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progbuddy
03-31-2007, 11:23 AM
I've just found this out in Honor's Physical Science last Thursday.

Anyone familiar with:

3NaOH + Al --> Al(OH)3 + 3Na


NaOH is Sodium Hydroxide (aka Drano). just put a little dab here and there, and it replaces the aluminum with sodium, which oxidizes about the instant it is formed. This creates a quick and easy solution for cutting anything aluminum. Just be very careful with Drano, as it has a caustic effect on skin (NaOH dissolves fats and oils; used for unclogging drains).

Drano can be bought at most hardware stores in the US, equivalents may be found elsewhere.

My teacher stuck a chunk of aluminum in NaOH, and it dissolved almost instantaneously.

I'm gonna go buy some and try it for myself :D

DaveW
03-31-2007, 11:49 AM
My teacher stuck a chunk of aluminum in NaOH, and it dissolved almost instantaneously.

Keep that crap away from my rig dude. :p

-Dave

progbuddy
03-31-2007, 12:11 PM
Keep that crap away from my rig dude. :p

-Dave

LOL.

I might use the stuff in my project if I can get my hands on some. I'll use it to cut out the two sound holes in the front and the fan holes in the sides and top.

.Maleficus.
03-31-2007, 02:58 PM
That could give a really cool effect for some toxic-themed mod. Like acid ate away at it. Very cool find dude, +rep.

rendermandan
03-31-2007, 03:30 PM
sounds a little dangerous.... I love it!

Just be carefull and do it in a well ventilated area!

Redundant
03-31-2007, 06:22 PM
That reminds me of Alien's "blood". It ate away at anything in Alien vs. Predator.

Do you think it will cut straight lines in the aluminum without eating under your straight edge?

EDIT: Does this stuff eat through steel or PVC (water pipes)?

progbuddy
03-31-2007, 07:13 PM
That reminds me of Alien's "blood". It ate away at anything in Alien vs. Predator.

Do you think it will cut straight lines in the aluminum without eating under your straight edge?

EDIT: Does this stuff eat through steel or PVC (water pipes)?

It does not eat through steel or PVC. Steel is an alloy, and PVC is a covalently bonded substance.

It will cut straight lines if you know how to use it. It will only work with certain metals though (aluminum).

Slug Toy
03-31-2007, 08:34 PM
Just be carefull and do it in a well ventilated area!

not completely necessary, the full reaction goes like this:

Al + 3NaOH ---> Al(OH)3 + 3Na

3Na + 3H2O ---> 3NaOH + 3H2

its going to make hydrogen gas, but at the scale this is being done at... its not really a problem. i do way more dangerous stuff quite regularly in the chem lab. of course... you can solve this issue by putting an open flame near it so the gas burns off steadily instead of filling a room. thats always fun... you might have intermittent bangs happening, kind of like in shop class when the idiots are fiddling with the oxy-acetylene torches.

one thing that might get in the way of this idea is the amount of drano you need. the reaction will only happen so long until the solution is saturated with Al(OH)3, and then you need to wash it off and put some more on. this may take a while.

Spawn-Inc
04-01-2007, 02:09 AM
well if i can find some drano i am going to try this! i will post somes pics if it works and i still have fingers...

Edit: dammit no drano... ohwell probably for the best.

Crimson Sky
04-01-2007, 03:41 PM
not really cutting aluminum..more like dissolving it. Wear a respirator, chemical gloves and eye protection. One splash of Drano in the eyes, and you'll be listening to forums for the rest of your life. ye be warned.

rendermandan
04-01-2007, 04:02 PM
not completely necessary, the full reaction goes like this:

Al + 3NaOH ---> Al(OH)3 + 3Na

3Na + 3H2O ---> 3NaOH + 3H2

its going to make hydrogen gas, but at the scale this is being done at... its not really a problem. i do way more dangerous stuff quite regularly in the chem lab. of course... you can solve this issue by putting an open flame near it so the gas burns off steadily instead of filling a room. thats always fun... you might have intermittent bangs happening, kind of like in shop class when the idiots are fiddling with the oxy-acetylene torches.


"NOT COMPLETELY NECESSARY" How can you say that when you are refering to a chemical reaction that will cause Aluminum to dissolve. Above all Saftey should be #1 If you are a chemist, you should know that!

I was just commenting for anybody else out there that may not know exactly the chemical reaction that is taking place and not fully understand the dangers of what they are doing. It should go without saying but as usually most people disregard the usuall. and then you talk about setting a flame to it? GIVE ME A BREAK!

