#emc | Logs for 2009-10-14

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[00:06:17] <tom2> those small holes are now done with laser IF not too deep, but .3mm with 20mm depth are still edm'd.
[00:06:19] <tom2> the material may only be 5mm thick but you enter it at 10 degrees, which is hard on drills and increases cut depth a lot.
[00:07:00] <tom2> (well a shallow entry angle, not 10deg)
[00:07:34] <tom2> tom2 is now known as tom3p
[01:32:11] <andypugh> night all
[01:48:00] <skunkworks> logger_emc: bookmark
[01:48:00] <skunkworks> Just this once .. here's the log: http://www.linuxcnc.org/irc/irc.freenode.net:6667/emc/2009-10-14.txt
[11:11:37] <MattyMatt> does any one know stepper circuits? This one on http://www.aaroncake.net/Circuits/stepper.asp looks like it only uses half the coils at a time
[11:12:22] <archivist> thats known as unipolar and yes its not so good or powerful
[11:12:41] <Valen> easy though as a rule ;->
[11:13:04] <archivist> regard as the worst of stepper drivers
[11:13:24] <archivist> has no current control either
[11:13:25] <MattyMatt> that's the kind of steppers I've got tho
[11:14:10] <pjm__> morning
[11:14:26] <pjm__> or afternoon i mean
[11:14:28] <archivist> you can use steppers in many ways
[11:14:30] <pjm__> pjm__ is now known as pjm
[11:14:57] <MattyMatt> k, I'll keep looking :)
[11:15:12] <alex_joni> MattyMatt: get gecko's and be done with it
[11:15:17] <MattyMatt> I've seen one made from a ULN 2803 btw
[11:16:15] <MattyMatt> I simply don't have the cash. this is made from junk or nothing.
[11:16:50] <MattyMatt> it was my pile of dead printers that inspired me to start
[11:17:48] <archivist> some unipolar motors can be driven bipolar and you can use a higher voltage with pwm current control
[11:18:38] <MattyMatt> will those open-collectors melt if I try and use them as analog amps?
[11:19:32] <MattyMatt> I can guess the answer, so pwm it is.
[11:20:33] <MattyMatt> plan A is reprogram this printer board. it's 80188
[11:20:59] <archivist> which printer?
[11:21:31] <MattyMatt> and has 2x L6219
[11:22:08] <MattyMatt> olivetti JP190 or 150 I forget (I had both at one time)
[11:22:16] <archivist> liberate the useful, or cut tracks and connect to parallel port
[11:22:41] <archivist> ew I worked on Olivetti printer code
[11:22:41] <MattyMatt> I was thinking of doing the pwm with the cpu
[11:23:17] <archivist> were they the integrex badged colour ones?
[11:23:56] <alex_joni> too slow for that (pwm with the CPU)
[11:24:12] <alex_joni> get some L297/298 - that's pretty cheap
[11:24:24] <alex_joni> it does half stepping, and current limiting
[11:24:56] <archivist> all the work is done in the L6219 on that board
[11:25:11] <archivist> it has pwm etc
[11:25:27] <MattyMatt> ah ok, so I want to liberate those chips
[11:26:02] <archivist> or hack the board and connect to the pins on the L6219 for clock and dir
[11:26:20] <MattyMatt> other printer (where the fat stepper came from) has 4 transistors in a row, so I guess it's that simple bipolar design
[11:26:31] <archivist> it will probably be connected bipolar as it should
[11:27:15] <MattyMatt> My bro left a stash of veroboard at mommas. I never had so much :)
[11:27:24] <MattyMatt> I'll liberate the chips
[11:28:06] <MattyMatt> I may find another use for the cpu/ram/rom combo intact
[11:28:15] <archivist> I probably still have the ROM images from that printer
[11:30:42] <MattyMatt> no disassembly tho? I was going to disassemble the old one to find the stepper ports
[11:32:06] <archivist> at home I may still have the code, but we never had to go deep in the stepper code
[11:32:23] <MattyMatt> there's one glue chip doing the address decoding, so I'd need a few channels of circuit analyser
[11:32:34] <archivist> we bought in printers and modded them and resold
[11:33:45] <MattyMatt> 188 is a joke really. 386SX would be worth the effort, just
[11:34:12] <MattyMatt> but for $10 I could have a new ARM with more ram & rom inside it
[11:34:28] <archivist> I had to fix the borked commercial disassembler for that job
[11:36:50] <MattyMatt> lovely. integrex? I think the Tandy one I had was a rebadged one of them
[11:38:07] <MattyMatt> cgp 220 . I was quite fond of that even tho it was shit. I wrote overprinting progs to get more bits out of it and I even tried to interlace
[11:40:28] <MattyMatt> right. I'll short circut the L6219 to the parallel port. I do have a new dremalike, after all
[13:02:11] <skunkworks> http://imagebin.ca/img/KYDWmq1m.png
[13:03:24] <SWPadnos> tiny
[13:03:26] <SWPadnos> :)
[13:03:35] <archivist> smutty pic server?
[13:03:50] <SWPadnos> can't be, there's only 900G used
[13:06:10] <skunkworks> heh - I am really new to this..
[13:06:24] <skunkworks> I assumed the 900g used was the parity usage for raid 5
[13:06:45] <skunkworks> (linux side anyways.)
[13:08:56] <SWPadnos> do you have hot-swap working?
[13:08:59] <skunkworks> considering I have not gotten to the point that it is something I can copy files to..
[13:09:37] <skunkworks> I don't know. (well - I have not yanked a drive yet)
[13:11:19] <SWPadnos> I'd suggest doing that before copying loads of data to it
[13:11:25] <skunkworks> I haven't really found a good how-to yet. been peicing things togather from a few sources. Damn linux people!
[13:11:48] <skunkworks> heh - sure. This is more of a test to see how well it works.
[13:12:59] <SWPadnos> is that hmmm - RAID5 with only one parity drive?
