* JymmmEMC makes electrified iron leggings for bigjohnt's wandering problem
Big J's history lesson is accurate and acknowledged... ;)
learn ti file before you jump on a cnc... it'll be worthit
skunkworks: starting over on the layout?
[00:19:34] <skunkworks> http://imagebin.ca/view/RBqYRa.html
a bit. I need to make it a little tighter.
I love the way jmk make the power-handling traces
(This has the driver gnd hooked to the mosfets.
I still am not sure about that.. Like what happens if the voltage across the resistor goes negative.
POOF is my buest guess....
Hey, This is not really a CNC machine question but has anyone used an automatic boring / facing head?
[02:44:07] <SWPadnos> http://www.theonion.com/content/video/in_the_know_should_the_government?utm_source=videomrss_89550
J F yes numourous times... whats your question??
how to use one
automatic can be mechanical OR electronic??
program a u or w axis... what machine?
This one is mechanical.
so what axis is the quill that it hooks up to
enco are usually small stuff.... how big?
It is boring head but if you hold the top while it is spinning the tool moves outward
For a vertical milling machine
maybe 3 to 4 " dia
manual boring and facing head... needs a stop rod
i see... sweet did you get it cheap??
so the stop rod extends from the part that you keep from spinning with the spindle?
yes I acquired it
I don't see a place to insert the stop rod
slick... acquire 1 for me.... LOL
but the top part is knurrled(sp?)
you can make it move at three different rates per rev
there should be a tapped hole on the upper part of the head to take a stickout rod??
what is needed in a machine for rigid tapping?
a spindle encoder
the spindle has to become an axis
i wonder how i do that lol
dont hmmm me
ive heard it too many times NOT to use it :)
it seems so useful though
for rigid tapping, you need a reasonable resolution encoder with index on the spindle, and you need to be able to control the spindle direction (and ideally speed)
pulse encoder SHOULD work... i haven't gotten mine going yet..
not for rigid tapping
if you're talking about 1-PPR (index only) feedback
no.. rigid.. is servo/spindle control
did the encoders that are exact count, are they workin with emc yet?
dmess, no, you don't need servo control of the spindle, just good feedback and a Z servo that can handle the acceleration demands
i havent wired them yet..
Gamma-x, are you referring to absolute encoders?
then no, there's no specific support for them yet
it may be possible to write code that would fake it, but it's not written yet
i believe toshiba only needed a z-axis encoder
not worth it to me. id rather have a reliable machine
how about the spindle break.
if i have a vfd is it worth it to buy a spindle break.. like a breaking resistor
it's best to not break your spindle :)
but braking is OK :)
braking* haha sorry
i have a brake AND a vfd
dmess, u like it?
they're meant for different things
a VFD braking resistor can only slow the spindle down faster, it's a load dump
it isnt running yet... i cant finger out the config
it doesn't prevent it from moving like a physical brake does
i thought it stopped the motor
and a physical brake isn't usually used to stop the motor, AFAIK
it's not like they have replaceable brake pads or anything
i think it has a brake
i have a $750 brake in a box
an air break. i just need to configure that actuator into emc
what's more useful is a Z axis brake, so when you E-Stop, it stops the quill/knee (or whatever) from falling
there's a brake signal, and if you compile TRUNK, there are other signals that can be used to control when the spindle moves after a speed change or the like
and SLAMM into the bottom end of the scre and get STUCK
err, to control when EMC starts motion again, after a spindle speed change
SWPadnos, u reffering to a limit switch on the z axis?
or worse, slam into someone's arm after they hit E-Stop
no, a brake
sorry kidna confused on the z axis brake.
if you have a counterbalanced quill (which you likely do on your bridgeport/clone), then it's not all that important
i had my knees taken out by a Hermle splash pln
ended up with a 4x4x6 inch block of jackpine as a bumper stop
stop drop and roll when it happened
SWPadnos, i have a supermax...
