&year1=1962&month1=1&day1=1&year2=2027&month2=12&day2=31&langue=1&SUBMIT=Submit+request (that's the position of the north-pole in the last ~40 years)
[16:29:24] <skunkworks_> dof?
[16:29:54] <skunkworks_> degrees of freedom?
[16:36:07] <jepler> yes
[16:38:06] <skunkworks_> jepler: thanks
[16:56:23] <alex_joni> cradek: I noticed 2 commits from you without a log message
[16:56:29] <alex_joni> and without CIA announcements
[17:07:12] <cradek> alex_joni: the file is on a branch only. nothing handles that very well
[20:00:59] <cradek> dangit, sherline website, tell me what taper is in the center hole of the rotary table
[20:01:17] <jmkasunich> probalby some morse
[20:01:58] <jmkasunich> did you check this page: http://www.sherline.com/dimen.htm
[20:03:59] <cradek> it's surely morse 0 or 1 isn't it
[20:07:29] <jmkasunich> you have anything with those tapers on it? stick it in and see
[20:07:57] <jmkasunich> oh, I just remembered a trick for measuring tapers
[20:08:26] <jmkasunich> find two steel balls that fit (ball bearings, etc) (two different sizes)
[20:08:39] <jmkasunich> drop one in, measure with a depth mic to see how far down it goes
[20:08:42] <jmkasunich> same with the other
[20:08:58] <jmkasunich> the geometry is left as an excercise for the student
[20:09:22] <jmkasunich> * jmkasunich is _so_ helpfull
[20:12:05] <cradek> well that's a good idea actually
[20:12:56] <jmkasunich> only if you have a good selection of steel balls
[20:13:25] <cradek> you could do something similar with hole gauge + height gauge
[20:13:34] <cradek> ... or something
[20:14:05] <cradek> yeah the half-ball hole gauges would work great for this
[20:14:18] <jmkasunich> I don't think so
[20:14:43] <jmkasunich> the shape isn't well defined - because of the taper, you aren't touching the hole at the fattest part of the ball
[20:14:50] <jmkasunich> a true sphere is needed
[20:15:10] <cradek> with the half ball ones, you would touch at the end of the hole gauge
[20:15:32] <jmkasunich> the end is rounded a bit (its not a knife edge)
[20:15:48] <cradek> well that's true
[20:16:05] <jmkasunich> I guess if all you are trying to do is figure out what you have it would work, if you were trying to accuratly measure you need to be _very_ picky
[20:16:18] <jmkasunich> because the taper is shallow, a few thou on diameter = many thou in depth
[20:16:28] <cradek> yeah
[20:16:38] <cradek> (you sure find that out the first time you try turning one)
[20:17:03] <jmkasunich> yeah, I don't think I ever have
[20:17:10] <jmkasunich> the only taper I've ever made was in a collet holder
[20:17:31] <cradek> just another .0005 to clean up the finish!
[20:18:03] <jmkasunich> thats when you grind
[20:23:28] <jmkasunich> * jmkasunich goes to HGR (Christmas time for John!)
[20:23:35] <jmkasunich> http://www.hgrindustrialsurplus.com/search-products/product-detail.aspx?id=10-301-057&searchtable=1&sortExpression=wbprice&SortASC=Yes&pageSize=50&currentPageIndex=0
[20:23:36] <cradek> whee
[20:23:40] <jmkasunich> this looks interesting
[20:23:58] <jmkasunich> and this
[20:23:58] <cradek> yes it does
[20:23:59] <jmkasunich> http://www.hgrindustrialsurplus.com/search-products/product-detail.aspx?id=30-389-022&searchtable=1&sortExpression=wbprice&SortASC=Yes&pageSize=50&currentPageIndex=0
[20:24:29] <cradek> 90k? stand back
[20:24:50] <jmkasunich> no clue about care and feeding of those things - might require oil mist lube, air bearings, who knows
[20:24:58] <jmkasunich> but it can't hurt to look eh?
[20:25:22] <cradek> yes, looks interesting
[20:25:33] <cradek> I think the fast ones are air (+ oil)
[20:25:56] <jmkasunich> I'll see if that "cord" is hollow
[20:26:29] <jmkasunich> anything you'd like me to check for?