Slug Toy
04-01-2007, 05:36 PM
"NOT COMPLETELY NECESSARY" How can you say that when you are refering to a chemical reaction that will cause Aluminum to dissolve. Above all Saftey should be #1 If you are a chemist, you should know that!

I was just commenting for anybody else out there that may not know exactly the chemical reaction that is taking place and not fully understand the dangers of what they are doing. It should go without saying but as usually most people disregard the usuall. and then you talk about setting a flame to it? GIVE ME A BREAK!

you know what, i should have known better. i completely forgot another part of the reaction! that one thing i didnt factor in changes everything.

new reaction:

6NaOH + 2Al ---> 3H2 + 2Na2AlO3

the reaction is intended to produce a complex salt, doesnt do anything to change the amount of hydrogen though.

not to get all up tight, but do YOU know your chemistry? think about whats going on here. at most, you're dissolving away a 120mm diameter hole in sheet aluminum in one sitting. thats 10 grams worth at most. 10 grams translates to .37 moles Al. 3 moles H2 are produced per 2 moles Al meaning that 10 grams of Al will produce .556 moles H2. .556 moles Al, through the ideal gas law (assuming standard conditions) translates to about... the volume of a grapefruit. that is pretty much nothing when you consider the fact that gases diffuse very rapidly. assuming you just ended up with that much hydrogen instantly, the worst that would happen is a loud bang. no damage. its not even as bad as a coffee cup full of acetylene. further to that, you WONT end up with that volume instantly. im sure the makers of drano know not to use something like 15 M NaOH in it, its probably more like 1 M at best, and that doent really get you a violent reaction, meaning you wont evolve gas very fast. its no faster than putting magnesium in hydrochloric acid of a similar concentration.

i dont necessarily say these things as a chemist. i say them as a person who has done this stuff before, and has the chemistry knowledge to explain whats going on. ive dealt with bromine and chlorine gas (meaning breathed it by accident), direct exposure to nitric acid and potassium oxalate (touching that stuff by accident), and many MANY fireballs and exploding beakers while making sugar based rocket fuel. i also willfully dipped my hands in bleach to demonstrate that it isnt instantly dangerous. im still here. if you set up an open flame near a grapefruit's worth of free hydrogen and put your face near it... you might lose your eyebrows, but not much more damage will ensue. if you spill drano on yourself, its not a good thing, but you have time to wash it off. it definitely wont feel as bad as concentrated nitric acid.

besides... progbuddy knows what hes doing. hes in chemistry too. he knows not to put his face near an open flame, or to drink drano... i hope.

Spawn-Inc
04-02-2007, 04:16 AM
for the most part i think safety is common sense. don't drink poison,don't get caustic stuff on your skin, etc. but there are those times you just don't know what will happen. such as what happened to me while i was drilling a hole in the bottem of a aerosol can (it was empty and open to the atmosphere when i did it. here is a link to see what it was for http://www.thebestcasescenario.com/forum/showthread.php?t=5743&page=14). there was a chemical called "Allyl Isothiocyanate" aka mustard oil inside the can and i wasn't sure what was inside. so i shook the can around a bit and i got some on my hand and neck. man did it satart to burn fast, so i ran to the sink and washed it off with cool water and aside from a little redness for an hour or 2 after i'm fine. anyway when and if my parents every get some drano i will try it with out protection as i will only use a small amount outside.

Drew
04-02-2007, 05:53 AM
^^^ best piece of advice I've heard yet...

Does seem a bit extreme.... tried thermite? That'd sort it.

Actually, don't try thermite... that'd be bad.

+rep for not actually killing yourself, and finding quite a 'unique' modding method.

Crimson Sky
04-02-2007, 07:01 AM
if you spill drano on yourself, its not a good thing, but you have time to wash it off. it definitely wont feel as bad as concentrated nitric acid.


This part is misleading. Sure if you get a little on your hands, you could wash it off and go have a Pop Tart® and watch TV. Get some in the eyes, and it reacts with the salts instantly. Unless you had an eyebath station nearby and someone to lead you to it and help you flush, you would be flailing around your bathroom screaming like a banshee, unable to open your eyes against the pain. It would begin causing irreparable damage in seconds. ;)

Drew
04-02-2007, 08:36 AM
you would be flailing around your bathroom screaming like a banshee, unable to open your eyes against the pain. It would begin causing irrebarable damage in seconds. ;)

So it would be bad then?

DaveW
04-02-2007, 10:28 AM
So it would be bad then?