right - close to a Bridgeport
a YTM-5 or something
wich is pretty much the same as a ycm-40 with older control...
you should only need an encoder of reasonable resolution and to tune the z drive to match it
well, at least I had the Y and M and the dash right :)
ive done 1"-8 x 8 dp... and pecked it out ;)
3 hp 3 phase on a vfd so about a 2hp motor.
wow mine is 0.5 hp
spindle brake. power draw bar, auto lube, coolant taper #40 ns i believe. 49 x 9 table
and at the time a working anilam with 27 pnd servos,
all for 2 grand
are you modeling this?
hey... i havent modeled my hardinge
you have HAL handling it all yet
my table jsut seems to run away lol
[03:19:11] <dmess> http://www.youtube.com/watch?v=j_zPXtaGTQs&feature=related
this will sooth your mind
[03:23:52] <Gamma-x> http://www.youtube.com/watch?v=Ddn4MGaS3N4
this tends to sooth my soul
keep it on a medium volume
wow - http://www.youtube.com/watch?v=e_P_-cFbGbU&feature=related
man, he's pretty darned good
I can do that <rolls eyes>
so can I, but it doesn't sound as good :)
I was looking for some good quality recording with Leo Kottke, and this is all I found that I like: http://www.youtube.com/watch?v=wQKbwLqKEOI
HAL9000 is now known as SkinnYPupp_
(well, I like a lot of the other songs he plays, but a lot of the videos are handheld balir witch quality)
a different take on "Stairway To Heaven": http://www.youtube.com/watch?v=HjXN3OLgoqs&feature=related
(one I like)
[04:01:21] <cradek> http://www.youtube.com/watch?v=P07Di283vfw
a different take on "music"
I thought it was hilarious
quite a contrast from Tommy Emmanual
I didn't look at any of the others yet - firefox upgrade running
man, I didn't realize that Jordan plays two guitars at once O_O
cradek, that is a "different" take on "music"
that guy is doing rythem and lead parts at once
jes hes def from another planet like jimi
[12:54:15] <fragalot> http://i4.photobucket.com/albums/y127/BrissyMonk/ChopperOne_RSide_Front_LG.gif
what is it?
update manager has the string busy so I can't go look
you need more than wet string BigJohnT
well we have tin cans at each end...
BigJohnT: it's a pretty awesome chopper PC case
get them gold plated
nice... and easy to blow the dust out
well time to go
archivist: while I don't doubt that "casemod" requires a lot of skill, I still can't manage to like it.
fragalot: ^^ er, that was directed to you
jepler: personal opinions. You are entitled to your own, but i admire the work put into it :)
the 'radiator' is neat, and possibly even useful
however one reason for a computer case is to keep the cats out, and this one seems to fail at that
cradek: you could just put plexi on the sides
screws that could be used for that are already in place
Just took the plunge and bought a Boxford AUD http://www.lathes.co.uk/boxford/page2.html
Lathe and Beaver Mill http://www.lathes.co.uk/beaver/page5.html
from Home Workshop Machinary.
does anyone have a vim syntax thing for gcode
also nice purchases, paragon
toastatwork: I've been meaning to upgrade my Granville for some years now but kept on putting it off I've never owned a manual mill so this is my first. It's just the right size for my workshop due to space constraints. Got some bad news today so thought sodit go for it :-)
heh so you about to get the level to fix the Granville and its retired
hmm Bridgeport seems cheap at the moment
[15:05:51] <archivist> http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWAX:IT&item=280284293224
I want a cnc one though so it already has servos etc
wow that looks like a well-used and then well-rotted machine
"I WILL TRY TO WIRE IT UP BEFORE LISTING ENDS. THERE IS NO REASON IT DOESNT WORK"
archivist: Yep the Granville is retiring. Though the level will come in handy for the new lathe :-)
what I should go for http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWAX:IT&item=290274520486
I've now got to go rip out the work top that I just built out of 2X4 to make room for them :-(
I have a question regarding inverters or 3 phase conversion. The mill has a 1hp 3ph drive motor a 3ph powered table and 3ph suds. The lathe has 3ph .075 hp and a small 3ph suds motor. I guess I need to buy two digital inverters but I saw mentioned that the suds and the power feed are small so a cap can be introduced to drive them from 240v single. Is this the best way to go and how do I...
