oo i like that - detect torque via differential measurement of shaft position
anyone know of an ADC chip/circuit that I can use to input binary into the parallel port?
for about $225 I can get a PLC with an analog input card and output binary to the parallel port
any electronic wizz's about
digikey has many choices for parallel output ADCs
so many that it's mind boggling...
I should have a digikey and mouser catalog around here somewhere
10,721 items in the digikey catalog under ADC...
how many bits are you looking for, and at what conversion speed / update rate?
incidentally, if you check "in stock", the list is drastically reduced
hmmm, I want to convert my arc voltage signal to I'm guessing 8 bits
ok, the ADC is the least of your worries then, I think
I know that I have to use a voltage divider circuit to scale it down to 5 or 10 vdc max
isolation and level shifting will be much more cahllenging, as well as noise reduction
the source is not from the arc circuit but from a arc signal circuit from the controller board
ok, that's a good thing :)
do you know how clean it is, or whether you need isolation?
would it not be kinda not noisy?
not really, I don't have a scope anymore
not necessarily, if it's near a high voltage/high power switching supply for the plasma
it is designed to plug into a torch height control
what kind of sample rate are you looking for?
I have not done the math on that but fast enough to update the torch height while cutting
I'm not sure that you'll want to do that in software.
I don't know though
why is that?
I don't know how touchy a torch controller has to be
what I would be adding is one thing to Dallur's hal file
I'm betting faster than 1ms though, and you'll have to do some testing if you want to use FP in the base thread
(due to latency, not any specific technical problem)
instead of up down, I would input a binary number
what is FP?
I may be overthinking it - I just came back from a customer who needed an extra HAL parameter and error checking for "load resistance too low" :)
in Dallur's case he is doing everything but comparing the input number to a preset number
using pyVCP to input a voltage number then compare that to the binary number on port 1 and adjust up or down as needed
if it's more or less about keeping the plasma a certain distance above the wrok, and it's controlled by a Z motor, then it could work
that is my thought process at the moment
yes, that is exactly it
pyvcp isn't even close to realtime, it all runs in user space
think about that a bit before continuing :)
I just set the preset in pyvcp
hal does the compare
I've actually got all the hal part worked out and tested
my next step as I see it is to use my lab power supply to feed an ADC circuit to test that part but I need to come up with an ADC circuit/chip
I think the next step is to find out what kind of interface and filtering might be necessary to connect to that output
the output of the plasma torch?
if you see that you need isolation, then you may need to use a serial A/D or a microcontroller
a THC may be expected to have plenty of protection on its input - I don't know for sure
how can I find out what I need?
ideally, from manufacturer spec sheets
for the plasma and /or THC products
do I need to scrounge a scope?
a meter might also do it, or looking at the components that drive the output
I didn't see any thing on my plasma but I'll look at some of the THC products and see what I can dig up
isolated analog isn't too easy, so I'm suspicious that the output isn't isolated
step 1: define the problem. step 2: figure out the solution :)
step 3: profit!
profit what is that?
dunno - I keep forgetting that one
so worst case I have to buy a PLC and use that to convert from analog to digital
that I know I can make work
heh - that would be the worst case, I think
but if I only need $50 worth of chips and parts I'd rather do it that way
SWPadnos: i'm having trouble going from 2 to 3
$50 should be enough, even if you need isolation
fenn, yeah, I know the problem. haven't figured out a good way around it though
on the emc side I'll use wsum to convert the binary input from the parallel port to an integer
then convert that to a float and do a comp on the setpoint vs the actual
* BigJohnT hears the dinner bell ringing and I'm never late for dinner bbl
mmmm, chicken n dumplings perfect on a nasty winter night
i totally do not understand the chain rule, derivatives of exponents, derivatives of e and log functions sigh
SWPadnos: do you design ECM generators/controls?
well, sort of, indirectly
but not the hardware or "design" - I implement the software to do whatever the deisgners think they need
ok, i was looking for an opinion on pulsed dc current sensors
hmmm. I'm not sure what they used
the scale may be off by a few orders of magnitude as well ;)
My application is 28-32Vdc 300Apeak. Max cycle 300uS 'on' (discharge) with 50uS 'off' (pause), so near 3Khz. Shunt voltages too noisy, so i looked at http://www.vektrex.com/Products/sensors.html.