[13:13:09] <SWPadnos> 8 drives with one for parity
[13:13:32] <SWPadnos> oh, it says RAID5 up top
[13:13:41] <SWPadnos> I'd suggets RAID6, and/or a hot spare
[13:15:03] <SWPadnos> yay! I got a new coffee grinder!
[13:15:06] <skunkworks> heh
[13:15:19] <SWPadnos> too bad it isn't one of the red ones, to match the mixer
[13:15:29] <SWPadnos> at least it matches the coffee maker
[13:28:01] <SWPadnos> hey skunkworks, do you have those atom boards in cases?
[13:28:46] <skunkworks> yes
[13:28:52] <SWPadnos> bummer :)
[13:29:13] <SWPadnos> I'll have about a dozen mini-ITX cases available, cheap
[13:29:23] <skunkworks> heh
[13:29:43] <SWPadnos> this one: http://www.mini-box.com/M300-LCD-Enclosure;jsessionid=0a01025a1f43149f276a577f4c948c5982b25627a9bf.e3eSbNySbxiNe34Pa38Ta38Ra3z0?sc=8&category=87
[13:29:51] <SWPadnos> $30 or so, plus shipping
[13:37:36] <skunkworks> wow - that is a good deal
[13:41:01] <skunkworks> SWPadnos: what did you end up doing?
[13:41:25] <MarkusBec> MarkusBec is now known as MarkusBec_away
[13:41:42] <SWPadnos> oh, we built custom endlosures that have the D945GCLF2, a small ethernet switch, and a separate control board
[13:41:46] <SWPadnos> enclosures
[13:43:05] <skunkworks> nice - did you solve the pausing problem?
[13:43:18] <SWPadnos> it's a network driver bug, which should be fixed in 2.6.30
[13:43:25] <skunkworks> wow
[13:43:41] <SWPadnos> you probably don't hit it, because it only crops up under heavy network traffic
[13:43:42] <skunkworks> you where able to patch it?
[13:43:56] <SWPadnos> no, I'll be testing that theory this week
[13:44:11] <SWPadnos> and I may upgrade the machines to Karmic anyway
[13:44:55] <skunkworks> yes - and I didn't do much heavy networking with ubuntu
[15:09:17] <jymm> ***** GOOD MORNING VIETNAM *****
[15:09:29] <jymm> SWPadnos: Karma CNC???
[15:13:11] <fenn> ubuntu karmic koala
[15:20:46] <jymm> Live on the bleeding edge and you WILL get cut!
[16:04:36] <skunkworks> karmic karmic karmic karmic karmic karmic chameleon....
[16:04:48] <SWPadnos> * SWPadnos slaps skunkworks
[16:04:54] <Valen> * Valen helps
[16:05:11] <Valen> when is karmic out? i have some systems that are in need of a refresh
[16:05:20] <SWPadnos> 10/27 or something
[16:05:31] <Valen> qawww man thats like for ever
[16:05:45] <SWPadnos> oh, 10/29
[16:05:49] <SWPadnos> https://wiki.ubuntu.com/KarmicReleaseSchedule
[16:06:05] <Valen> thats like forever and 2 days
[16:06:07] <SWPadnos> don't install the beta if you have an ATI video card
[16:06:17] <Valen> i hate ATI so i'm happy
[16:06:20] <Valen> but whats the go?
[16:06:22] <SWPadnos> I noticed this when I updated the alpha to beta
[16:06:41] <SWPadnos> the accelerated driver doesn't work with kernel 2.6.31
[16:06:48] <SWPadnos> it may today, but it didn't yesterday
[16:07:05] <Valen> hows the open source 3d driver coming
[16:07:16] <SWPadnos> no idea, I haven't looked at it in a while
[16:07:57] <Valen> should look at porting EMC to lucid ;->
[16:09:11] <skunkworks> http://imagebin.ca/img/G-yugm.png
[16:09:34] <Valen> you has lots of raidsors
[16:09:48] <Valen> 6tb worth give or take
[16:10:00] <Valen> whats it for other than sploding hdds ;->
[16:10:27] <skunkworks> in the future - file serving
[16:10:35] <skunkworks> right now - playing.
[16:11:13] <Valen> what size disks?
[16:11:18] <skunkworks> 1tb
[16:11:38] <Valen> nice
[16:11:42] <skunkworks> * skunkworks was just excited he actually got it mounted.
[16:11:45] <Valen> thats alot of pr0n
[16:11:59] <skunkworks> we actually have 3 total here. (2 are on windows servers)
[16:12:24] <Valen> 3 pr0ns?
[16:12:43] <skunkworks> not that expensive - a bit over 1k for drives/case/esata card.
[16:16:44] <Valen> suggestion for you, while its all in your mind
[16:17:03] <Valen> practise failing and rebuilding the drives now before you have anything on it
[16:17:23] <Valen> and practise doing it with a different drive (ie a different size)
[16:17:46] <Valen> then when you have your process sorted, write it out ;->
[16:18:29] <Valen> oh yeah, and there is something you can do to get mdadm to spit out a file with the array configuration on it, get that
[16:18:45] <Valen> and the mapping between the uuid's and the /dev/sdfoos you have currently
[16:20:11] <skunkworks> yep - After I copy some test files to it - I am going to plan on removing drives and maybe even transfer it to a differnt system to paly
[16:20:13] <skunkworks> play
[16:30:20] <Valen> oh yeah, the system transfer is a biggie
[16:30:29] <Valen> that can be a bitch and a half to get working
[17:00:40] <skunkworks> The actual os install isn't raid...
[17:01:18] <skunkworks> I don't really think it would work with these boxes anyways. at boot time you can only see 2 of the drives (1 on each esata channel)
[17:01:28] <skunkworks> I figure the os isn't really a biggie.
[17:02:38] <skunkworks> that way it should be pretty hardware un-aware. just plug the esata card into another computer and scan for them with mdadm.
[17:02:47] <skunkworks> atleast that is what is in my little mind..
