theorb is now known as theorbtwo
[00:08:16] <L84Supper> http://cgi.ebay.com/PARKER-DAEDAL-LINEAR-BALL-SCREW-40200XXRMSD2H3L3C2-/350323264547?pt=LH_DefaultDomain_0
just add servo chuck and table
Valen: It isn't the wages that are the cost on that thread. I reckon it is going to tie the machine up for two days.
i doubt a machine of that size is really getting bunches and bunches of work
I wonder why 2" pitch? 4 TPI could be cut in a single pass, and would work just as wel.
could always ask what it was for
And it's not such a big machine, where my dad used to work they could cut 20' gears.
its not smal
Hang on, I misremebered, 14m gears, that's 45'
(yes, that is feet, not inches)
and it was running 24/7 making hundreds of them right?
at the full size
No, it was running 24/7 making half a dozen a year.
I exaggerate, probably running 8/5 in reality.
Nice machines though: http://www.davidbrown.com/products/girth%20gear%20cutting%20large.jpg
whats the gear for?
[00:32:07] <andypugh> http://www.davidbrown.com/girth-gears.php
They go round the outside of ball mills and cement kilns.
dont get your finger stuck in em
Nice promo video if you like heavy engineering: http://www.davidbrown.com/videos/engineers-are-born-not-made-video.php
Nice pictures Andy ... I visited a shop in Kentucky one time that was cutting really large gears like that for ships. They were very large. The company was located in northern Kentucky. I have no idea why they were in Northern Kentucky, so far from the coast. It took a long time to cut some of those big gears.
hm, 16in./sec rapid, fun
how is it calculated how much torque/force a belt(system) can transfer?
interesting calculator, maybe i can figure things out with those numbers if we have any info on the belts, i'll see, wondering how large a motor it can take before it just rips past the max tension we can reach :)
morific: it's the moments that'll destroy it
the cyclic tension
they probably rate them based on experience vs any hard formula
the cyclic variation
i just look at what doubling spindle motor torque does to amount of belts needed to transfer this, i am thinking twice would do, but i don't know what "spare" the current amount of belt system has
[04:12:27] <morfic> http://www.gizmology.net/pulleysbelts.htm
found this, looks interesting
did you find a belt maker with actual specs on the belts?
i don't wanna get too far w/o seeing the belts at work tomorrow
ok, now i have a calculator, but to fill it in, i'd be guessing from here on out
the trick for a consumer product is to spec a belt that lasts just passed the warranty period
pulley diameters, it's all at work :)
oh, you are the ARM guy, aren't you?
the whole labeling people thing helps remember who is who
whew.... I'm glad doody head didn't stick :)
it was taken, so something else had to do
did a bulls eye pop up on someone to pester for EMC/ARM? :D
there are ARM tablets with PCIe with touchscreen 7"-12" LCD's that could make for nice controllers
what's the PCIe for?
well for EMC2 they would be for stepper and servo controllers
in a netbook or tablet they could be used for wifi, bluetooth or wimax modules
there are other ways of accomplishing it w/o PCIe
which "it" ?
any of them
wifi can go on SPI, BT can go on UART, WiMax can be on USB... stepper/servos can be done through other interfaces
but the ARM soc's have PCIe
PCIe on ARM isn't that common
and the commodity modules for netbooks and tablets use PCIe
the phone/pda ones don't
on the new ARM soc's >1GHz (1-4 cores) with GPU's they have been adding PCIe
not all of them
anyways... be nice to be able to use general ARMs is all I am saying
TI , Samsung, Qualcomm and Freescale haevn't been, but Marvell has been
we should be able to support the mesa PCIe board without too much work
Hi, I am an absolute newbe on EMC and currently finishing my first CNC mill. I will read the manuals this weekend, but for final adaptopns on my mill it would be helpful to know what works easiest.
If one could explain to me if this actually works?
My mill has 3 axes, I want to set the home position in upper-left-rear corner of the cumical workiung space. At that points I have end switches available.
After homing, the mill shall set the X/Y origin to the front-left corner (means, that I correct the Y-Axis by a fixed offset.
Is this possible? I want to have 0/0 in front-left corner as this is identical to my CAD origin then.