I want to stop the process when a threshold is exceeded.
)i had that ready for someone to lok at ;)
ok, only ~2 orders of magnitude low ;)
this is what was used, I don't know what brand: http://en.wikipedia.org/wiki/Rogowski_coil
thx, new to me ( was looking in the magnetic sensor area)
yeah, the name was new to me as well, though there was a paper about them from about 1912 (according to wikipedia)
google told me about this company: http://www.pemuk.com/index.html
yeh, that flexiprobe looks expensive ( hp always were )
that advert moved away from any dc claims ( most CTs do )
tomp: have you looked at hall effect sensors?
these are hall http://www.vektrex.com/Products/sensors.html
and they seem to be the magnitude needed, a laser stack user quoted success at 32V 300A
[04:52:02] <jmkasunich> http://web4.lem.com/docs/products/LA%20255-S%20E.pdf
i'd hope that a comparator with a setpoint would handle this ( a stop gap bandaid till the generator design is fixed )
the one I posted is one of many - list of product ranges they make: http://www.lemusa.com/hq/en/content/view/269/206/
thx, damn fast, the 32ohms worries me, will look thru thier offerings :)
oops, that was secondary coil, not seen by process
LF205-S looks like it would work too - cheaper
we use LEM sensors in drives, I think I've used the LF205 a while ago
we mostly use LF505, LF1005 and LF2005 for the drives I've been doing lately
thanks, those look good, i just gotta find one with a bigger hole :) 4 flat cables gotta pass thru. looks great
hmm, no , can use a busbar , even better
the surfaces that I mill come out horribly rough -- is there anyway to fix this automatically?
do you have pictures
darn, should've thought of taking pics
can you describe the roughness
does it look torn, or pulled apart?
I have a cylindrically shaped mill tool, whose bottom is flat, and I use the tool to carve out a small rounded rectangle well (pit) in a block of acrylic
scalloped may be the right word
what's your feed, speed, and size of the endmill
unless you're really careful, acrylic will always look like shit
because at the bottom of the well that I mill, I see circular lines indicating the path that the tool bottom took
you will always see those
your millhead may not be square (trammed)
you can slow your feed down a lot, and speed your RPM up
but i doubt you're going to eliminate all the tool marks
so in the world of milling, one will always see the tool marks?
SWPadnos: 'trammed' meaning a tool defect?
trammed meaning head perpendicular to the table
no, "trammed" meaning that the spindle is perfectly perpendicular to the table movement
squareness of spindle axis to x y travel
if you have some kerosene you can brush some of that on
that will help
wd-40 also works
mount and indicator in the spindle, swing over table, adjust till reading same n/s/e/w
are there specific materials that those two work on? or can I use this on acrylic?
give it a test on a scrap piece to make sure it doesn't discolor
you can tell when the machine is more or less trammed corerctly when you have about the same number of circular marks in one direction as the other (ie, there's no real bias toward marks from the right side of the tool vs the left)
but it should work perfect
swpadnos: he wants the tool marks to go away
understood - tramming is important for that - you have gouges with really bad tramming
tramming it will make it worse
unless it's way out
err - not in my limited experience :)
in my less limited experience it does
the back drag tears the material and leaves a crappy finish
[05:24:48] <tomp> http://www.jjjtrain.com/vms/mill_movements_head/mill_movement_head_00.html
if you bump the tram out just a bit, .002" or so
leaning into the cutting direction
hmmm. maybe I always use perfect machining practice, so I don't have that problem
you will get a better finish
but wd-40 or some other similar thing will work great
SWPadnos: meaning that you never have to polish up the part that comes out of the mill?
and it should work for acrylic
no, I still have marks :)
a very sharp hss tool
i can make a part on a mill where you can't see the marks
hss, high speed steel
versus a carbide tool
maybe acrylic is a bad choice of material
well, not really
anything you cut is going to have tool marks
especially in a pocketing operation
the only chance you ever have on a mill to remove obvious tool marks is on a flycut
and that only does large surfaces
the sharpness of your tool, the speed it spins at, how slow you feed it, and how lubricated it is
are going to be major factors in your control over surface finish
the spindle bearings are something that also has a very large contribution but isn't in your control
can't see as in producing an optically clear surface in acrylic?