[20:26:49] <jmkasunich> (under 100 lbs ;-)
[20:26:51] <cradek> ummmmm
[20:27:12] <cradek> boring head
[20:27:42] <jmkasunich> they have exactly one
[20:27:44] <cradek> (very unlikely I bet)
[20:28:01] <jmkasunich> with a morse (or maybe brown-n-sharpe) taper
[20:29:06] <cradek> yep that doesn't look very promising
[20:29:47] <jmkasunich> http://www.smalltools.com/product_details.asp?cat_id=139_12&prod_id=91557
[20:30:03] <jmkasunich> I haven't compared prices, this probably isn't any better than a catalog supplier
[20:30:40] <cradek> I think that's a chinese one that you can get for ~ $45
[20:30:57] <jmkasunich> small tools also has used, that might be promising
[20:30:59] <cradek> I might get one and see what it's like. might be good enough.
[20:31:32] <cradek> got some big tapered bearings to try to make a scara (or similar)
[20:31:49] <jmkasunich> you have the bearings?
[20:31:53] <cradek> yes
[20:32:31] <jmkasunich> http://www.smalltools.com/product_details.asp?cat_id=139_12&prod_id=124783
[20:33:58] <jmkasunich> well, I'm gonna head out
[20:34:01] <cradek> hm, it appears a coworker got a remote control helicopter
[20:34:04] <cradek> have fun
[20:37:34] <skunkworks_> havocheli?
[20:37:41] <skunkworks_> or a real one?
[20:37:51] <cradek> a little indoor toy
[20:40:59] <skunkworks_> yah - they are pretty fun after you get used to them.
[20:41:33] <skunkworks_> http://www.electronicsam.com/images/havoc/SIDE.JPG
[20:41:52] <skunkworks_> there are a bunch of companies making similar ones now.
[20:43:20] <cradek> yes it looks something like that
[20:44:41] <skunkworks_> Again - great work on your max.. that is so cool.
[20:46:24] <cradek> thanks
[20:54:45] <fenn> just need to make a wireless induction-powered boring head for your cnc
[22:23:47] <jmkasunich> well, the red "spindle" at HGR was a bust
[22:23:54] <jmkasunich> its actually some kind of slip ring assembly or something
[22:24:05] <jmkasunich> the wires rotate with the shaft
[22:24:34] <jmkasunich> and couldn't even find the other one (90K rpm)
[22:24:47] <jmkasunich> but I did get some good spindle bearings
[22:25:26] <jmkasunich> http://www.hgrindustrialsurplus.com/search-products/product-detail.aspx?id=60-108-951&searchtable=1&sortExpression=wbprice&SortASC=Yes&pageSize=50&currentPageIndex=0
[22:25:37] <jmkasunich> each of those has two pairs of angular contact bearings
[22:25:47] <jmkasunich> got two for $18
[22:26:47] <fenn> is that a useful taper?
[22:26:52] <fenn> in the spindle shaft
[22:27:08] <jmkasunich> its not a usefull taper
[22:27:38] <jmkasunich> consider it a hundred dollar (or more) kit of bearings with a handy carrying handle
[22:36:28] <jmkasunich> the spindle has a strongly spring loaded drawbar inside
[22:43:38] <jmkasunich> well I'll be dipped in shit - I think these might be HSK taper spindles
[22:47:14] <fenn> O.o
[22:55:37] <fenn> probably slightly worn but still good enough for government work
[22:56:01] <jmkasunich> only problem is that matching toolholders would cost an arm and two legs
[22:56:16] <jmkasunich> I've pretty much confirmed it - HSK-A32 taper
[22:56:39] <fenn> well, you could just get an er collet chuck
[22:59:56] <jmkasunich> sure, thats only $611 from MSC
[23:00:01] <fenn> heh
[23:00:17] <fenn> but you saved so much on the $9 spindle
[23:00:32] <jmkasunich> which was $9 because it needs rebuilt
[23:00:54] <jmkasunich> the repair tag indicates problems that would not affect the bearings
[23:00:56] <fenn> bah. just make some hsk toolholders on your cnc lathe :)
[23:02:06] <fenn> (for the record, i think hsk is a terrible concept)
[23:02:16] <jmkasunich> why's that?