[05:00:31] <awallin> http://www.linuxcnc.org/docs/devel/html/config_ini_homing.html
What I currently do not understand is how to do the next steps in adjusting the coordinates to my workpiece. I will use holders which are fixated on the machine's table. On this holder I will have a origin mark the whole milling program references to. I think about using a very fine tip instead of a cutter, manually jog to this point (X/Y/Z) after homing of the machine has finished, and tell the machine this point as origin of the work. Is this the
like em that much?
Can somebody, please explain to me? Thak you.
G54 work offsets I guess
[05:09:11] <awallin> http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl?CoordinateSystems
Looks good. Where does a mill usually have the machine's Zero? I'd prefer it in front left corner, but should the Z coordinate (vertical) be on level of the machines desk? For that, the tool would have to be sensed first, then I can set the Z-Axis to zero.
I would keep the coordinate system right handed
What do you mean?
on a usual mill that would mean front left bottom corner is the most negative
and top right back corner is the most positive
where you put (0,0,0) is then a matter of taste I guess
That's similar to my opinion So you place the zero point into the middle and use negative and positive coordinates?
I really feel a bit lost for now...
[05:16:49] <awallin> http://www.westone.wa.gov.au/toolbox8/furniture/toolbox/shared/resources_mw/techniques/images/ccs2.gif
This is what I plan to have, and I want to have the machine's (0,0,0) in left-front-bottom corner. But the home switches only trigger at left-read-top.
right, so then your reference position has X=0, but Y=yref and Z=zref
you can choose the numbers you want for yref and zref
that would be HOME_OFFSET in the ini, I think
I think about the following procedure: first I home to the limit switches, then I calculate an offset for Y and re-set this way my X,Y to front-left. With "Z" I don't really know what to do.
homing the machine is one thing, setting the coordinate system for a part is another thing, don't mix these two
Hmm. The machine must know its physical limits, on top of that I put my user coordinates, and inside of these I define the workpiece's origin. Right?
Or are the workpiece's coordinates directly defined inside the machines limits?
I would only think about two systems, machine and part
z is a bit special because there are tool length offsets...
You see, I am a newbe.
well I am not an authority on this :)
But still tousand times mor eexperienced than me.
canon goodies released today... (60D, L-glass, etc)
Can I deposit a sequence to be run at manual tool-change? I cant to lift "Z" to maximum height, then to Y=0 (the workpiece moves to the rear), so I have free access to the spindle. After tool-change, the mill shall move to a predefined coordinate (actually 0/0/0) and then slowly move worn the tool until it touches a sensor, then it shall update the tooltip offset for "Z" and proceed with milling.
try making a custom M-code that does the probing, and sets the tool-length-offset. Then in CAM you program this M-code after each toolchange
Ok, so this is not unusual. Fine.
if you are doing serious machining you probably want something that covers your sensor ?
with a lot of chips and coolant flying around...
pingufan: machine and job cortinates are really unrelated
you only use machine coords for stuff like tool changes
Well, I primarily want to do very fine milling (milling plastic enclosures, etc.). I have no coolant, this would make my workroom too dirty. But you are right, the sensor could get dirty by chips and give wrong results if one chip is in between tool and sensor.
As I have two pins free, I could control a solenoid which wipes a little brush over the tool-sensor to remove chips.
we are making a tool length probe http://www.cnczone.com/forums/showthread.php?t=109146
what toolholders are you using?
the typical MT3 on manual mills is not that great, all the tapers made for cnc are more precise
I will buy a replacement part from Proxxon, only the rotating axle, from a hand tool. This has the right cone and thread for a 3.2mm collet. I have to build it by myself because my mill is a former engraving machine I adapt by myself.
This spindle has an outside diameter of 8mm.
You see, a small mill. :)
And I have no reliable dead stop to ensure that the tool-tip is always in same offset.
Therefore I have to re-probe the offset as precisely as possible after every tool change.
[05:47:06] <awallin> http://www.youtube.com/watch?v=UtbHt-uO5IM
is that really good for the precise metal bit that says Mitutoyo on it ? :)
That's perfect. But I will directly put the sensor onto the machine desk.