the last three I can control, but I'm not sure about the first
maddash: use a new tool
ds2: if it's possible, yes
you aren't going to get an optical surface from milling it
hm, what process would be required, then?
polishing the darn thing
mill a mold, and use cast acrylic
you'd have to polish the mold
how would you polish the inside of a pocket?
does that mean using sandpaper? ugh.
maddash: try skim cutting a piece of junk material, got scallops? you'll have same in pocket bottom, problem seen on skim is not depth related, check head square to table motion
ds2: carefully, with sandpaper/very fine grain files
riffler/die sinking files
y'all are assuming the mold is out of metal
Jymmm: silicone molds work on acrylic?
i am assuming he's casting plastic and it's going to take on whatever surface finish the mold has no matter what material?
unless you've got an idea to create a mold with a great finish from the get go, which i would not pee on insofar as ideas go
Jymmmm: omg, "cast acrylic"? that's waaaaaay out of my league
i just don't know any methods to produce an optically smooth mold without polishing
in any material
i'd get a bunch of sandpaper and a lot of wd-40
and wet sand it.
maybe I could rig my mill to do the sanding too
and eventually work my way up to polishing cloth/diamond paper
guess laminating it is easier then polishing acrylic pockets
ds2: Create an account http://cyro.custhelp.com/cgi-bin/cyro.cfg/php/enduser/acct_login.php?p_sid=Uf4MM5Yi&p_accessibility=&p_lva=&p_sp=&p_li=&p_next_page=std_alp.php
lamanating is a good idea
why does this have to be see through
toastydeath: it's going to be a fancy birthday present for my ex-ex
can you make it in two parts, so you can use a "frame" with translucent pocket borders
and then use a stock piece with the optical finish as a faceplate
and use like chrome bolts or something to hold the two together and still look fancy
come to think of it, it doesn't have to be transparent, translucent is good too. maybe opaque could work, as long as those horrid tool marks don't show up
sand it, it'll go translucent
and no tool marks.
toastydeath: I'll try your lube/rpm/hss advice tomorrow, thanks
those marks ain't going away, it will just be less sanding
toastydeath: going to try to make some keychains and I want to protect the engraving
oh, for laminating?
I want to create a clear pocket to glue over the engraving
so instead of doing it as one pocket, I'll get flat stock with a center cut out and a thin clear peice
and glue the 3 peices together
yeah, that's a much saner plan
btw, those roper/whitney clone punches from HF are amazing things for sheetmetal work
Question. What is EMC_TASK_PLAN_RESUME and how do I get rid of it if I don't want to resume?
I think that's the NML message sent (by the user interface) to continue after a M0 (in gcode) or EMC_TASK_PLAN_PAUSE (via NML)
I'm seeing now an EMC_TASK_EXEC_WAITING_FOR_MOTION_AND_IO
The confusion is that I don't think I asked for it to sit and wait for some external signal.
Is there a description of motion and IO around?
at this point I'd be forced to start searching around in the source files..
looks like the only places that EMC_TASK_EXEC_WAITING_FOR_MOTION_AND_IO is set is in emctaskmain.cc
What the ...
So I seem to be sitting waiting for some IO to complete so that motion can take off again.
This is with a tool change and a spindle start.
But I commented both of them out and still get it.
Thanks again Jeff.
is it waiting for tool-changed or spindle-at-speed?
I was wondering if spindle at speed might do it but didn't see a problem.
* rayh looks again
which tool is active, the new or old tool?
could give some hint where you're stuck in the tool change cycle
Well spindle is on
spindle speed out is 5200
brake is off
and and halui says tool #1 so the change has completed.
rayh: might be a HAL thingie which sets feedhold until at speed
or a foobar in the NML comm
I don't see a spindle at speed here. This is 2.1.7
maybe spindle-at-speed was never implemented
This behavior is really strange. Perhaps I'll recompile a 2.1.7 and try again.