[18:14:30] <fenn> dunno if anyone cares but reprap v 2.0 "mendel" has been released-ish http://objects.reprap.org/wiki/RepRap_Version_II_"Mendel"
[18:15:42] <fenn> now uses roller bearings and cheaper nema-14 steppers
[18:19:03] <skunkworks> neat
[18:31:54] <MattyMatt> I'm considering preprap possibilities on mine. plastic extrusion
[18:32:48] <MattyMatt> I had a grease gun once that woulda been perfect with a brass washer instead of the leather one
[18:35:48] <MattyMatt> I've just been to the local auction. I thought if I got the 12" table saw I'd make my router frame out of wood, and if I got the arc welder, I'd make it from steel
[18:36:01] <MattyMatt> I got both
[18:36:24] <AchiestDragon> well couple of tips on eather
[18:37:01] <archivist> I have no welding or wood in my mill :)
[18:37:03] <MattyMatt> don't let momma know about either of them?
[18:37:40] <AchiestDragon> if you make the router out of wood you don know that wood tends to expand and shrink over the year , so can cause problems when used with metal parts
[18:38:23] <MattyMatt> yeah I was there looking for oak furniture originally
[18:38:25] <AchiestDragon> if you weld it remeber to make all the critical allignment adustable to allow for welding deformation
[18:39:02] <MattyMatt> yeah I'll make panels out of tubes, and bolt them together
[18:39:33] <AchiestDragon> you can weld together a square frame and no mater how acurate you weld it you may find that its a mm or so out once cooled down
[18:39:56] <MattyMatt> even if all members are clamped?
[18:40:04] <archivist> yes
[18:40:36] <archivist> warpage with welding takes some controlling
[18:40:39] <AchiestDragon> i prefer welding but you have to desgin in ajustments to compencate for any inacuracy in the finished frame
[18:40:41] <MattyMatt> right I'll bear that in mind.
[18:41:28] <archivist> pros clamp , tack and only then weld
[18:41:35] <MattyMatt> I made custom bike frames in holland with an arc welder, but they didn't last long :)
[18:42:23] <AchiestDragon> seen a couple thats started projects on cnc.com where they thought welding rails would be fine ,, but did not allow for adjustment , so the whole thing is scrap from the point they spot its out
[18:42:33] <tom3p> the reprap link sez "There is currently no text in this page, you can search for this page title in other pages or edit this page."
[18:43:20] <tom3p> oh, add the space and quoted string on end, its ok
[18:43:27] <tom3p> with quotes
[18:45:55] <tom3p> boy those guys aren't worried about weldments
[18:46:15] <tom3p> lego? not, mechanno? almost
[18:46:45] <MattyMatt> plastic meccano, or fischer teknik
[18:47:38] <MattyMatt> plastic can be quite good, but the reprap stuff looks like polythene
[18:48:48] <tom3p> hdpe?
[18:50:42] <AchiestDragon> http://www.whipy.demon.co.uk/Cnc1.jpg rough looking but the welded frame is nice and strong ,, think you can see it was just thrown together and made it so i could get away with quite big errors and still allign it
[18:52:20] <MattyMatt> that looks so much better than a wooden one, I must confess
[18:52:30] <AchiestDragon> actualy works well only main problem was the x axis adjusters could of done to be doubled up as theres a bit of flex on them under full load
[18:53:33] <MattyMatt> does your table overhang the front?
[18:53:46] <AchiestDragon> given that i used stock m10 threaded bar as leadscrews
[18:54:14] <MattyMatt> m8 for me. I misread the list and thought it was 1mm pitch
[18:54:16] <AchiestDragon> not by mutch ,,, its a 24" by 12" travel
[18:54:29] <AchiestDragon> m10 is 1.5mm pitch
[18:54:53] <MattyMatt> fine thread m8 is 0.8 or 0.75 iirc
[18:54:58] <AchiestDragon> makes it a bit slow on steppers
[18:55:30] <MattyMatt> I thought the gearing would help my undersized steppers. only loss is speed
[18:56:14] <AchiestDragon> otherthan i welded the nuts to brackets and made simple antibacklash mountings means that i was looking to do a total fresh one to replace and try to make a better looking job of it
[18:56:41] <AchiestDragon> rather than upgrade them to proper leadscrews
[18:57:08] <MattyMatt> I'm going to use a split brass nut I think
[18:57:43] <MattyMatt> with a quick release handle so the table can intude into gangways
[18:57:54] <MattyMatt> intrude
[18:58:09] <MattyMatt> on the mk3
[18:58:56] <AchiestDragon> 2 nuts one fixed the other held so it does not rotate but would float allong the axis ,, held appart from the other by a spring seems to be an efective antibacklash
[18:59:03] <MattyMatt> ah I'll finish the mk1 first. I've got seasoned wood just needs straightening
[19:01:16] <MattyMatt> not enough to do it all in oak tho. a couple of fine cabinets to hack up would be nice
[19:01:19] <AchiestDragon> merchantdice on flebay has some nice trapizoidel leadscrews in 8mm ,, he also has the nuts the nuts allone he sells for about £30 for 3 not a bad price and worth the expence
[19:01:59] <MattyMatt> yeah I'll upgrade later
[19:02:46] <AchiestDragon> yea mistake i made was not to allow for the upgrade when i built that
[19:02:51] <MattyMatt> I code my screw length as 600mm because that seems to be a standard size for real leadscrews
[19:03:04] <MattyMatt> ^chose
[19:03:22] <AchiestDragon> the other problem i seem to have with most of the router designs are the rails
[19:03:54] <AchiestDragon> use the ones with the C bearings and 16 or 20 mm rails supported allong there lenth
[19:04:23] <AchiestDragon> the 20mm end supported rails flex way too much
[19:04:58] <MattyMatt> I think 2 pairs of these shelf sliders, at right angles and opposing directions (only one pair 'fully' extended) will do nicely
[19:05:59] <MattyMatt> for wood carving, anyway
[19:06:08] <AchiestDragon> i used 20mm rails suported in a bit of angle iron welded to unistrut even that has some flex 20mm rail end supported alone would not do at 600mm long
[19:06:43] <MattyMatt> yeah I wouldn't try it
[19:07:16] <_tarzan_> what are antibacklash mountings and why are they needed?