Ok, I must hurro to my son's appartement. From there I will go online again.
awallin, I hope thats a worn workshop grade block he is using
it's worn now...
well the block could be carbide and the endmill carbon
then he has a blunt cutter :)
thats one of the things I dont like about physical touch off
any good DIY optical hacks out there? for tool-length
are looking for a way to measure a really small distance?
if so you might want to look into air gauging
air gauging will probably have trouble at a cutting edge
and dirt will effect optical, but is the most promising I think
Back to the sensor you showed me in a video-clip: How does this sensor work?
archivist, I wonder if you could use a sensor with a laser hitting it
use a lense to make a very small beam
and just use the beam interuption
pingufan_ is now known as pingufan
alex_chally, beam diameter is a problem for some tooling
I assume that a mechanical swich will not be very precisely?
archivist, what kind of precision do you need?
else you can buy now off the shelf from mitutoyo
are we talking .0001"
tool shape is the problem for me
archivist: did you see our probe?
form cutter for a watch gear
sorry, tool length probe
archivist, and what kind of tolerance in the measurements
I need to know the center line of the cutter
and the run out
cycloidal, and getting brakfast....
one day I will write up the problems I see so far
archivist, i think I have a plan for you
tram your mill very very well
tool has to rotate to be measured
archivist, to measure the center line?
so far I think telecentric lens, camera and backlight
archivist, if you can measure the centerline with the cutter stationary I have an idea...
you cannot easily measure the cutters,
archivist, if you have a surface plate, can you not just put the cutter down on the surface plate and then two ground pins of a diameter slight less then 1/2 the width of the cutter on either side, then measure across the pins, it seems to me you could math out the center line
ey cradek, thaught for your pocketpc ssh thing, is there a "tab" button?
archivist, as you know what the curve is that you are pushed up against with the pins, and you can mic over the pins to figure out their height
alex_chally, the teeth are tiny, .2 module has very small dimensions
it was a good idea too :/
one needs to remove machine mounting errors too, which means measuring after mounting
what makes it a harder problem is the cutters may have curve error and you need the center line at the width of the cut of one tooth of the OD on the finished gear
current method is set center of cutter tip to center of work, make, then fiddle make another till looks right, rinse repeat just for a one off job
good morning from germany
definetely nvidia drivers from apt make emc+axis realtime delay error.
mk0: yo da steckt was drimnn
i'm from belarus ;)
os 10.04 linuxcnc
is there a offical rti out or did you used hhe patched one
i only see http://www.linuxcnc.org/content/view/2/4/lang,en/
8.04 offical on the wiki its nonoffical
Experimental packages for Ubuntu 10.04
[08:36:48] <IchGuckLive> http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl?EmcKnowledgeBase
mk0 check the latency with glxgears
Valen: good idee
I found the nvidia drivers with SMP are fine, there is just a spike when you start an opengl window
dunno my home PC works good with nvidia. maybe smth with hardware.
what is it?
IchGuckLive, there is 10.04 too
i used the binary drivers in 8.04 and it seemed to work fine
axis ran really well with large toolpaths to boot ;->
glxgears says 5000-6300 frames in 5 sec. is it any good or bad?
if not using axis, i have no error
axis just tells you about errors
start latency test
well, 5000-6300 frames in 5 sec is good or bad?
i made latency test several times
thats well enoph for emc2
I'm getting 43802 frames in 5.0 seconds on my desktop
i'm saying start latency test, then look at the max latencies, then start glxgears while its running
I saw a spike of ~30K
however i then reset the latency test and continued at ~2K
max jitter 75453
yes this wars also the case for me this spikes sometimes acour igo tnormaly 4500 latency but sometimes 40K
Jymmm: still up?
what numbers are acouring to jitter
from 7000 to 70000
ignore the 70000
reset the value
it might be that bad lol
then start some more apps
mk0: is this a homemade cnc or a industrial one
i can change in ini file base period, that makes no delay error but causes following error )
homemade of course. but this PC runs soft for servicing electron microscope
what a good range of max jitters for emc ?
found it thanks
if you are doing software step generation you want the jitter low
i have it at 50,000(base)
and i have steppers
awallin: I watch this video on youtube (http://www.youtube.com/watch?v=UtbHt-uO5IM)
but I do not get behind, why probing is done in two different ways.
mk0: what's the cpmputer's specs, out of curiosity
i do not remember which vcard, it's 3ghz intel
mk0: did you look into the SMI fix stuff on the latency test page? power savings does the ugly it seems, can be disabled to help, check if it applies to you?
pingufan: part probe and tool probe it looks like, in probing you use the part probe to set x, y, z for g54, tool probe to set tool length
My problem is that I want to probe tool length with a precision of ~ 0.05 mm or better, but it must be compact and not expensive.