Thanks for the help guys.
Hey rah - good to hear from you again
Hey. you as cold there as we are here.
* skunkworks is not hearing from the sun god
no - finally
yikes - +5 here heat wave
It was cold this weekend.. but not that cold
Wow. Hope it gets here before long.
snowing again :0
And a 40 mph wind on top of those.
yep -sounds like what we had sunday
You have had more than enough snow.
yes - I don't mind though.
an acutal real winter
Keeps the riff-raff out?
heh - and the crazies on the ski hills
good morning. what is 'teleop' mode as compared to 'free' and 'coord' modes?
teleop lets you jog axes instead of joints on a kinematics machine
ah, hello cradek. thanks for the explanaition. i just read a brief description in motion.h
'lo, anyone here?
that's tthe spirit!
t seem to find the documentation for the auto-tool measurement that cradek did
gah, damn keyboard with a messed up layout and huge return key ;)
tool-length-probe.ngc I believe, in the nc_files dir
oh, a sample .ngc file
if an axis can be jogged in teleop mode, why can't it be homed in teleop mode also?
Roguish, because homing uses the free mode planner ;)
howdy, the video about the rotary broach tool, that does require significant horse power to perform, im talking lots
broaching uses very small changes in tooth size, so you're shaving off ~0.010 thickness per tooth
ive used that particular hole to make square holes before, its a lot of power required
I did broaching of aluminum keyways on my bridgeport by sticking the broach in my spindle and crankingthe knee up
oh yeah, but thats a lot of power there as well
no, not lots of power, good force multiplication
its more then say a sherline lathe can do is what im saying
it was still the 0.3 or so HP I can generate with my arms (on a good day)
well, yeah with aluminum, but once you get into steel the requirement goes up
possibly. the canted angle of those broaches may act like a chip-breaker, so you're only pushing one tooth at at time
There is no reason you can't do rigid tapping on a lathe - right?
yeah, thats to help break the chip, when it roates at a wobble its compressing then shearing off a chip
(with the tap mounted in the tool post)
(as long as emc can reverse the spindle)
bbiab - I have to go commune with my morning coffee
SWPadnos: imm havine mine now
skunkworks: its still a good practice in a lathe to use a floating holder to make up for any slight missalignments
the stuff smells so good when it's brewing :)
I guess my experience on machines is different for a ridgid tapping on a lathe v. mill application because most lathe spindles have a lot more mass, designed to spin a large dia work piece, so the resulting slow/reverse gets tricky, especially at higher rpms but I guess at home a lathe spindle is going to be much like a mills spindle
much of a lathe spindle's inertia in in the chuck
I saw a small Mazak rigid tapping at 4500 rpm in plastic.
I'll bet it barely got to speed before reverse.
that is why small collets systems are nice
This one had a small chuck and was bar feed.
no floating holder?
but plastic bar
nice, im not saying it cant be done, all things are possiable, im just saying that its more dificult normally
Sure. And a ten hp servo spindle makes a difference
just a bit different than my 2 hp lathe spindle ... 240 v single phase ;-)
still done carefully it should thread decently
be back in a bit
we where rigid tapping aluminum with the mazak
at the workshop
*we - as in the emc developers.. ;)
That was great work.
[15:59:41] <skunkworks> http://axis.unpythonic.net/01181942178
yeah -how did you like the stepped screws? :)
(useless but cool :) )
Right. How about pipe thread with a variable pitch?
hmmm. it would have to be small pipe to fit on the Sherline ;)
Hey did that cold weather get to you yet. I sent it your way.
thanks, I think we have a little of it
but not as bad as you were describing
cradek: thanks for adding the ';' comment line!!!!!!!!