...workout the size of capacitor for the motors?
ah well, adjust walls
Tried that ;-)
Capacitor depends on motor
Paragon: I did that recently with my lathe's coolant/oil motor. it is 1/6 HP and it took quite a bit (about 16 uF?) of motor run capacitors
I adjusted the capacitance until it seemed to start reliably (takes more capacitance) but the current in any of the three wires wasn't (much) over the motor rating
(it feels like a juggling act and is a fairly poor solution to the problem)
cradek: and you just happened to have a bunch of spare x00V capacitors in the uF range to test with?
Especially if I need to do it for 3 motors...
you people with overdeveloped junk boxes make me envious
yes, they're not expensive, the metal can type
might be useful TM
NB: motor RUN capacitors, not motor START capacitors
Is there a calculation for it or is it more a trial an error thing?
nobody has a vim file for gcode highlighting?
toastatwork: check the emc-users archives
where is that?
Paragon: google told me a rule of thumb, I forget what it was
[15:24:10] <cradek> http://news.gmane.org/gmane.linux.distributions.emc.user
cradek: No worries Ill search our best freind ...
Paragon: lots of jmkasunich helping me with it here: http://www.linuxcnc.org/irc/irc.freenode.net:6667/emcdevel/2008-10-15.txt
What do you think about using one inverter and have a switch to change between mill and lathe motor? I would only be using one machine at a time.
that does not sound like a problem
having one big enough to run both seems nice though
not with a VFD
one motor per VFD
Problem is that the digital inverters are designed to be used for one motor at a time. So I would need to switch the output of the inverter to what ever machine I wish to use
is that what you mean by inverter, a variable frequency drive?
that's not the only problem
SWPadnos: Yes it is
Is it torque tuning as well?
you also need to tune the VFD for the motor
oh I didn't understand you meant VFD
I thought you mean a phase converter
I thought that may have been the case.
there are two animals a vfd (which is an inverter anyway) and a fixed freq inverter
that's one advantage of a rotary phase converter :)
get a bigass 3 phase motor from a junk dealer - put a pulley on it and spin it with a cheapo 1 phase motor to start it
and two types of rotary
These things http://cgi.ebay.co.uk/NEW-1-2HP-240V-SINGLE-TO-3-PHASE-INVERTER-CONVERTER_W0QQitemZ400009336917QQcmdZViewItemQQptZUK_BOI_Industrial_Automation_Control_ET?hash=item400009336917&_trksid=p3286.c0.m14&_trkparms=72%3A1301|66%3A2|65%3A12|39%3A2|240%3A1318
no funny capacitors to deal with
* skunkworks has been lucky to always have 3 phase to play with.
Thats probable the cheapest way cradek is there any draw back from that method though?
this is more or less the one I built: http://www.metalwebnews.com/howto/phase-converter/phase-converter.html
Paragon: no, actually I think it's one of the best solutions
the "wild leg" often has a vastly different voltage on it unless you add run caps
(using cradek's approach, not the one I linked)
SWPadnos's is similar except he uses a cap to start it instead of another motor
a "real" rotary converter also has run caps, which keep the third leg voltage in line
you can pull start a 3 phase motor on single phase.... (just don't wrap yourself up in it) :)
heh, use cheap string :)
* skunkworks should shut up.
why get a 3-phase converter when you can get a vfd, though? http://web5.automationdirect.com/adc/Overview/Catalog/AC_Drives/GS1_(120_-z-_230_VAC_V-z-Hz_Control)
Only if you have no desire to control motor speed, I suppose.
that's true - a lawnmower starter would work great (and you wouldn't get hurt)
jepler: several machines with several motors each
cradek: ah, I missed that
Pull start really ... and it will run ok?
skunkworks: it would take some knack to get it going the right speed before kicking in the power
Paragon: a motor would be better :-)
Not the most elegant but interesting non the less
from what I rememeber - you don't have to get it up to speed - just get it moving
but it would depend on the load
when I had incorrect pulleys on mine (starting at a slightly wrong speed) it would sometimes trip the breaker - after I fixed that, it always starts
it's a very big motor though (8 HP?)