[19:07:32] <MattyMatt> I'm gad to know homemade supported rail works tho
[19:07:55] <AchiestDragon> _tarzan_: you got a nut and bolt there about 13mm /1/2"
[19:08:31] <AchiestDragon> then hold the bolt and with the nut lose see how much slack there is without turning eather
[19:08:58] <AchiestDragon> and not tightend up
[19:09:12] <MattyMatt> and a bit worn, ideally
[19:09:56] <AchiestDragon> yea idealy one where you can spin the nut and get it to freely run up the bolt , , well the backlash is the play on that
[19:10:59] <MattyMatt> metric thread would be almost acme shape if you ground it down a bit
[19:11:32] <AchiestDragon> seen it as high as 3mm on some nuts and bolts ,, but on a leed screw that play would lead to positional inacuarcys ,, hence the backlash value
[19:12:02] <MattyMatt> ah so emc tracks which way you're coming from?
[19:12:10] <AchiestDragon> metric thread is not too bad but its still a bit tight 1.5mm a turn is low for a leadscew
[19:12:28] <AchiestDragon> would rather have 4mm per turn
[19:12:48] <tom3p> he asked whats an antibacklash mounting, still thiking about that, not a nut, he said mounting. maybe he means nut but...
[19:13:07] <MattyMatt> 5mm ballscrews in the woodcarver/extruder model, evetually
[19:13:28] <tom3p> _tarzan_: you mean nut or mounting? describe what you mean
[19:13:49] <AchiestDragon> http://2.bp.blogspot.com/_pFOm7tEWWu4/SeGOgrP03cI/AAAAAAAABoU/OK7Uo9dK2ak/s400/Antibacklash+nut+01.JPG
[19:14:07] <MattyMatt> the monting would be the spanner that stops the floating nut turning
[19:14:52] <MattyMatt> or even the kind that presses to half-nuts in
[19:17:25] <AchiestDragon> _tarzan_: http://www.machinetoolhelp.com/Repairing/What_is_backlash.html describes backlash
[19:17:29] <MattyMatt> someone wrote that he was getting 0.003 accuracy with a plain 1 inch rod connector (m6 iirc), so he ditched his antibacklash nut because the friction was a problem
[19:18:12] <MattyMatt> but I suppose you need to start wearing it all out before you care
[19:20:00] <AchiestDragon> yea ,, although had some that are supposed to be engineers expect that you can get less than a thou from a normal nut and bolt ,, but fail to realise that in real world the bronse nut expands at a diferent rate to the carbon steel leadscrew so you cant machine it that close
[19:20:30] <AchiestDragon> so you have to make the nut slack and use antibacklash to compencate
[19:20:45] <MattyMatt> ah. I was thinking of a brass nut
[19:20:56] <AchiestDragon> same with brass
[19:21:26] <AchiestDragon> eather would be more suitable than steel to steel for wair
[19:21:49] <archivist> compensating backlash in software is a mugs game, get the hardware right
[19:21:52] <MattyMatt> you could make it like a formula 1 car. heat the nut with a blowtorch before starting every morning
[19:23:06] <AchiestDragon> yea you can only compencate in software so much but it wont help the machine jitter problems
[19:24:22] <MattyMatt> I'm considering making machine a machine read a vernier
[19:24:39] <MattyMatt> with a cheap webcam
[19:25:54] <MattyMatt> absolte feedback, directly off the table
[19:26:55] <MattyMatt> the cheapest webcams have fixed lenses that won't focus that close tho
[19:26:57] <AchiestDragon> seems to think theres better ways to get a more acurate reading
[19:28:09] <AchiestDragon> a optical mouse sensor although small image resolution has its focus about right for 0.01" or better
[19:28:14] <MattyMatt> gray code, but you'd have to make the scale accurate
[19:29:15] <AchiestDragon> just dust and dirt starts to be a big issue , especialy if loose and moving arround like wood dust particles tend to
[19:29:20] <archivist> please forget optical mice
[19:29:55] <archivist> by that I mean the camera sort, not the wheel sort
[19:30:08] <AchiestDragon> one of the main problems i used to have to fix on big plotters was paper dust build up in the optical encoders
[19:30:27] <archivist> the camera type only detect movement, not amount
[19:31:14] <celeron55> it does detect amount but not accurately
[19:31:16] <celeron55> of course
[19:31:19] <AchiestDragon> archivist: would be the same with any camara method
[19:31:33] <MattyMatt> unless it could read the numbers :)
[19:31:41] <_tarzan_> AchiestDragon:antibacklash mountings and why are they needed? backlash may not be bad on machine tool
[19:33:19] <tom3p> cutter could grab ( climb ) into backlash and break tool., at least trash the work
[19:33:42] <AchiestDragon> MattyMatt: but the resolution you get on a cam even in macro would not be as high as you think
[19:33:58] <MattyMatt> well it's a cheap hardware experiment. I'm screwing a steel/alu ruler to my table and making a vernier anyway
[19:34:04] <AchiestDragon> its not just the numbers but the diference in the pointer positions
[19:35:17] <AchiestDragon> if you got a 1mm scail and thats half the vertical screen size between 1mm points then your only going to get a 100th of a mm max acuracy
[19:35:24] <MattyMatt> ideally the camera would be zoomed close enough to see the ticks on the ruler, and the numbers and the vernier. 320x240 would be fine for that
[19:35:40] <MattyMatt> 100th mm is plenty for me
[19:35:49] <_tarzan_> MattyMatt: backlash makes problems on steppers?
[19:36:03] <MattyMatt> no, on the leadscrew & nut
[19:36:14] <AchiestDragon> given that most cams only have a 240/2 usable res as there usualy and interlaced image
[19:36:16] <archivist> backlash is always a problem
[19:36:29] <MattyMatt> the screw can reverse a little bit before the nut responds
[19:36:53] <tom3p> not that they notice ;) theres usually no feedback on stepper systems. the work would suffer, the stepper would not
[19:39:14] <_tarzan_> archivist: which kind of problems happen with backlash?