I repeatedly find back to touching a metal plate with +5V with the tool tip. When I touch it, it is grounded and this can be sensed.
This has no tolerances at all. Btw.: tool diameter is not bigger than 3-4 mm
I am only a little bit unsure if electric contact from machine's chassis over sliding rails and ball bearings will still give good enough conductance.
pingufan: in the first probing-move the z-height of the part surface is measured
in the second, the tool length
Ah! so you reference to the part's surface. Now I understand.
awallin_: What do you think about my idea with the metal plate?? Wireing is: +5V go through a resistor and optocoupler to a metal plate which is mounted isolated in known distance on the mill's desk. When the tool touches this plate, the optocopler is ON, without any tolance.
pingufan: what kind of optocoupler is this? sensitive to touch?
alex_joni:(you around?) couldn't find anything about closing msg with [x] (did you?), now i can't use the [x] without restarting emc ?
piasdom: I can't find it either, but I can swear there was a related fix
maybe it was in master, not v2.4, maybe jepler knows..
alex_joni: cool ...Thank what's master ?
main development branch, will get to be released as 2.5.x eventually
Fox_M|afk is now known as Fox_Muldr
any new progression on emc's robot kinematic stuff ?
Colinb: what kind of robot would you want to control?
Fanuc 420iw that i have sitting in my workshop
[13:20:06] <Colinb> http://sphotos.ak.fbcdn.net/hphotos-ak-snc4/hs267.snc4/39664_478947184516_650464516_6635385_4267009_n.jpg
that should be possible with emc2 as is ? or?
i think the kinematics need perfecting a bit more
i know alex_joni was working on it a while ago
ctrl-home does't home all axis, my computer ? i did it earilier and i pressed the combo 4or5 time and emc froze, had to retstart ... tried combo once and nothing
homing each separately worked
Jymmm: managed to fix it in the mean time
alex_joni: fix what?
OE error (dbx corruption)
thought maybe you know/have a prog. for that
I might have, but haven't touched it in at least 4 years
dump to FF format, clean the record, import back
Colinb: love the Fanuc! I used to play with Yaskawa Motoman. Great machines.
elmo i got it over the ABB, as the fanuc motors are easier to work with
the ABB motors only have resolvers and no hall sensors or encoder
hi elmo40 you asked me something the other day but I was out of the shop and now I can't remember what it was :/
your website with the recipes. it is a generated script (the format) or did you write it all by hand?
the recipe database is php and mysql
the other recipes with the fancy backgounds are done by hand
I wish enco had hss drill mills - I don't need carbide and I sure don't need to spend $20-30 each for them
try here http://www.lakeshorecarbide.com/14drillmills.aspx
$12 for a carbide 1/4" one
that's better, thanks
it's where I get all my non-indexable tooling
I like enco's free shipping but this would be worth it if I was buying a lot.
they ship via USPS too which is more cost effective but takes a bit longer
JT-Work: I guess that depnds on the destination
I have shipped Priority Mail from Calif to NY and arrived the NEXT DAY
you use all carbide?
I don't think I have the spindle speed to make the extra cost worthwhile
they just last longer for me even with a pos BP series 1 mill
anyone know where to find 1 meg X 9 70ns SIMM, DRAM
Jymmm was looking for them not long ago - there are a ton on ebay
cradek: I'm just surprised that enco doens't have hss drills
not drills - drill mills
[15:01:21] <cradek> http://www.use-enco.com/CGI/INPDFF?PMPAGE=163&PARTPG=INLMK32
drill mill == rotozip ? ;)
Any suggesting on flexible duct that can withstand a vacuum?
there are a bazillion up there
and the have the right one too
you have to pick it out based on your requirements
that's why I asked for a suggestion =)
in the search ox type duct
how do you think I knew there were a bazillion up there =)
I think I found what might work... http://www.homedepot.com/h_d1/N-5yc1vZ1xgl/R-100140592/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053
Actually I didn't guess, I searched =)
The laser has a 4" duct as does the DC. I think that 6" duct from crap depot should work nicely
JT-Work: I'm not fond of mail order, especially on consumables.
Hi all over the world
do I count in Swamp East Missouri?
Jymmm: I found my memory sticks for $5 each
heh, what were you looking for?