I just noticed I have 2 x 2200uf caps could these be used?
you need AC-rated motor run caps
you probably have electrolytics there, which would make a nice mushroom cloud
the rubber bung gets out with some force :)
[15:38:40] <cradek> http://surpluscenter.com/item.asp?UID=2008112009375811&item=22-1294
Yeajh I am not sure what they are they are big say 5 inches high by 2.5 inches in dia
this is what a motor run cap looks like
Oh Ok ... not to pricey either :-)
no - don't skimp and use something inappropriate - this is dangerous stuff.
pricey or not
paying to live is a nice deal.
one nice thing about a rotary phase converter is that once you get it going, it gets better as you turn more motors on
the total motor mass keeping the phases going the right direction goes up
SWPadnos: that's what she said.
when your mill spindle is running, everything else will work better
and the converter is really only used for starting
so you could put a pull-start on the mill spindle, and it would run the other motors.
so you can make a 5HP phase converter, and then go start 10 5HP motors
or if really rich use a motor driving an alternator
or if really really rich get 3-phase service
the motor:alternator thing is pretty hard actually. you don't get good intrinsic speed control with a 1-phase motor, and speed is importnat since it determines output voltage
for some UK houses thats just a trench and a meter
coffee time yay!
SWPadnos: that homemade inverter you linked to is that a rotary or static. Just that it mentions rotary but I was under the impression a rotary type used a motor. Also how much did it cost to build roughly?
a rotary phase converter is a static phase converter with an idler motor
depends on scrounging skillz
mine cost $150 or so, since I had to buy everything (no junk box at the time)
Thanks for this info Guys...
motor, enclosure, time delay relay, outlets, caps, bleed resistors, start/e-stop switches, contactor ...
I probably have a schematic of what I made somewhere. if I find it I'll stick it on the web somewhere
SWPadnos: $150 ???? What store did you rip off?
don't tell anyone
the enclosure was the most expensive part, I think that was $35
now, off to make the coffee, for real
you can't even buy a case of corn flakes for $35
I'm off to make space for my new toys ... CU all later and thanks again....!
Yeah, go make coffeee, wake up, and tell us the REAL cost
automation direct baby
skunkworks: But he said EVERYTHING for $150
hmm I have a motor from Ward Leonard speed control
funny. Like me and my co-worker. I round down - he rounds up.
my co-worker and I?
skunkworks: me is right: "Like me" + "Like my coworker" = "Like me and my coworker"
skunkworks: notice you would not say "Like I, ..."
"Like I and I's coworker"
well jepler might, but he'd sound off
cool - thanks
I thought it usually was the other person first... My coworker and I
today's lesson brought to you by R, W, and the number 3
ha ha ha, three endmills! ha ha ha
snuffleupagus is my hero
but HE'S INVISIBLE
what lesson does that teach our children!?
don't tell anyone
Ive noted a resent change on the BBC with respect to "and I" and "and me"
cradek: they can have an imagination to retreat to when the world tosses crap at them?
archivist: a lot of people were taught incorrectly that "and I" is always correct and "and me" is always wrong.
archivist: then they get confused and start using "myself" bogusly
same as speeeeling changes
"If you have questions, please talk to george or myself"
my favorite singer at the moment (feist) was on sesame street http://www.youtube.com/watch?v=9fciD_II7NI
which is "please talk to george" + "please talk to myself"...?
please talk to george or me is what I would say
I'm such a pedant. sorry everyone.
anonimasu: and you would be correct
Me, I'd say "ask george". I don't want to deal with those questions.