Roguish: joints and axes are different things
you can't home an axis, period.
except when you have trivkins, and everyone calls axes joints and vise versa
sure, when anything can be everything for everyone, anything goes
fenn: ok. i see that. i am getting wierd behavoir with the 5 axis configuration when using tkemc and axis. the behavior are different and i am trying to figure out what is going on so i can ask
im going back inside now to work on cooking and some math, well lots of math
more intelligent (less stupid) questions.
there are no stupid questions
only stupid people asking questions ;)
gezar_: rotary broaching doesnt require any particular amount of power, just enough torque to cut off a decent sized chip (as with any metal cutting)
</8th grade jokes>
oh yeah there are!!! color me stupid sometimes then.
teleop is poorly tested and definitely buggy
fenn : power torque but true, in 4140 a 3/4" square hole broach can pull 40% on a 25hp spindle
Roguish: you're welcome
fenn thats what the load was when broaching 36rhc 4140 was with a 3/4" broach made of m2
like i said, there are problems going from joint to world mode and back. it seems that some of the numerous 'home' flags may not be getting set or cleared.
machine didnt like doing it at all
ok, 10hp seems high
fenn I dont know what its like to do in softer metals, but yeah, probably not much work at all
Roguish: G0 X1 (MSG,It was interesting; this can't be a comment); but this is
gezar_: generally i think of HP as how much a certain tool can handle before it liquifies
sure. ';' must be in the front of the line not mid-line. that's ok fine.
you mean surfacefootage?
no, it can be anywhere in the line
gezar_ is now known as gezar
no I allowed it anywhere
but a semicolon in a () comment doesn't count as a comment char
that was the "fun" part
gezar: what i'm saying is there's not really a minimum power level for any particular cut type
because you can gear it down
there's a minimum force, which when integrated over time gives you a minimum power (so for a given cut, to do it in some time, you need some minimum power)
oh. ok. that's ok also. ';' anywhere on the line except in a '( )' comment.
fenn yeah, thats true for sure
no, haha, they're allowed anywhere, including in () comments
gezar, you can derive all this stuff with that calculus homework ;)
otherwise the change would break existing programs
except in message?
im not saying its not possiable, im just saying that to do it on a small home made lathe its not going to be easy
Roguish, you can put a ; in a () comment, but it doesn't make the rest of the line a comment, the ' is just part of the message
SWPadnos: its killing me man, practiable application != formulas a lot of the time :)
so you could (msg, change tools; then press start)
without an error
except from the punctuation police
otherwise the ending parens would be nmissing and stop the program
gezar: rigidity is the issue then, or maybe torque but i doubt it
unless you're broaching huge forms
[16:13:51] <skunkworks> http://www.cnczone.com/forums/showpost.php?p=408985&postcount=101
we ended up going with a single point tool to do the broaching
rigidity is resistance to deforming under force (/ pressure)
i just wanted the front of the line, but anywhere on the line is way more better.
during the rotary broaching, it would make the turret twist
is it just me or does this tap have a surprising twist to it? http://axis.unpythonic.net/files/01181942178/img_6417.jpg
but if you can index your spindle, then a single point tool taking .003 or so a wack makes broaching in a lathe easy
that's pretty twisty.
who made the '5axis' utube video and what software was used to catch the images?
I wonder if our hole was undersize
that picture isn't getting here. I think we are overloading poors jeplers site
i got to that link. thanks. i will try that for my 5axisgantry.
okay, off to do my homework
cradek: I really doubt if that tap is twisting..
yeah but it sure looks twisty
you can follow the flute up - I think that is what it is.. (the flute is exiting the tap)
(if that made sense)
you might be right
you can actually but a spiral flute tap,has much more twist than the 1 in the pic
osg has them
yeah they're good for blind holes
yes,they sure are
it is cool seeing the shavings come strait out the flutes of the tap.. (of the spiral taps)
I can't find bitlbee in lenny repo. was bitlbee removed from lenny?
boy konqueror sure didnt like showing that progressive jpg on my little computer
i learned something last night from the mazak demo ini on homing,instead of my sequence being z,y,then x it now homes z,then x and y simultaniously
looks like a store bought machine homing out
wish my store-bought machine would do that :-)
not enough computing power available I guess
wish i could buy a machine in a store
they dont seem to have any around here
fenn: well more like "someone bought it from a store when I was in grade school"
ah, cradek is here, excelent
eta is now known as lern_hydra
I'm trying to implement a tool length probe function in my CAM app
I've been looking at your tool-length-probe.ngc file a bit
does touch-off use g54 and/or will it work with g38.2?