Unless you're an extreme masochist, then that would be a yes.

-Dave

azminisk8r
04-02-2007, 01:12 PM
so if theres one thing we've learned in this post its to never try to pour drano while upside down

CanaBalistic
04-02-2007, 07:53 PM
Still, i'd rather use a good-ol dremmel.

godhammer
04-02-2007, 09:17 PM
Sounds kinda dodgy to me. How would it react to anodized aluminum? Also, I would imagine that it would take quite a long time. If it's a flat sheet of aluminum, or even something almost flat, I'm gonna stick with an industrial laser cutter :twisted: . If you have any experience with CAD, you can easily have almost any design cut at a local fabrication shop for a decent price (about $100 for an hour of cutting, which is way more than you should need.)

progbuddy
04-04-2007, 06:41 PM
This part is misleading. Sure if you get a little on your hands, you could wash it off and go have a Pop Tart® and watch TV. Get some in the eyes, and it reacts with the salts instantly. Unless you had an eyebath station nearby and someone to lead you to it and help you flush, you would be flailing around your bathroom screaming like a banshee, unable to open your eyes against the pain. It would begin causing irreparable damage in seconds. ;)

True. Don't mess with this stuff and wear eye and skin protection. But it does not dissolve the salts out of your eyes; it dissolves fats and oils (hence Drano dissolving the oils in your PVC piping and properties of bases and acids). I am not in chemistry, but Honor's Physical Science with Mr. Gearren sure beats the heck out of it. I'm not even to chemistry, and I'm building hydrocarbons, mole-mole equations, and complex chemical equations.

If you get drano somewhere, pour acetic acid (vinegar) on it.

(H)C2H3O2 + Na(OH) --> NaC2H3O2 + H2O

Chemical equations sure are fun :D

Also, just taking a ring of some sort to trap the Drano and something to catch the product would help the chemical reaction along.

Ichbin
04-04-2007, 09:17 PM
hrmmm....my easy way of cutting aluminum...

Tin snips.

nuff said.

progbuddy
04-04-2007, 11:11 PM
hrmmm....my easy way of cutting aluminum...

Tin snips.

nuff said.

Won't cut a clean line through 1/8 inch aluminum. My tin snips barely cut plastic that thick.

Maz
04-10-2007, 06:45 PM
hmmm, that reminds me of my remake of the Hindenburg. I had some mylar shipped, made a blimp, put some Al in draino inside of a 2L bottle. i left the cap off and stuck the flattened blimp over the top. I taped it off and away it went, with a fuse. it was really cool.

^it was for a digital media final project and i had the video edited into a short Hindenburg newscast. there were no people in the foreground though :(

oh and to the anodized Al Q: no the anodizing is a protective layer, you must react with Al. so scrape it off first.

progbuddy
04-10-2007, 09:19 PM
hmmm, that reminds me of my remake of the Hindenburg. I had some mylar shipped, made a blimp, put some Al in draino inside of a 2L bottle. i left the cap off and stuck the flattened blimp over the top. I taped it off and away it went, with a fuse. it was really cool.

^it was for a digital media final project and i had the video edited into a short Hindenburg newscast. there were no people in the foreground though :(

oh and to the anodized Al Q: no the anodizing is a protective layer, you must react with Al. so scrape it off first.

Yeah, the anodized layer is so thin you should be able to rub it off.

dfigravity
04-10-2007, 10:36 PM
not completely necessary, the full reaction goes like this:

Al + 3NaOH ---> Al(OH)3 + 3Na

3Na + 3H2O ---> 3NaOH + 3H2

its going to make hydrogen gas, but at the scale this is being done at... its not really a problem. i do way more dangerous stuff quite regularly in the chem lab. of course... you can solve this issue by putting an open flame near it so the gas burns off steadily instead of filling a room. thats always fun... you might have intermittent bangs happening, kind of like in shop class when the idiots are fiddling with the oxy-acetylene torches.

one thing that might get in the way of this idea is the amount of drano you need. the reaction will only happen so long until the solution is saturated with Al(OH)3, and then you need to wash it off and put some more on. this may take a while.



Sometimes you guys just plain scare the hell out of me. :p

Eclecticos
04-13-2007, 12:11 AM
My god. Were not talking chemistry here were talking idiotcracy.

Every heard of the Hindenburg?

We used to take wine bottles fill them with water and lye and put balloons over
. . and you would have a hydrogen balloon. . tape some long! paper towel to the balloon, lite it and let it go.