* archivist uses the Queens engrish not USAean
ok, I'm with jepler
our english teachers here teach a bit random of both..
I miss the muppet show
cradek: here, this will make you feel better: http://failblog.org/2008/11/17/sign-win/
(I don't know who started me reading failblog, but I want my time back!)
jepler: I love it
augh i couldn't get the vim highlight to work
but are thoose things really staples?
I blame someone in #apache for my time on lolcats
[16:06:13] <anonimasu> http://www.morgana.co.uk/assets/Staples.jpg
can you use single quotes?
heh, that is a funny pair of postings
but the one with correct emphasis should be stapled to the bulletin board :)
geez. there it is again: http://www.newegg.com/Product/Product.aspx?Item=N82E16820145184
4GB DDR2 for $25 including shipping, after rebate
huh, why do I feel tempted to buy that?
my machines have a perfectly adequate amount of RAM
because it's so inexpensive, of course
adequate, is that all you got?
you need LUDICROUS RAM!
it's true that my swap space is used
hm, but the machine in question takes DDR RAM, not DDR2
oh, that's a problem
I guess that must make it ooooollllld
I wonder if DDR is still available at non-usurious prices
I bought some earlier this year, but I forget the price
ok, not too bad. only ~2x the price of DDR2
2G = $25 after rebate
jepler: my problem with failblog is I don't like watching people get hurt. the rest of it is really funny though.
i've worked my taps up to 1500 rpm and 1000 rpm
i wonder if i can go faster
one way to find out,.. but,.. don't taps have (just like drills) a certain RPM you should run them at to get the best cuts?
cut taps, yes
form taps have much higher speeds
I think form taps can go higher
but it depends on the material
the 1500 rpm tap is now accel limited
the other one has room to go
the spindle only idles for a fraction of a second before reversing
* alex_joni would then be happy with 1500 rpm
the feed rate is just shy of 40 ipm, too
sounds fast enough :)
at least it makes a cool sound
do visitors duck when they hear it the first time?
no, it's quiet
then it's not fast enough
just the fast whirr of the spindle accel
Faster, faster, faster!
until the thrill of speed overcomes the fear of death.
break any taps getting it up to speed ?
then it's definately not fast enough :D
toastatwork: kidding ;)
now you need spindle power measurement to detect tap wear
archivist: that's not that complicated
impossible, the accel/decel is huge compared to the running power of the tap
yeah, but recording the profile
servo loop err :)
and comparing with the next one should be ok
even pid profile should be somehow conclusive
wait till it changes x %
i guess, it's a 10 hp spindle
the power when it's tapping doesn't even show up in the monitor
the accel drives it to 50%
you can gate the load checking with an "at-speed" comparison
so only check spindle load once it gets up to speed (then maybe latch that status, in case the spindle slows down at all)
(which it shouldn't if it's 10HP and you're tapping anything smaller than a couple of inches in diameter :) )
what i'm saying is the idle load is 1% or so
and it drifts up and down at least 1%
i think the error in the measurement is larger than the value i'd be looking for
could be - smallish taps?
10-32 and 4-40
oh, tiny compared to a 10HP spindle
even my 0.1HP can tap that ;)
(that's my hand, not my spindle)
it would be interesting to see if this has some method for logging tht
may need to add a torque sensor between spindle and tap in the holder as you have a brute driving the poor little tap
oh, that would totally work
torque sensing tap holder
log the peak value on the holder, and once the tap line is finished, look at it
I use to work for a company making the electronics for torquemeters
when the toolchange goes off, cuts power to the holder and thus resets it
* archivist checks their website, looks like my old code is still being used :)
technology that was used could easily be applied to a toolholder system, hmmm I wonder
i cannot find any open source thing to get cnc syntax highlighting
what are people using
I go without highlighting at the moment
[18:37:00] <archivist> http://osdir.com/ml/gnome.general/2004-06/msg00033.html
looks fixable in gedit
I just found where to play in /use/share/gedit-2/plugins...