my scheme is this: with no TLO in effect (G49) touch off with the first tool. This one now considered zero length
at tool changes the difference between the original tool and new tool is calculated and TLO is given that number
Ah, I see
hmm, where are the G30 coords defined?
what is G30
some type of predefined coordinate (you used it in your ngc file ;) )
oh G30, right
go to alternate reference point position
just set it over the switch
anyone qualify as a 5i20 expert?
dave_1: just go ahead and ask your question
when asked point-blank, nobody who's smart will claim to know anything!
long sad story ... my motenc card just went down ... it holds the bus down so computer won't boot. :-(
unless he's trying to sell you something maybe
cradek, how do I set it over the switch?
so ... I need to fire up my 5i20/7i33/7i37 which I've never used
lern_hydra: don't make me URL you
does anyone have a suggestion on a good breakout board ...
and are there pics/instructions someplace to make cabling easy
cradek, O_o it doesn't say in the manual, it says how to config in a gcode file, but not globally
those parameters are saved, so once you set it (even in MDI) it will be set forever until you change it
in trunk, but not 2.2, I've made G30.1 (and G28.1) which set those parameters to the current position
otherwise I think they're a pain to set
oh I see
dave_1: the pinouts of the m5i20 are in the emc pdf manuals, the cheap<er> breakouts are from http://www.daqstuff.com/
tom1 ok, since I don't need opto isolation
tom1 I just like the instructions for dummies ... P2 on "xxx" goes to P2 on "yyy" , etc.
dave_1: any one thing that took it down do you think?
dave_1: anders wallin has diy opto iso brkouts ( i spose you could jmp across the opto pads )
don't see that I want the opto ....
the '33 talks directly to the encoders and the amps
and the '37 is opto already so I think I'm set
skunkworks ... no hint what took it down .. I was shutting down and firing up ... emc ... working on setting for homing and all of a sudden it wouldnt boot
has to be the pci chip on the board ... tried two different motherboards
tom1 are all pins individual or do they gnd all even pins
dunno dave, its in the docs & i gotta fly
gonna run also .... have fun ...
[18:10:52] <alex_joni> http://businessclass.org/truthaboutinternet.jpg
eta is now known as lern_hydra
back again, can't seem to find (neither in the wiki nor in the user manual) any way of doing an incremental move, anyone know the syntax for that?
ie. incremental_g0 Z5 moves the Z axis 5 units
G0 Z5 G91
and G90 to restore to absolute positioning
oh, so it's modal
if im not completely mistaken...
yep it appears to be modal
anyone familiar with working with .dxf files and can assist me? I am not a cad user and disabled and was told the drawings I had made from pdf need to be corrected so the parts fit together
I was just about to say something!!
archivist: anything new?
I had to change my gear prog to match the extra axis today
I must fit some homing switches and measuring to improve the cycle
what is the link to your sit again? (cnc pictures and such)
will be noo vid later when uploaded
not added this weekends work yet
won some useful parts today http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&rd=1&item=180213396882&ssPageName=STRK:MEWA:IT&ih=008
thats really close to the end of the internet
and this to get ideas at this week http://www.devicelink.com/expo/macbuild08/fairataglance.html
Anyone have a link that has small parts for Dumore TP grinders? One of my dumore spindles came with a 1/8 thread on type collet that's been spun out and overclamped :o( to death.
[21:13:14] <SWPadnos> http://www.dumorecorp.com/
I'd been looking on the dumore site and hadn't received an e-mail back. Tried travers and mcmastercarr sites..
homemade tamales are so good
gezar: what speeds & feeds do you use for tamales?
10-20sfm with a feed rate of about 1 corn husk covered and wrapped /min
they are not nearly as hard as I had originally thought they were going to be to make
gezar: you have to promise to paste the g-code for tamales :O)
and I cant understand how the last 10 places ive ordered them at have managed to screw them up so badly
I will, this was my trial run, so ill post a beef one how is that?
I used some leftover chicken that I boiled down
it wont be iso standard Gcode is that okay?
*(&^ just got outbid again on a ballscrew.... anyone here just win an NSK basslcrew auction?
as long as you use proper mcodes, i'll be okay with it...
