<azonenberg>
i want to do some SEM cross sections soon (benefits of knowing the matsci lab manager ;) )
<azonenberg>
to measure edge profiles etc
<azonenberg>
http://i.imgur.com/we2Mp.jpg was the best i've done so far for cross sectioning and optical imaging
<azonenberg>
the copper is around 150um wide and 30 high lol
<Anarchos>
so i will continue my quest of standard cells :)
<azonenberg>
my 20um features in ~1um layers wont even show up at this mag
<azonenberg>
much less provide useful slow values
<azonenberg>
and yep, good luck
<swkhan>
if i don't have a scale or a triple beam balance, how can i accurately (or at least precisely) measure out a certain mass of something?
<swkhan>
i've been putting this on hold for a while. i want to make sodium sulfate, ultimately so i can mix it with copper sulfate and get electroplated copper. i'm not sure i have all the equipment yet but i want to see if i can make some of the stuff today at least
<bart416>
Meh, use a kitchen scale
<bart416>
0.1g is precise enough for most things
<azonenberg>
swkhan: I found a scale on ebay good to 1mg
<azonenberg>
in graduation
<azonenberg>
actual accuracy maybe +/- 2 or 3
<bart416>
The issue with scales that go down to 1mg is that airflow and pressure will actually have a noticable affect
<bart416>
You need to put a cover over it to get a good reading
<azonenberg>
bart416: i've noticed lol
<XgF>
Every 1mg scale I've worke dwith has had a glass surround
<azonenberg>
breathe on it and it fluctuates by a decent amount
<azonenberg>
this has a plastic cover
<azonenberg>
its cheap, but is noticeably better accuracy than the 10mg i have
<bart416>
XgF, we were fighting for the ones with the covers during the labs
<bart416>
Except if it was something volatile that was hard to scoop up
<bart416>
Cause the cover makes that rather hard :(
<azonenberg>
bart416: lol
<azonenberg>
use a micropipette and go by volume?
<XgF>
:S we had covered 1mg scales back in sixth form
<bart416>
XgF, the covers got blown off :P
<bart416>
In miniature explosions
<azonenberg>
lol
<bart416>
Hence, some scales didn't have any covers left
<azonenberg>
i imagine it wasnt healthy for the scale either
<azonenberg>
anything that intense probably fried the load cell
<bart416>
Weirdly enough after being calibrated again it doesn't really seem to have any effect :S
<azonenberg>
o_O
<XgF>
What? The scales i'm thinking of have a steel frame which is an extension of the case, with glass plates attached to the inside of the frame
<bart416>
past a certain load it rests on a metal pad instead of transfering pressure to the load cell I guess
<bart416>
never ever use one of them to weigh blackpowder XgF!
<XgF>
Hah
<bart416>
it doesn't just lift the lid
<bart416>
it blows the glass or plastic out lol
<XgF>
Why would you weigh BP? Weigh the constituent ingredients then mix
<azonenberg>
Also, if it is spontaneously igniting you probably have ESD problems
<azonenberg>
get better grounding
<XgF>
Yeah. My BP has never blown up without me asking it to
<bart416>
XgF, mine neither
<bart416>
But some people managed it :S
<azonenberg>
was this for a class project?
<bart416>
Yes
<XgF>
Back in college I once set fire to a desk...
<azonenberg>
no fair, you get to play with explosives in class?
<bart416>
Yes
<bart416>
We also managed to crack a ceramic  table top btw
<azonenberg>
how
<bart416>
well, not we
<bart416>
Another class did during the same experiment
<azonenberg>
with BP?
<bart416>
Somebody built a miniature rocket engine with a test tube somehow
<azonenberg>
...
<azonenberg>
BP is a low explosive
<bart416>
(with something more volatile than bp)
<azonenberg>
it *should* not explode unless confined
<bart416>
It managed to knock lose a piece of metal and take it along and smash into the table
<XgF>
(We were heating some ethanol. Perhaps I was heating it too vigorously; it decided it would like to be on fire. When I was placing a gauze on top to remove the oxygen supply... I knocked over the flask...)
<azonenberg>
lol
<bart416>
lol XgF
<bart416>
Also fun was "disolve this little block of marble and calculate how much carbon and calcium it contains"
<bart416>
Oh was that one fun...
<bart416>
Half the gas captured was actually our table disolving instead of the piece of marble
<XgF>
snorts
<bart416>
Something about not providing propper equipment
<bart416>
lol
<XgF>
I also remember a bung on a tube full of conc H2SO4 (I forget the name of that particular pecie of equipment :P) blowing out in my hand...