I love how stuart has converstaions with himself on the email list. :)
trouble shooting at its best
when will emc have double closed loop?
* anonimasu sighs
I've got a pysics test tomorrow
I passed it once, but the grades sucked because I didnt have a formula collection ;)
the book with F=ma that you are allowed to keep on tests
material data and stuff
in other words.... "show your work" rap?
instead of just giving the answer, they want you to show your work
they grade on both the answer and the calculation
but even if you fail the correct answer you can get points on the calculation alone
if it's 50% right or so
If you can't dazzle them with brillance, baffle them with bullshit!
i really like those kind of tests
at school in the ME dept, all our tests are like, single question
they're really cool.
Yeah, like that's a REAL tst of what you've learned or not.
I mena, it doens't have to be a bitch if a test, but I had a friend that graduated HS and couldn't read. - kinda pisses me off.
these were not "gotcha" questions, either
He went to college to learn to read. He shouldn't of had to do that.
they were simple, real engineering questions
"how big does this need to be? see you in an hour."
and that is really sad re: reading
does emc have the ability to write script lettering ?
emc doesn't know how to write at all
emc is a machine control, not a cam system. your question only makes sense for a cam system
if you have a CAM program that can convert script fonts to G-code, then EMC can run that code and mill script lettering
hmmm. too bad this thing is so heavy: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=200274154049
piasdom, you're welcome
(other pages show that it's in the 13000 pound range)
yeah, they're real heavy
but if it goes in a garage, the rigging isn't THAT bad
they essentially move it into a spot and leave
yeah, I sure wouldn't want to move it up or down stairs
just get a couple of friends or twenty
it'll be fine
"ok guys, on three and down the stairs"
sweet macine :D
hat in hand - begging help :)
yes - again
did you see my email? I am just starting to draw it on my white board so I can understand the problem
* jymm tosses toastatwork down the stairs.... "Here CATCH!!!"
another position jump?
* skunkworks loves my 6'X4' white board
* jymm draws on skunkworks whiteboard using a red sharpie..
whiteboards can explain a lot
hmm, I was looking at your source again, hoping there was a simple way to compile it outside emc with the ability to just run numbers through it
there's so much hal stuff that I don't see an easy way to do that - would have to replace a lot of stuff.
wow, it's getting complicated, isn't it
this is doing the partial differentials one step at at time
you could compile it on sim and halscope some numbers
one thing that struck me as odd is that the s2r function uses both p and t in calculating z, which doesn't seem right for the polar coordinate systems I know
it seems to me that you'd have z=r*sin(p)
but that's y in the function
(actually, the order the ordinates are calculated leads me to believe that you did it "right" at first, but then swapped things around because something didn't work as you expected)
stustev, what pivot_length are you using?
hmmm. again, without simulating, writing, or looking at the machine, it seems strange that you have pivot_length accounted for twice in the KinematicsForward function
it's used in calculating r, then it's also added directly to pos->tran.z
stustev: as an aside, I notice that you have haldata->tool_length remnants - that's a holdover from a failed previous strategy I tried
looks unused - can be removed?
looks as if I need different forward and inverse functions for the Zcomp
have you tried setting various parameters (like pivot_length) to 0 to see which one(s) cause the jump?
while running in sim of course :)
I have not - I don't mind using the machine - the jumps are very minor (usually)
I get no jumps until I try to use a tool_length (G43)
I think the problem is the difference between the joint and pos-tran.z after the W tool length
do you get it whenever you have a nonzero W, or only when you have a tool length?