JT-Work>anyone know where to find 1 meg X 9 70ns SIMM, DRAM
ah. for what?
my Anilam CNC control
it has an 80386 motherboard
Kinda messy, but cool... http://mlyon.com/2007/01/computer-controlled-airbrush-gizmo-complete/
80386 does only take 265MB memory
I need to find a little air solenoid
maybe I can use a garden sprinkler one
the max memory on 386 motherboards is probably more like 16MB (four 4MB simms)
1 meg X 9 70ns SIMM, DRAM
Can upgrade to 64 meg memory Max.
i got aslot of these stuff here also still runing 25Mhz boards in full working mode on turninggrinding mashines
[16:55:54] <JT-Work> http://imagebin.ca/view/0UcpR9.html
JT-Work: so it has two 1MB simms now? are you trying to add memory or replace defective?
so it will give you max 512MB
JT-Work: DUDE, get with the times and toss in a Pentium! lol
cradek: add more memory
I have never seen a simm > 4MB. are they currently available?
cradek: 8MB is the biggest I've seen, maybe 16MB
256KB, 1MB, 4MB are the only ones I recall
but nobody could afford them =)
JT-Work: is it 386SX or 386DX?
dunno I got 1 meg ones
Damn JT-Work, after all these years, I had crap laods and just now do we BOTH need ancient ram
it only says 80386 when it boots up no mention of 80387
I mean printed on the cpu what does it say
ther is a number on the board
I don't really need it but I can edit a larger program at the machine with more memory
JT-Work: how many used slots are there, and is it all ISA ?
anyone know what the price of copper is, say compared to aluminium ?
Jymmm: look at the pic
l see an i387 chip in the photo
thinking about machining some heatsinks...
I'm looking, I can't see whats covered
can't open it up it is flinging chips atm
awallin: if you can get away with using aluminum it's a LOT easier to cut
JT-Work: I know you're only looking for simms, but would you be interested in a 486?
awallin: or brass?
hm, what is the thermal conductance of brass?
and what are the problems with cutting copper?
Jymmm: no the 386 does fine and if it shoots craps then it becomes EMC2 powered :)
awallin: Less than diamond =)
awallin: copper is like cutting glue - it's quite a nightmare
JT-Work: I have a 486 with the ram you need (I believe), but I dont' want to sepeerate them for obvious reasons.
when we looked the other day, those simms were dirt cheap on ebay
the drives are 10v +- analog drives with encoder feedback so the conversion should be easier than the first when the time comes
copper 400, alu 250, brass 109 in W/mK
yep I see similar numbers on http://www.engineeringtoolbox.com/thermal-conductivity-metals-d_858.html
cradek: not now
nothing is even close to copper
well gold is close
Oh great, be leary of J&J products.... http://money.cnn.com/2010/08/26/news/companies/johnson_depuy_hipsystem_recall/index.htm?source=cnn_bin&hpt=Sbin
silver is better than copper and gold both! I had no idea
well they make a whole lot of waterblocks for cpus and gpus.... so it must be cnc'able with some tricks ?
it can definitely be cut - just very very slowly
wonder if there's some alloy that is easier - I'm no expert
Cehck graphite, should be one step away from diamond
as a thermal conductor
copper is hard use a rouphing tool for it sharp as a raser
yes with lots of coolant, very low surface speed
maybe the heatsink should be prototyped in aluminium then...
I guess with cnc it doesn't matter - just let it run overnight...
Jymmm: umm, where do I get graphite, and how do I cut it, and is it going to be watertight?
awallin: you never used a pencil before?
heatsink -> waterblock
how expensive do you want this heatsink to be?
if the prototype can be tested cheaply then it doesnt matter if the final one is 500eur
it's for keeping a microscope objective at constant temp. the objective is 8k...
there are chermets 2x2inch very cheeap
they cool to -15DegreeCent
[17:14:53] <awallin> http://www.generalmanual.com/img/0706/200P2211A57.jpg
awallin: Notice they offer custom machining
what's the thing they are trying to cool? How many watts and what should the temp be at the surface and what's the ambient of the environment?
ambient is +20 to +25C and we want it at an adjustable +25 to +37 C. we have a waterbath with a pump that does the temp control
awallin: what is generating heat at the objective?
Jymmm: that's not too expensive, haven't worked with graphite before...