[19:39:19] <MattyMatt> as I only have one usable motor so far, getting a relable 0.01mm sensor would be a bonus
[19:39:47] <archivist> _tarzan_, poor work and broken tools in the machine
[19:39:55] <MattyMatt> that'd let me use servos of some sort, probably DC motors
[19:40:00] <tom3p> _tarzan_: take a look http://www.imwsrv.com/cncmachwhat.pdf
[19:40:12] <archivist> _tarzan_, eg a round hole becomes oval
[19:40:50] <MattyMatt> 0.01mm is plenty accurate enough for woodwork
[19:41:20] <MattyMatt> overkill even. I'm aiming for 0.1mm
[19:41:23] <archivist> accuracy and play are separate problems
[19:41:44] <MattyMatt> accurate sensing would eliminate play
[19:42:02] <tom3p> yeah 0.01mm its smaller than the lines on those sticks carpenters carry around
[19:42:02] <archivist> no , not when climb milling
[19:42:39] <archivist> emc will happily climb mill and smash tooling
[19:43:03] <AchiestDragon> no play would cause jitter so a straigt edge may end up waving up and down over its lenth if you encounter a knot in the wood that makes it a bit harder on the machine
[19:44:10] <MattyMatt> yeah play in the head is the big worry
[19:44:30] <archivist> hard teaching climb milling to noobs, the machine grabs the work and moved the table by cutting force
[19:45:01] <MattyMatt> I think I will make a 100% steel Y motion, or use this ballscrew motion one I won on ebay (no word from them yet, although I've paid them)
[19:45:06] <tom3p> wow, machines that bend at wood knots, maybe that tinkertoy syrup pouring reprap is good enuf
[19:45:26] <MattyMatt> Z motion I mean
[19:45:57] <archivist> looking at some of the spindly machines , I would be careful what wood I put on them
[19:46:19] <tom3p> nerf machines
[19:46:20] <AchiestDragon> tom3p: if its oak your machining on a plywood router then it would be expected i guess
[19:46:46] <AchiestDragon> and probablay unavoidable
[19:46:57] <archivist> steel machine made to a poor design will be as bad
[19:47:05] <AchiestDragon> yea
[19:47:45] <MattyMatt> inch thick oak planks looks acceptable for the gantry uprights. solsylva's design
[19:47:56] <archivist> test dti against the spindle and dti base on table, push spindle
[19:48:00] <AchiestDragon> the usual ply framed router design would say there ok for balsa wood
[19:48:19] <tom3p> doubt dti in toolbox
[19:48:23] <MattyMatt> I see more mdf than ply
[19:49:04] <MattyMatt> and people use chipboard for floorboards, god help them
[19:49:19] <AchiestDragon> would not recomend mdf ,, seems that its a carsinagenic , so its worth avoiding machining if you can
[19:49:20] <MattyMatt> ..when it gets wet
[19:49:51] <MattyMatt> yeah they use formaldehyde to make chipboard, I presume the same for mdf
[19:50:16] <MattyMatt> but I guess ply is just as bad
[19:50:22] <AchiestDragon> the safty guys now insist that you have a face mask at least if working on it bacause of the dust helth problems it gives
[19:50:50] <AchiestDragon> its not so much the wood content is the resin they used to bond it
[19:51:09] <MattyMatt> any stout timbers I get will be cut from telegraph poles on my new table saw. they are full of creosote & bitumen
[19:51:24] <MattyMatt> you can't win
[19:52:00] <AchiestDragon> you need to ensure that you have good dust extraction /collection on the machine
[19:52:08] <MattyMatt> I got about 1000 rods with the arc welder. there's enough flux on them to poison an army
[19:53:31] <MattyMatt> 350 per box, 2 nearly full boxes
[19:53:51] <AchiestDragon> we have the unfrotunate problem of having a mdf factory in the town here ,, aparantly the number of residents with respiritary problems here is way higher than elsware in the aria
[19:54:48] <AchiestDragon> they make chipboard and ply also
[19:55:21] <fenn> MattyMatt: oak will warp with changes in humidity and temperature
[19:55:40] <AchiestDragon> all wood does
[19:55:45] <MattyMatt> yeah, and with age
[19:56:07] <MattyMatt> for about the first 400 years anyway, with oak :)
[19:56:11] <fenn> ... so don't make a machine out of it
[19:56:18] <MattyMatt> after that it's sound
[19:57:01] <MattyMatt> yeah I'll make the frame from square tube, I think
[19:57:19] <AchiestDragon> after it gets to that age you probalbay find its fallen apart dew to woodworm
[19:57:27] <MattyMatt> or round even, I don't mind cutting 3d curves
[19:58:20] <MattyMatt> I got an A for Engineering Drawing, even tho the bastards wouldn't let me in the workshops after the 3rd year
[19:58:36] <MattyMatt> because I got too many A's
[19:59:01] <AchiestDragon> round is better at stopping it twist on the lenth , but it will flex more allong the lenth , square and its the other way arround
[19:59:37] <MattyMatt> ah cool, so a careful mix is best
[19:59:48] <AchiestDragon> yea
[20:01:02] <MattyMatt> so square for the gantry uprights and table frame, with round triangulation pieces
[20:01:12] <MattyMatt> sounds good to me
[20:01:48] <AchiestDragon> and if using say 2" square go for 5mm thick rather than the 2.5mm stuff
[20:02:16] <MattyMatt> I'll use what appears in skips
[20:02:38] <MattyMatt> I can weld bike frames, so I've had practice on thin walls :)
[20:03:02] <MattyMatt> I could arc weld gas pipes if I had to, with 700 rods
[20:04:22] <AchiestDragon> 40mm square 2.5mm thick steel new is £14.50 for a 7.6m lenth from FWB if theres on local to you they will deliver for free also , its cheap enough to buy new than it is to set about cleaning paint of a bit you get from the scrap
[20:05:15] <AchiestDragon> although you may have to order a few lenths for them to deliver
[20:05:27] <MattyMatt> my friend bought a MIG when he was younger and keener, but he's never even put a plug on it. it's pristine. hopefully seeing me welding will spur him on
[20:07:07] <MattyMatt> when he sees my sputter beads on his new garage roof, he'll break it out of storage
[20:07:09] <AchiestDragon> the mig i have hast to be one of the most usefull power tools i use second to the drill
[20:09:12] <MattyMatt> I bought some 19" rack kit too, for a quid. an 8 port KVM, a nice 16 port 10/100 switch, and 2 useless 10Mb hubs on useful trays
[20:09:28] <MattyMatt> imagining a house full of metal reminded me of that :)
[20:11:31] <AchiestDragon> well got to fix kildets ps2,, he left a chocice on top of it ,, it melted and ran inside the workings
[20:11:48] <MattyMatt> lovely
[20:12:01] <AchiestDragon> blew the lazer ,, but thankfully did not make to big a mess of the rest
[20:12:15] <MattyMatt> just? is it still liquid?