I will check - bbiam
(I bet you are right)
did g49 - g91 g28 z0 w0 - no jump
w-1.0 - jumps
stustev: got a link to the latest code?
g43 sets pivot_length?
g43 sets the tool_length - I have the machine configured to use the tool length along the W axis
g43 is a red herring
the problem is when W is nonzero
the machine jumps when W is zero after I set the g43 h08 and move the axes to Z0 W0
yeah, I mean the unoffset W axis. that covers it up because you have an offset on W
yeah, but in that case joints is not zero.. right?
well joints = pos->w which are both nonzero
how does pivot_length get set?
a parameter in my .hal file
so that's a nonzero constant?
I will put my latest config files in www.mpm1.com:8080/cinci - bbiam
somebody's gotta teach that guy about ssh ;)
SWPadnos: Ssh... it's a secret
a 8196 bit secret
that's the key
stustev: is it viable to remove certain compensations?
it'll probably move "wrongly" .. but you should be able to spot jumps
alex_joni: can remove any and/or all
SWPadnos: I don't have ssh on the machine - I guess I should put it on there - I use it on the network but not on the machine - I will put it on there
stustev: for some strange reason I suspect s2r, so I'd leave only that :)
yes, it does seem strange that you'd use sines and cosines the same way for both forward and inverse kins
hey, that's the part I wrote
... well originally
it seems to me that you'd need to do the (uh) forward kinematics (? - from joint space to cartesian space) sequentially
take the joint closest to the tool and calculate the impact of its rotation (and W length) on XYZ
then, using those results, you can apply a transform on the next joint out, which takes into account the values already calculated
it's certainly possible that all this would condense down into a single equation in closed form - I haven't thought it through that far :)
(either to get the equation or prove why it can't be done)
there is one pivot - from the center of A,B rotation down to the tool tip (gauge point actually). it's not a robot arm. the gauge point moves in a sphere around a point that's fixed on the Z slide. it's extremely simple kinematics
uh, "Z slide" = "joint 2 slide"
stuart is making it much less simple :-/
in his case, he has several pivot lengths that are all orthogonal - each one still gives you an offset from the center of rotation to a point on a circle or sphere found according to A,B - and I think you can just add them up to find the gauge endpoint
actually now that I come to that realization, I can see that's just what he's doing
well ... or not
I'm not sure what he's doing now
* alex_joni is off to bed
good luck spotting this :)
er, whoops that whole scrollback thingy
(for your x00V capacitor)
hello again - I will try to explain what I am doing
Maybe even a LIVe microwave.... some are really cheap - some cheaper than the individual componets you steal from it.
Xcomp is to adjust Y and Z for orthogonal errors along the X movement
Ycomp, Zcomp ditto
Acomp adjusts the X axis for the out of parallel condition of the X axis and the center line of rotation of the A axis
Bcomp ditto the Acomp - just for the Y axis
the whole point is to position the tool tip in the programmed location and pose the machine to cause that tool to be in that position
the comp functions describe the physical attributes of this individual machine
this allows this machine to position the tool tip
the tool tip must be in position and orientation
cradek: stuart isn't making it much less simple he is trying to make it much more robust :)
SWPadnos: ssh is now on the cinci - so there :)
ssshhhh - don't tell anyone :)
too bad I can't put ssh on my white board
has anyone put together some point cloud processing stuff, preferablly within EMC?
Hello Chaps.. Ive been looking at single to 3 ph coversion today and was wondering if someone could explain the consumption power of the idler in a rotary converter. I am awaiting delivery of a 3ph mill and Lathe. Lathe = .075hp + has suds pump 3ph. Mill = 1hp + suds + one powered table all are 3ph. I do not know the rating of the suds or table motor but they are quite small. Generaly only...