L84Supper: we just want it at an elevated constant temp
awallin: for $40, mightbe nice to play with
we have about 4 different lasers going through there, but they don't heat much
awallin: so you just need to heat the objective lens itself or the lens and the area that it is in?
awallin: "All grades of graphite and carbon-graphite sold through the GraphiteStore.com can be machined into various shapes using conventional machining techniques and tools. It is, however, recommended that carbide tools be used for better performance. For a large volume machining an efficient dust collection system is required. Please read the material safety data sheet for more details."
there are lots of small heaters in every imaginable shape as well
it's an immersion objective, so it's in direct contact with our sample, what we really want ofcourse is the sample to be at a stable constant temp
yes, some people use resistive elements with PID control and a PT1000 somewhere to read out the temp
but the waterbat is pretty simple and can be routed to many places in the experiment
You are so close to ambient you might consider a Peltier device so it can be reversed if need be
Jymmm: why don't they make cpu/gpu waterblocks out of graphite, if it is easier to machine than copper and better?
ok, I'd have to see the area. People not you in particular tend to just focus on the immediate area and forget about the whole system they are trying to manage thermally
awallin: it's brittle
awallin: would chip or crack
Brittle and porous
Pitch–based carbon fiber is a light weight, strong, self-lubricating material with excellent thermal and corrosion resistant properties, making it a good candidate for low friction, sealing and insulating applications.
aluminum and copper are readily available and easy to work with in China
They say SEALING, so I don't know
here's the Berkeley group solution: http://alice.berkeley.edu/content/pubs/Temperaturecontrolmethods.pdf
p4 has a sketch
awallin: that looks really simple, inexpensive and reliable
what's the O.D. of the objective?
and here are some germans using resistive heating and a PID-loop: http://www.opticsinfobase.org/oe/abstract.cfm?URI=oe-17-19-17190
L84Supper: about 32mm I think
awallin: HOLY SHIT graphite beats diamond by double http://physics.info/conduction/
in dem satz sind mehr fremd wörter drinn als in der schule hatte B)
the fluid system allows you to move the temp above and below ambient, where the heater just above or equal to
yes, good point. I don't think they make flexible peltiers that would wrap around the objective?
water heatcontrol is the best !
gotta run, thanks all for the brainstorming, back later
they make thermoplastics for injection molding that conduct heat better than aluminum but it's pricey and uses graphite
just press out parts, no machining involved
[17:32:48] <L84Supper> http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=4133298
I haven't seen any in production
Jymmm: I think there is something off there, there are two numbers for Graphite and one is much lower than Diamond.
I suspect the silly number is graphene or buckyballs or someting.
andypugh: I know it's used in brake linings. http://www.phy.mtu.edu/~jaszczak/graphprop.html
andypugh: ! do you think we could get those accupins divided out better than this? :) http://www.youtube.com/watch?v=FgOqEz5Tk-Y
It explains at the top, it beats diamond in bulk, but only parallel to the crystal layers.
skunkworks: Probably not, the difference is that you will know if you are or not ;-)
andypugh: diamond and grphite are VERY silular http://www.phy.mtu.edu/~jaszczak/structure.html
all you need to do is come up with graphene blocks with no imperfections :)
or take apart a bunch of pencils =)
Jymmm: Tell you what, I'll cut some glass with a diamond, you use graphite. Last to finish buys the beer.
andypugh: Finished! You done yet?
* Jymmm added 220VAC to the graphite =)
Seriously, bulk graphite does _not_ have great thermal conduction properties and is not worth considering for this application.
i got 240Vac outo f the plug
However, it is relatively easy to machine (if messy). I have used it to make formers for sintering ceramic springs.
ej by the WAY folks in the USA its 110 what is on the Plug at home actilly
They have pathetic, substandard electricity. :-)
* Jymmm connects the substandard 110vac to andypugh's testicals. go ahead punk, say it again! ;)
andypugh: I triple dawg dare you!
Is it on yet? I think the losses in the 3000 miles of cable are working in my favour.
so no real unswer to my Queset
Sorry, what was the question?
ej by the WAY folks in the USA its 110 what is on the Plug at home actilly
if you messure it
awallin: Um, OUCH! http://www.graphitestore.com/itemDetails.asp?item_id=3454&prd_id=483&cat_id=46&curPage=1
Jymmm: there is mutch cheeper one if you do not need the mass stabelity
I believe it is 110V RMS they get. But even here it is not a simple question. We are nominally 230V (actually 240V but "standardised" to 230 RMS. Rectified is 325V DC. 3-phase is 440V phase-to-phase but that is really 600+V rail-to-rail.