[20:12:35] <archivist> wash
[20:12:51] <AchiestDragon> got it all cleend out some time ago , only just got a replacment lazer
[20:22:59] <MattyMatt> I paid 30 quid for the table saw, but I reckon it'd fetch more than that on fleabay if momma freaks out or insists it lives outside. 12" blade, what looks like a 1/2 hp motor, 2x3 table
[21:10:11] <jymm> SWPadnos: ping
[21:16:04] <AchiestDragon> MattyMatt: the pic of that my old machine the table does not overhang more than about 20mm just the angle of that pic does not make the sliders look as long as what they are ,, the sliders on that axis are 700mm long with a 340mm table on that axis
[21:19:48] <AchiestDragon> ie http://www.whipy.demon.co.uk/dscf2312.jpg the stainless steel bar is 700mm long 20mm dia the bearing piece of angle is 350mm long shame i dont have a pic of it from the side
[21:26:33] <AchiestDragon> and from experiance yea mamas can be that way ,, theres sort of a cure its to get your own place ,, but you then find it soon gets to the stage where you run out of space to put things like i still have a cnc machine trying to do an impression of a coffee table in the front room as theres noware else for it atm
[21:31:11] <jymm> AchiestDragon: What are you fabricating with that?
[21:32:08] <AchiestDragon> na it was one i though together to try a design , not got arround to dismantleing it and returning it to scrap yet
[21:32:28] <AchiestDragon> seems to make quite an interesting coffee table though
[21:32:44] <jymm> Ah
[21:33:10] <jymm> You welded galvanized? hopefully outdoors
[21:33:18] <AchiestDragon> yea
[21:33:51] <jymm> Yeah you welded, or outdoors, or both?
[21:34:15] <AchiestDragon> both ,
[21:34:19] <jymm> k =)
[21:39:11] <AchiestDragon> took a week to make the steel machine working only with hacksaw electric drill mig welder and basic hand tools
[21:40:18] <jymm> is it square/true?
[21:40:28] <AchiestDragon> made my own simple clamps 2 bits of angle iron with some holes for bolts to clamp the bits as i welded
[21:41:31] <AchiestDragon> i allowed for +-10mm for allignment ,, doubt theres a square edge on the welding but the machine alligns fine
[21:41:39] <jymm> heh
[21:42:05] <jymm> I was just going to say if the welded table is true, then save it.
[21:42:45] <jymm> You're approach is novel, but doesn't allow for adjustments (last minute tweeking).
[21:43:06] <jymm> But then, I have no clue what you were going to fabricate, so that might not matter at all.
[21:44:04] <AchiestDragon> na would need to hack some bits to rework for proper leadscews , the x axis adjustments could do with doubling up as theres a bit of flex on the lenth , but not a problem working with wood
[21:44:36] <AchiestDragon> realy was hopeing to do aluminum on it but theres just a bit too mutch flex on the rails for that
[21:45:12] <AchiestDragon> it drills aluminum fine but not good enough to mill it with aceptable results
[21:45:22] <jymm> http://www.8020.net/
[21:45:41] <jymm> oh, I misunderstood what you said. nm =)
[21:46:14] <archivist> AchiestDragon, add webbing to add stiffness
[21:46:24] <AchiestDragon> on that rail assembly i would realy want to add a lenth of 40mm by 20mm by 5mm thick box to stop the flex
[21:46:53] <AchiestDragon> as well as the angle iron and unistrut and the 20mm stanless bar
[21:47:09] <jymm> archivist: streched steel?
[21:47:32] <AchiestDragon> im still supprised how much flex there is in that combination over the lenth
[21:48:21] <archivist> web a sheet of metal to fill a corner often a rh triangle
[21:48:40] <archivist> long thin is very bendy
[21:49:20] <AchiestDragon> the x axis is only 800mm
[21:50:38] <AchiestDragon> although it was my 2nd attempt at a cnc
[21:51:20] <AchiestDragon> the first attempt was just using unistrut bolted together ,, but the bolts tend to vibrate lose and it was a wobbly machine
[21:52:14] <MattyMatt> I thought you could weld SS with a MIG
[21:52:42] <AchiestDragon> you can with the right gas and wire
[21:53:03] <MattyMatt> and the right bit of handy SS angle, I suppose
[21:53:26] <AchiestDragon> but i use gassless wire as its cheaper than std wire and co2
[21:53:34] <jymm> http://www.youtube.com/watch?v=50SEmXDh6Bw&feature=player_embedded#
[21:54:37] <AchiestDragon> getting co2 or argon is not easy for home use unless you go for the small poxy bottels that seem to last no time and cost a fortune
[21:55:40] <archivist> brewery/pub bottles
[21:56:00] <AchiestDragon> it was £60 for a refill and £200 a year for rental of the bottle last time i got the prices from boc but they wont deal with home users ,, only registered business useres
[21:56:47] <andypugh> I have an account with Air Liquide, no need to be a business.
[21:57:44] <AchiestDragon> gassless wire costs about £35 for a 5kg roll about double normal wire but still works out cheaper since you dont have the bottles to worry about ,, saver for storage and transport also
[21:58:13] <andypugh> Does anyone here read the mailing list?