[23:02:31] <fenn> it has to be perfect
[23:03:14] <jmkasunich> the tooling?
[23:03:19] <fenn> the toolholders
[23:03:43] <jmkasunich> the makers can make darn near perfect toolholders, and when they do they get results that are better than the older tapers
[23:03:47] <jmkasunich> so why not do it?
[23:04:40] <fenn> because its hard to make near-perfect things
[23:04:58] <jmkasunich> the people who make high end tooling can do it
[23:05:23] <fenn> tormach system doesn't require near-perfect dimensions on the taper and won't get stuck in the spindle after high speed runs
[23:05:28] <jmkasunich> and the fact that industry willingly pays $600 for a collet chuck tells me that they are gaining throughput or some other financial benefit from it
[23:05:44] <jmkasunich> HSK doesn't get stuck - that's one if its advantages
[23:05:56] <fenn> tormach will suck up into the taper though (hsk will not)
[23:06:11] <fenn> but it moves back down at least
[23:06:53] <jmkasunich> the fact that these are HSK makes me feel good about the bearings
[23:07:03] <jmkasunich> they don't put crap bearings on HSK spindles
[23:07:57] <fenn> oh, actually, tormach will not suck up into the spindle (what was i thinking?)
[23:09:33] <jmkasunich> all I need is a HSK to tormach adapter and I'll be all set!
[23:09:47] <fenn> actually, that's not as bad an idea as it sounds
[23:10:04] <fenn> you make a collet that fits the hsk taper, and draws your straight shank toolholder up against the spindle face
[23:10:50] <jmkasunich> that thought has occurred to me
[23:10:54] <fenn> maybe i should get some of those spindles
[23:11:04] <jmkasunich> the taper isn't very long, but it might actually be possible
[23:11:20] <fenn> what are the dimensions of HSK-A32
[23:11:44] <jmkasunich> http://www.schaublin.ch/catalogues/PO012-019.pdf
[23:11:53] <jmkasunich> that shows toolholder dims
[23:12:09] <fenn> thanks
[23:12:13] <jmkasunich> I had a spindle/clamp mechanism cutaway, lemme find that again
[23:12:59] <fenn> very shallow taper
[23:13:07] <jmkasunich> http://www.mmsonline.com/articles/100105.html
[23:13:22] <jmkasunich> yes, more like morse than CAT
[23:14:59] <jmkasunich> I was able to remove the "collet expander" and collet fingers pretty easily
[23:15:10] <jmkasunich> the amount of spring force inside this thing scares me a bit tho
[23:18:12] <fenn> well that article certainly cleared up some misconceptions i had :)
[23:18:31] <fenn> did not know the taper face expanded radially under spring pressure
[23:19:31] <jmkasunich> it would be slick as heck to be able to adapt one of these to take tormach style tools
[23:21:16] <jmkasunich> front bearings 68mm OD, rear bearings 62mm OD, 5.7" from front of front bearing to back of back bearing
[23:21:47] <jmkasunich> 11.5" overall, including drawbar stuff and a spline on the back
[23:35:12] <fenn> i dont suppose hgr does mail order.. would you consider picking me up two of those next time you are there?
[23:48:28] <jmkasunich> they do mail order actually, but they might try to rape you on shipping cost
[23:48:47] <jmkasunich> I can do it though, they'll be open (and Ill still be on vacation) between christmas and new years
[23:49:03] <jmkasunich> or you can call them
[23:49:30] <jmkasunich> they're asking 9.99 each, I paid 18 (plus tax) for two
[23:49:41] <jmkasunich> since they aren't crazy heavy they might ship reasonably cheap
[23:49:55] <jmkasunich> when I got a 120 lb transformer for cradek they tried to charge him $250 to ship it
[23:50:09] <jmkasunich> actual shipping when I shipped it was ~$65
[23:50:19] <jmkasunich> these are more like 10 lbs each
[23:53:08] <fenn> i'll call tomorrow and see
[23:59:42] <jmkasunich> tomorrow's saturday, they're closed
[23:59:59] <jmkasunich> they are open one saturday a month, I think its the 3rd one