machinery's handbook recommends drilling/reaming Aluminum at 300-400 sfm. does anyone really do this?
that means 3200 rpm for a .5 inch hole
and it said .031 per rev, so that means 100ipm feed!
I think I'd want to be standing pretty far away to try that
cradek: i usually go more on chip load, rather than pure sfm.
yeah I kept the same load (.031) but MUCH slower
maybe I did about .020, I don't remember
I experimented quite a bit because I had a part I wanted nicely finished holes in
ya definitely should spin the bit, but that high is for big ENCLOSED machines with lots of rpm and power.
I can't imagine running a .5 inch reamer at 3200 rpm
with really good (expensive) tools.
ok so the answer is "no" :-)
I think I'll continue trusting my gut instead of the book
hey, in pyvcp, is there a way to have text change on a pin change?
I don't know for sure, but probably not
alex_joni: are you home now?
I was during the weekend
i would like one big led to change color with jogging on/off, and have the axis label change on the selected axis.
cradek: well, reaming anything is done with a high feed..
anonimasu: my reamer didn't like it at all when I tried that
Roguish: what do you mean jogging on/off ?
cradek: I go by my manufacturers spec..
I dropped down to 200rpm and about 2ipm like I would do by hand on a drill press and got a very nice finish
cradek: the machinist handbook probably dosent have a clue..
i have a rotary switch for my jog wheel. when i change axis i would like the text on a label to change.
mgouget: great timing
cradek: :p seriously though, I thinkthe tool manufacturer has a better idea about it
mgouget: can you /join #emc-devel ?
alex_joni: ok, going there
anonimasu: this is just plain old HSS tools cutting Al, no idea who the manufacturer is...
cradek: random reamers?
yeah pretty much
The only experiece I have had with reamers is running too slow makes a bitter than wanted hole. ;)
cradek: how big reamer?
skunkworks_: interesting, I should measure it
anonimasu: uh yeah
0,38mm/rev is what dormer recommends..
at what rpm or surface speed?
that's whta matters..
though thoose are recomendations, slower/faster isnt as critical as long as you maintaing the same feed per tooth..
ok that seems fast to me! I've always reamed slowly with plenty of oil
this is with flood coolant :p
we ream some 50mm holes at work..
drill 49 ream 50
I have been looking at the Gecko stepper drives has anyone used these or does anyone recomend any other?
Paragon37: I have used them
they work great
Anonimasu which model would you recommend?
the "ones with v in the name"
I think everyone recommends the geckos
I havent used thoose
(but I have not used them for anything yet)
only the older ones, and they work great
* alex_joni has a small tabletop mill
XY with G201 and Z with L297/298 (pminmo design)
XY are ages better than the Z
although I wouldn't get the G201 now, I'd get the 210 or the 203V
Just took a look at the differences between the 203v and 210 the 203v has a lot of functionality but the 210 does full / half/ 5micro and 10 Micro what are the benfits for each?
the 203v can do that as well. either with the g902 (?) or it may be part of the CPLD
are you using a parallel port for step generatin?
What does the 5micro and 10micro steps signify?
Yes with EMC2
all the drives are 10x microstepping. some of them have a pulse multiplier that allows you to send one step from the PC, and have the drive go more than 1 microstep
that's for overcoming the output limits of the parport
So one can get very smooth and accurate motion?
if your motor can do 100kHz microsteps, but your PC only can output 33kHz
then you would set the multiplier, and have higher motor speeds
all the drives are microstepping from the drive to the motor
as Alex said, it's to allow a slow PC to make the motors go fast
The ones I am using currently is based on the L297 / L298 circa 1988 which only do half stepping. I guess I should see a massive improvement using microstepping
the anti-resonance of the geckos will provide a nice improvement, I think
otoh the 210 also does mid-band resonance damping
the 203v doesn't? as far as I can tell
err all geckos do.
anonimasu: are you sure?
they all do mid-band damping
if anything, the 203v will be better, since it has more logic available to make deicsions
hmm, nothing in the docs of the 203v
g203 is the MOST advanced drive they have so far.
how can I tell what max frequency the motors can handle?
as mentioned they are circa 1988
g203V: step frequency: 0 to 333kHz
can all motors handle that?
it's unlikely the motors can move as fast as the geckos are capable of driving them
certainly not while doing useful work
guess I better inquire on shipping costs to the UK then :-)
it's mentioned on the page..
though you will pay VAT on it..
No escaping that one ... :-(
anonimasu: can't see that shipping cost anywhere on there page.
click ADD TO CART
on a drive.
oh they've changed it, but it's usually around 25.
I thought it was me ...
what do you think of these £33 on ebay http://cgi.ebay.co.uk/4-2A-50V-Microstepping-Stepper-driver-ideal-for-CNC_W0QQitemZ130154526059QQihZ003QQcategoryZ42899QQrdZ1QQssPageNameZWD1VQQcmdZViewItem
Paragon37: they look cute, but no mid-band resonance damping
What does that give me sorry for naive?
read this: http://geckodrive.com/photos/Step_motor_basics.pdf
and possibly this: http://geckodrive.com/photos/How_the_G203V_gets_the_most_from_your_motor.pdf
are there drives besides gecko that do mid-band damping?
(or is that $k)
if you keep an eye on ebay - parker oem750 drives do. (although I have not had issues with microstepping drives without it.)
fenn: Yes, the parker compumorot does
the OEM650 do NOT
OEM750 brand new from Parker are $550/ea worse case scenario.
SWPadnos: With your video stuff, do you do any bandwidth monitoring?
Thanks for the links.... What does mid-band damping do in a real world sense
Paragon37: Read the links that SWPadnos gave you, it explains it very well.
Oh OK it's in there ... Thanks