[21:58:25] <AchiestDragon> seen one of thoes bottles blow ,,, ploughed though 3 thick brick walls and ended up burried in an embankment
[21:58:31] <archivist> yup plenty do
[21:58:59] <andypugh> Have my messages about speed control pots sitting at +100V been getting through?
[21:59:14] <MattyMatt> 60 quid for a refill seems a bit steep. you could get butane cheaper and run it through a fuel cell
[22:00:10] <andypugh> I seem to be paying £25 per quarter for rental of my Argon
[22:00:32] <archivist> andypugh, you can always view the archive its online
[22:00:33] <andypugh> I think a fill is £35, +£35 delivery if you don't have a car...
[22:00:53] <andypugh> Goos point archivist
[22:02:10] <archivist> if it was mid thread then I may have missed it/them
[22:02:15] <AchiestDragon> the last 5kg roll of wire i got will be running out i think next year if i have another big welding project ,, but the last roll has lasted me 3 years so far ,,, not like i am doing a masive amount of welding to justify a bottel rental
[22:02:39] <andypugh> I have mentioned it three time now I think, no hint that he has checked
[22:02:42] <MattyMatt> depends on the bottle size, but I'm thinking those 4 ft tall ones on a trolley
[22:03:01] <MattyMatt> these 700 welding rods will keep me happy
[22:03:40] <AchiestDragon> yea BOC cost was £60 last time i was given a price
[22:03:46] <AchiestDragon> that was 5 years back
[22:04:06] <AchiestDragon> and guy was complaining about the rental charges also
[22:04:12] <MattyMatt> I need one of those LCD shutter faceplates. this one came with a plastic one with a handle
[22:04:48] <andypugh> You can pick up auto helmets for about £25 on that eBay.
[22:04:50] <AchiestDragon> may have been the cost for the acetaline
[22:04:59] <MattyMatt> yep
[22:05:02] <andypugh> And they are the best invention ever, they free up a hand.
[22:05:10] <AchiestDragon> yea
[22:05:22] <MattyMatt> and they let you see where you're poking the rod
[22:05:26] <archivist> andypugh, yes
[22:05:26] <andypugh> And mean no more perfect beads an inch to the right of the joint
[22:05:35] <MattyMatt> I assume, I've only done it the hard way
[22:05:48] <AchiestDragon> theres a guy at the local car boot you can get the gaunlets for £1 per pair
[22:06:29] <MattyMatt> wilkos have some cheap enough
[22:07:10] <andypugh> Yeah, my warning is three times in that thread, and no acknowledgement. If ye blows up his Gecko and VSD then I did my best.
[22:07:18] <AchiestDragon> wilkos ,, :) the place that sells you plastic buckets that you may be able to use twice before they break or shatter
[22:08:05] <MattyMatt> they are one of the poshest shops here now
[22:08:28] <archivist> you can take a horse to water but you cant make him drink
[22:08:31] <MattyMatt> we've got b&m, home & bargain and poundstretcher too now
[22:08:56] <MattyMatt> no proper tool shops whatsoever tho
[22:09:00] <AchiestDragon> spoiled for choice on low qualaty goods then
[22:09:19] <MattyMatt> it's our fault for voting labour
[22:09:52] <andypugh> I think that he is assuming that opto-isolated means galvanically isolated.
[22:09:59] <AchiestDragon> still need to find a place that sells a good bucket rather than having to pay £1 for one each time i need one
[22:11:02] <MattyMatt> buy 5 next time
[22:11:13] <AchiestDragon> my kids sandcastle bucket is stronger than those cheap ones they sell
[22:11:43] <AchiestDragon> would rather pay £10 for one that will last
[22:12:00] <MattyMatt> I spotted my black buckets under my Best Friend's old double garage door
[22:12:01] <AchiestDragon> problem is finding somware that sells them
[22:12:27] <andypugh> http://www.diy.com/diy/jsp/bq/nav.jsp?action=detail&fh_secondid=9375448&fh_view_size=10&fh_location=%2f%2fcatalog01%2fen_GB&fh_search=tub&fh_eds=ß&fh_refview=search&ts=1255558422374&isSearch=true
[22:12:31] <MattyMatt> I doubt they'll bounce back from that
[22:14:21] <andypugh> http://www.safety-marine.co.uk/Outboard-Engine-Accessories/P5206S28/7L-Rubber-Bucket.htm
[22:14:33] <AchiestDragon> weee major memory leek causing system crash ,,, been expecting that all day
[22:15:28] <andypugh> I think I have a suitably expensive bucket for you
[22:15:30] <andypugh> http://www.manufactum.co.uk/Produkt/193786/1443629/RubberBucket.html
[22:15:33] <AchiestDragon> still not managed to catch the app causing it though
[22:15:35] <andypugh> Tough as old tyres
[22:16:46] <AchiestDragon> yea but cant do this with it http://www.urbanjunkie.co.uk/shopimages/products/extras/Fire bucket BBQ 4503.jpg
[22:17:06] <AchiestDragon> dam link with spaces in
[22:17:25] <MattyMatt> old tyres, now there's a plan
[22:17:55] <AchiestDragon> http://www.urbanjunkie.co.uk/product.php/1116/0/fire-bucket-barbecue
[22:19:38] <AchiestDragon> actualy though the old buckets like that are what i would go for ,, the newer ones tend to be too thin and rust away ,, the rubber ones tend to perish and not good if using near welding
[22:20:09] <AchiestDragon> same with the plastic ones
[22:24:48] <andypugh> You could machine your own stainless steel buckets from solid
[22:25:04] <AchiestDragon> now that seems like a plan
[22:25:59] <andypugh> Maybe cheaper than buying one: http://www.ascott-dairy.co.uk/acatalog/Stainless-Steel-12-litre-Bucket-MK62.html
[22:32:20] <AchiestDragon> well 320433764984 just got one