...one machine will be running at any one time. What size idler motor should I go for and how much power does the idler use when machines or not in use?
ps I know did I had a discussion running earlier but this is a follow up with regards to that discussion.... Thanks
at least 1.5hp but the bigger the better
the higher the rotary converter's rating, the more efficient it will be
fenn: Sorry I forgot to mention that the lathe motor comes with a digital inverter so it is only the mill motors and the suds motor on the lath.
oh, well, same answer then
Oh ok :-) What about the power usage of the idler when it is not running and equipment?
also you're not supposed to keep the converter running unless you're in the shop, using stuff
like an air compressor
i have no idea how much power an unloaded motor draws
spose it would be easy enough to find out though
i've heard of "sealed rotary converters" that are filled with hydrogen for heat dissipation and lower internal air resistance
Wow hydrogen that sounds explosivly dangerous!
nah that's a popular myth
unless you are in a submarine or something
the idler takes <5% of its rated HP
fenn: Guess you need oxygen to make hydrogen dangerous. SWPadnos is that when its supplying running equipment or when just idling with no equipment running?
idling I think. it shouldn't really use much anyway - it's not driving a load
SWPadnos: Thanks for that.
I've had mine running for hours at a time, and can barely feel any temperature difference after that amount of time
I was concerned about the same thing ;)
Yes I read like 2.2 kw for a 3hp motor (from memory) and was concerned that it's was like having an electric fire running constantly eating up electricity ....
Glad thats not the case :-)
though it might be useful in my unheated garage
I have been looking at this site also with regards to circuits for 3ph conversion http://home.att.net/~waterfront-woods/Articles/phaseconverter.htm
yep. I think I saw that page when doing research for mine
one thing to note is that if you go the VFD/static converter (or pull-start) approach, you have to derate every motor by 1/3
if you build a rotary converter, you only derate the idler motor (so you'd use a 5HP motor to start 3HP loads ...)
that's not even strictly required, but it's a good rule of thumb
yes... but it is noisy
Due to receiving about 80% efficiency?
what is noisy?
it's worse than a desk fan bur far better than any tool
the ones ive seen have been another motor running making noise..
well, mine has an idler motor, but it's pretty quiet
the exhaust fan on my water heater is far noisier
then very well done... make me a 1/2 hp one so i can run my hardinge??
1/2HP - that's nothing
get a bigger motor and maybe we'll talk :)
its all it needs
but its a baby machine..
all it needs is love
the spindle doesnt move my .0001" indicator
I more or less used the circuit here: http://www.metalwebnews.com/howto/phase-converter/phase-converter.html
I changed a few things since I didn't need the remote switches, but I wanted a contactor and overloads inside
im not the strongest electonicly... im a mechanic at heart
so mine has an e-stop switch, a start button, and an "overload tripped" indicator
plus a few NEMA outlets (and one hard-wired feed to the bridgeport)
(little extras: the start button lights up when you release E-Stop, the E-Stop button lights up when the thing is running)
SWPadnos: I was looking at that circuit earlier today when you sent to me. How does the overload work?
well, on mine I have a contactor that drives the idler (and therefore also the other loads)
it's never tripped, so I don't know for sure that it's doing any good :)
oh, I forgot to mention that I have a time delay relay to switch out the start caps
A contactor? is that another name for a relay?
so the contactor feeds the idler, and then there are fuses to the load
yes and no
contactors are designed to safely switch large loads
relays are not necessarily suited for that
basically yes.. jus its really maechanical
Oh right. i have never come across them.
contactors have two contact points in series for each pole they switch, so they can't both weld closed
Right. Like a double pole switch
also, the spring is chosen so that it can break the largest theroetically possible weld you could get on the contacts
and usually strong enuf to pull themselves apart when they do
additionally, there's a guarantee (by design) that all poles or no poles will switch
on a normal relay, you could have a single leg weld shut, while the others open
I see. Are these genrally available?
search eBay for "contactor"
or motor contactor
or motor starter (might have overload sensing)
[23:59:55] <Paragon> http://cgi.ebay.co.uk/merlin-gerin-contactor-40amp_W0QQitemZ170279670113QQcmdZViewItemQQptZUK_BOI_Industrial_Automation_Control_ET?hash=item170279670113&_trksid=p3286.c0.m14&_trkparms=72%3A1298|66%3A2|65%3A12|39%3A2|240%3A1318