Jymmm: go to the next Tolmaker that hase EDM and ask for rests of graphite
they might have some blocks to throw away
IchGuckLive: tell andypugh =)
andypugh: got it !
bulk graphite is polycrystaline, and feels warm to handle. It's not the right choice.
with heading wire
andypugh: maybe if you found the correct graphite
ok im off for today By
andypugh: It CAN be extruded for mass production too
But not with a defined crystal direction.
id run into a bad python for the linecount circel grid generator
andypugh: but will that dramatically change the thermal conduction?
And, actually, I am not sure you can extrude it. Does it have a liquid phase?
andypugh: powder to slury to paste to block
Yes, thermal conductivity (accordong to that chart) is 2000 in one direction and 6 in the other.
Bulk polycrystalline averages to about 160, which is nothing special.
andypugh: that's 1 of 5 videos for the episode
I do know quite a lot about materials science already, you know ;-)
andypugh: Hey, I learned all I know in 30m of watching that =)
I was thinking "that's not entirely true" within the first 10 seconds.
Chap saying "steel won't absorb that". I would like to see who wins in a head-on between his racing car and a battleship :-)
In respect to an air brush compressor without a tank. Is the CFM related any in respect to any reserve? Would I get more airflow by adding a storage tank?
smoother flow I would suspect, but what about more flow at less pressure?
I thought they were inverse to each other
Once the tank is up to pressure it basically makes no difference to flow rate
[18:55:04] <Jymmm> http://www.harborfreight.com/1-8-eighth-hp-40-psi-oilless-airbrush-compressor-93657.html
With a big enough tank you can have any flow rate you want, but eventually the pressure will drop.
it's rated at 0.5 CFM
yeah, pressure is no biggy, it's just being used as a blower
Yes, I guessed that part...
you asked *shrug*
It is likely to be 0.5CFM at some very low pressure.
it's not connected to anything, literally just blowing air where the laser is cutting
(Well, I guess that goes without saying as the CFM is free air volume)
I suspect it is the wrong thing for the job.
A radial flow blower will probably work better.
Many use airbrush compressors for this
This is a laser engraver
Something like http://uk.rs-online.com/web/search/searchBrowseAction.html?method=getProduct&R=0250943
no no no I already have a dust colletor at 900 CFM
oh, heh no scale refernce there =)
I thought it was 16" tall =)
That's fairly small. It would need a duct.
What is the air meant to do?
andypugh: prevent flame ups
So, cooling mainly then?
not exactly, hard to explain
That little fan is 4 CFM (doing the conversion)
But won't push much down a 6mm tube, if that is what you need.
I have a coupel of those type fans here, I wonder if I could "duct" them
I'm thinking more like an 1/8" coiled tube
Ideally you would work out the air volume you need, then calculate the pressure drop through the delivery system, and work from there.
You are going to need some serious pressure to get any flow down a 4mm tube.
So that fan won't work (though if you mounted it on the laser head....)
thus the air brusher compressor =)
I don't know, I think it may cause harm to the optics
My fear is that they are a bit rubbish, and not really continuously rated.
I dont want to cause a vacuum near the optics at all
A higher CFM with a reservoir would be better.
Something like http://cgi.ebay.com/ICO-SAL-Italy-Small-compressor-Air-Brush-Arts-Crafts-/200512075812
Would be a lot better.
needs to be oilless
I wonder if I could use my vacuum pump, seems a waste to do so
That won't be oil-less
this one is
I see a lot similar to the one linked for dental use, which I assume have fairly tight oil-less-ness limits.
And I would have thought that anything for airbrush use similarly doesn't want oil in the paint.
But I don't know enough about the subject.
thanks I found some Medical compressors on there
bridgeport arrived moments ago..... hey this thing looks like it belongs on a battleship
L84Supper, oh you finally bought a machine?
bought a few
first i could not find any, then three in the same day
so I might have a Bridgeport or Cincinnati for sale after I have the CNC units built
YAY! No more ghetto laser stick!!!
I think I have a bad router :/
Fox_Muldr is now known as Fox_M|afk