[22:35:37] <AchiestDragon> see if it fairs up any better than the others
[22:35:52] <MattyMatt> stainless isn't much kop for not splitting
[22:36:36] <MattyMatt> I broke my friend's SS spade with the first dig
[22:37:11] <AchiestDragon> not ss its a galv steel one i just got £8.99
[22:37:30] <AchiestDragon> +4.45p&p
[22:37:48] <MattyMatt> that what I want for a funace
[22:38:45] <MattyMatt> it shouldn't get hot enough to give off zinc fumes
[22:39:34] <AchiestDragon> well amongst usual tasks like washing car etc its good to have one filled with water while welding ,, its not fun when you stop welding to find that the garden arround you is burning away quite happly
[22:39:48] <MattyMatt> sand if you please
[22:40:07] <MattyMatt> ater + arc = no thanks I'd rather burn
[22:40:11] <MattyMatt> ^w
[22:41:13] <andypugh> Low voltage, is arc
[22:41:37] <AchiestDragon> usualy have a washing up liquid bottle filled with water ,, its good for puting out any paint that chatches fire on the stuff you are welding
[22:42:30] <MattyMatt> yeah I wouldn't want sand in my metal pools
[22:42:45] <AchiestDragon> water pistols are good for that also ,, but finding them after kidlet has seen them becomes imposible
[22:43:26] <MattyMatt> loads of houshold products come with a free water pistol now
[22:43:54] <MattyMatt> window cleaner etc
[22:43:58] <AchiestDragon> yea
[22:44:34] <AchiestDragon> but better with a jet of water rather than a fine mist
[22:45:06] <MattyMatt> loosen the nozzle
[22:45:47] <MattyMatt> poke a pin in to widen it for a fatter jet
[22:46:08] <MattyMatt> but just unscrewing it gives you a good jet
[22:47:09] <AchiestDragon> the other one is its amazing how many products make good fire starters , like wd40 or hairspary
[22:47:15] <jymm> So instead of just a Class B fire, you're going for a Class C fire.... nice.
[22:47:30] <MattyMatt> a bit of antifreeze would make it a bit less rust-forming, and makes it too poinous for kidlet to touch
[22:48:23] <MattyMatt> ah, but it would look & smell like window cleaner, so you'd end up melting you window frames
[22:48:45] <MattyMatt> no that's brake fluid
[22:49:17] <andypugh> Antifreeze is good for you
[22:49:18] <jymm> SWPadnos: You should enjoy this... http://www.youtube.com/watch?v=50SEmXDh6Bw&feature=player_embedded#
[22:49:59] <jymm> Yeah, nice and sweet so the dog/cat can lick it and be poisoned.
[22:54:04] <SWPadnos> jymm, that's fairly insane
[22:54:30] <andypugh> Did you see the link to that lovely big boring machine I posted?
[22:55:07] <jymm> SWPadnos: There's another video where they outline the flaws in the system if you're interested.
[22:55:15] <SWPadnos> that one also runs LabView
[22:55:29] <andypugh> I like Labview, it's fun.
[22:55:45] <andypugh> I did a reallybig project in Labview Realtime
[22:56:04] <SWPadnos> that's a contradiction in terms
[22:56:11] <SWPadnos> unless you need really slow realtime
[22:56:18] <andypugh> No, it runs on special (expensive) hardware
[22:56:29] <SWPadnos> I know, I've used it, and it sucked
[22:56:29] <jymm> Please don't get SWPadnos started on LabView
[22:56:37] <jymm> (too late)
[22:57:01] <SWPadnos> I'm done - I have a new interesting Sudoku book :)
[22:57:03] <andypugh> Yeah, the interface for getting the program on the hardware was flaky at best
[22:57:21] <jymm> SWPadnos: Would you like a free version for xp ?
[22:57:27] <SWPadnos> the performance sucked as well, using the 3MGate FPGA compactRio iwth embedded RT PC
[22:57:36] <SWPadnos> jymm, free version of what?
[22:57:54] <jymm> SWPadnos: Oh I don't mind you ranting about LabView, I just know it's a thorn in your side is all.
[22:58:00] <jymm> SWPadnos: suduko
[22:58:59] <SWPadnos> oh, I have a good printed book, which I prefer
[22:59:12] <dmess> hi all
[22:59:13] <SWPadnos> and the version that comes with Ubuntu is quite playable too
[22:59:30] <jymm> SWPadnos: np, it's free and portable as well.
[22:59:47] <SWPadnos> well, if I ever make up a straight XP machine, I'll ask about it ;)
[23:00:04] <jymm> =)
[23:00:08] <MattyMatt> my java solver is quite nice, but it doesn't set new puzzles3
[23:00:48] <SWPadnos> try "Greater than Sudoku". "Product Sudoku", or "Killer Sudoku"
[23:01:07] <SWPadnos> there are no numbers to start, just some relationships or things like cross sums
[23:01:08] <MattyMatt> that's what my next solver is for :)
[23:01:11] <SWPadnos> heh
[23:01:30] <SWPadnos> oh, and worms sudoku
[23:02:11] <andypugh> Yeah, I agree that we ran out of CPU pretty quickly on that Labview RT system. It was still fun though. A rather big project just for a test rig for a propellere de-icer
[23:02:34] <SWPadnos> we were trying to get a 1 kHz loop rate on a power supply
[23:02:38] <MattyMatt> was it pre GPU?
[23:02:39] <SWPadnos> it failed miserably
[23:02:58] <SWPadnos> oh wait, 10 kHz was the original goal, we never got any more than 10-100 hZ
[23:03:06] <MattyMatt> i think I saw a gpu-accel labview
[23:03:11] <andypugh> We did better than that, I think, 33k6 serial comms
[23:03:12] <SWPadnos> not on embedded hardware
[23:03:17] <andypugh> Or perhaps 28k
[23:03:45] <SWPadnos> this is the book I got: http://www.amazon.com/Naked-Sudoku-Philip-Riley/dp/1402765061
[23:06:59] <MattyMatt> that's where carol vorderman went wrong. no stockings
[23:07:15] <andypugh> That's what you think
[23:07:36] <MattyMatt> what, does she get em out in her book?