SkinnypuppY34: dumore 1/8 collet http://www.jlindustrial.com/DUM-70066A/SEARCH:CATEGORY/product.html
SkinnypuppY34: what size screws you after?
Woah tomp good dig! thanks
be sure b4 buying
gezar something to drive the quill on my bp clone http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=150211343552&ssPageName=STRK:MEDW:IT&ih=005
oh wow, your thinking about using a screw and some how attatching an arm to the quill?
how else would you do it
directly into the existing rotary gizmo
Yep, hopefully attaching to the adjustable stop's location I've seen others with a clampon foot around the spindle
I guess my way isnt very accurate though
I though of it but there is a little play in the handfeed
lots of backlash
clamp on foot would give you some mounting freedom
then you could spin the nut...\
i was thinking about that, one of those through hole steppers?
or servos, who knows
lock the depth nut& jam nut on left of BP, then see your blacklash by feeling the hand feed lever on right
no, that'll show the slop in the feed gear...
i think the depth nut is against a boss on the quill cylinder, then there wouldnt be any Z lash there
jmk has a drawing of Z with a spinning nut
there's a spinning nut design for mini mills...
[21:51:06] <fenn> http://jmkasunich.com/cgi-bin/blosxom/shoptask/Z-axis-12-16-06.html
I was just looking at the turn to Z travel , one turn gives me 3 1/2 " quill travel
uh, that's a spindle conversion?
Looks pretty nice
spinning nut http://www.stirlingsteele.com/millplans.html
uh, right fenn
SkinnypuppY34: the thingy that gives you 3 1/2" is sloppy, jmk's design is cnc-worthy
maybe put one of those boyscout collapsable cups over the exposed screw ;)
OIC just looked at the JMK design
Here's one of the conversion threads I had ideas from though I think I want to mount onto the machined pad the depth rule is attached to instead of the four clamping bolts http://cnczone.com/forums/showthread.php?t=8749&highlight=j-head+conversion
that's how some of the Anilam quill drives mount
On that machined pad?
the bolts are used to hold it down, but the mating surface is that lip at the top/bottom of the scale drive nut
in fact, the drive is a peg that goes into a hole on that bushing (that the depth stop ring goes to)
I can take some photos of the Anilam quill drive I have if you like (but probably not for a few days at least)
Good to know looked to be the best datum to work from , jeez an expanding plug what what I had in mind
Sure thing I wouldn't mind seeing
it's not the best way, but it is good, considering what's there
I think I have to drill / tap some holes in the millhead though, which is part of the reason I haven't mounted that yet
What all do you have on your mill? I've been enjoying my 2 axis steppers and need to get in gear on the quill
I have handles ;)
I had handles nothing wrong there ;)
I'm going for the "machine retrofit procrastination" record, so it may be a while before I put the servos on :)
you have that problem too?
what problem? :)
I sure do , that and cheapness has led me to months with no Z ..
swp what were you going to make that got you into cnc anyway
some heat exchanger or something?
I want to build one of these http://www.trevormarshall.com/waveguides.htm
hmm "Really folks - plus or minus 1 mm will not kill your antenna!" er depends /me is into microwaves a bit
+- 1mm sounds like a mile to me
mm wavelength is ~300GHz, so it shouldn't matter much on an antenna
Ide like to test one on my network analyser to check
a mm error in width of the slots will change the impedence match, dunno by how much though
ok, in waveguides it could be a problem ;)
and iirc some slot antennas use a phased refection from the ends, he has loads to dump it
if it all goes out the slots none will get to the ends
Anyone familiar with roton ballscrews? http://www.roton.com/Mating_Components.aspx?family=7059321
heard of them, never used them
there was a recent thread on CNC Zone about them: http://www.cnczone.com/forums/showthread.php?t=51159
gotta go, back later
SWPadnos, do you recognise the center bottom testgear item on that guys page looks a bit like a scalar network analyser to me
[22:59:02] <archivist> http://www.trevormarshall.com/waveguides.htm
or a vector network analyzer
Roton maybe not "Roton ballscrews are C10 or T for transport grade,lead accuracy .009."
good night all