Thank you Mr.Wizard.
http://img390.imageshack.us/img390/1012/wizard2zm2.jpg
Rest in Peace: June 12, 2007 ~ 89Yrs Old.
My Childhood Hero.


But as far as using it as a tool? You'd damn better be outside.
Chemical burns are the worst kind they never heal.

Eclecticos
04-13-2007, 12:20 AM
This part is misleading. Sure if you get a little on your hands, you could wash it off and go have a Pop TartŪ and watch TV.

The funniest thing ive ever read. LMAO. . :eek: :D

m0h3k4n
06-12-2007, 06:44 PM
Im guessing the drano has quite a low molarity, so after a few hours if it eats through the aluminum in a spot and the drano pooled on the aluminum... drains, do you plan on sitting there for the remaining time constantly pouring drano over the remaining aluminum?
If you do try this I recomend having a razor blade to scrape the salt/excess drano off every 10 minutes or so and starting with a new splash.
And maybe a long book or a season of your favorite TV show to help pass the time.

progbuddy
06-13-2007, 12:52 AM
Yeah. Just think of the sick acid-burn effects, though...

Eclecticos
06-13-2007, 01:40 AM
Cutting aluminum the Easy way: With a Saw. Jigsaw, Scroll saw, Table Saw, Dremel. . ect.

silent tone
07-10-2007, 11:17 PM
I've found sodium hydroxide is highly effective at taking off anodizing. It produces a smooth, clean finish of aluminum. At least it did on the cheap alumninum part I tried. I'm not sure what alloy it was, probably 6061. I managed to find drain cleaner that was 100% sodium hydroxide at Lowes, called Roebic Crystal Drain Opener. A couple of teaspoons in about 2 cups of water stripped the anodizing off without dissolving the base material too much after an hour long soak. For parts with fine details or small threads I'd recommend a shorter time though.

For more information, google for anodizing how-tos and they usually talk about prepping the surface in this way.

Tavarin
02-28-2008, 03:26 PM
Im guessing the drano has quite a low molarity, so after a few hours if it eats through the aluminum in a spot and the drano pooled on the aluminum... drains, do you plan on sitting there for the remaining time constantly pouring drano over the remaining aluminum?
If you do try this I recomend having a razor blade to scrape the salt/excess drano off every 10 minutes or so and starting with a new splash.
And maybe a long book or a season of your favorite TV show to help pass the time.

Or you can do the easy thing and speed up the reaction by heating the aluminum first. You'll still have to scrape away the drano after it pools but the reaction will take place far faster. Or you could boil some of the water out of the drano (do this putside if you do, slashses could cause damage, and I'm not sure if the NaOH will boil ouit to) to get it to a higher concentration.

halcyonforever
04-10-2008, 02:55 PM
Chemical burns are the worst kind they never heal.[/B]

Sure they do... they just scar to high heaven.

I got hydrofloric acid on my hands because of a leaky beaker, it hurt for heck of a long time, but it did heal.

Still can't sense heat with it though...

Jarod997
05-10-2009, 05:46 PM
Boy did I come to the right place. I work in an aerospace manufacturing facility where we work with... Aluminum! Woot. Ok, what you guys are talking about is what we call chem-milling, which is an actually manufacturing process. We usually use it for making pockets in sheet material, not necessarily cutting through it.

Disclaimer: If you're going to try this, wear protective equipment (gloves, goggles, apron, etc). I'm not liable for any injuries howsoever caused by you reading this. (There, I've said it. That being said, don't be stupid. ;) )

Ok, if you're going to try it, take some masking tape and lay out your lines and apply the "Draino" in-between the tape. Make sure you flatten your tape to the aluminum with a plastic scraper or similar, or the Draino might get underneath. See http://tetontooling.net/services.html - the lower picture for an example of an industrial chem-mill template. So, if you want to be creative, lay out some tape on an aluminum surface, draw out a pattern on it, cut and remove the tape and go to your chem milling. Wash your panel with plain water when you're done. You should end up with a cool looking panel.

After you're done cutting you can either take the tape off, or try applying some sort of dye to the pattern, as you've just "eaten" the aluminum, there should be some tooth to it to accept the dye. If there's some Draino left in the pocket and you apply the dye it may just carry the dye into the aluminum -- I don't know, I've never tried/seen/heard, I'm just making this up. (But now I want to try it. ;) )

--

Oh ya, anodizing. If done correctly, anodizing should NOT be easy to remove. It's designed to protect the aluminum from reacting. -- See my post in the Ano thread for more info.