Well well, well. It's Halloween. What would Halloween be like without blood effects? As much as I may despise this "holiday" it is Always fun to MAKE something awesome for a costume or just something to scare the crap out of anyone. I mean, that's what it's all about right? (or is it massive sugar rushes...?)

So we get onto the instructable itself.

Now, before I go any further, we are dealing with CHEMICALS. Yes, that's right, CHEMICALS! they may be awesome, but as a disclaimer (though these are not volatile, nor caustic) I take NO responsibility for your stupidity. One of the chemicals is a TOXIN hazard. AKA don't drink it, it's not good for you. Also, the final blood product is kind of like medical iodine, it WILL stain, and takes a fair amount of washing to get the color out of your skin. No burns, but toxic, and stains. Act accordingly.

This might also not be something smart for children under 10. Stick with red cool-ade.

That said, let's have fun! This can be used for special FX in movies and not only Halloween! For hair raising blood effects, I've never seen anything like this! It's so crazy close to REAL blood that you'll have your neighbors dropping their mouths and dialing the local hospital for an ambulance!

Even better, this requires no pumps (heart included, we're not actually cutting ourselves)

So what DO we need?

Step 1: Materials

Here's what you need.

Potassium Thiocyanate
Ferric Nitrate
Two plastic spoons
stirring rods (can be spoons)
shot glass
water
two containers to put your two part blood in. Should be easy to seal, and easy to carry.
Paint brush (optional, but recommended)
dull something to "cut" yourself with

Don't know where to get the chemicals? look here:
potassium thiocyanate:
http://www.hometrainingtools.com/catalog/chemistry/chemicals/chemicals-m-p/p_ch-kscn.html

Ferric nitrate:
http://www.hometrainingtools.com/catalog/chemistry/chemicals/chemicals-d-l/p_un1466.html

30g lasts a LONG time, and makes one heck of a lot of blood. Maximum you'll ever need is two bottles of each... unless you intend to bathe in the stuff... (see stupidity disclaimer)

Step 2: Add Water

Simply, fill the shotglass, and dump it once into each container.

Step 3: Add Chemicals

Make SURE to use separate spoons for each! otherwise just the dust will react and color your solutions! (which is not good)

The pictures show about how much. It's not really much at all.

Oh, and pour over the sink... it's easier to wash out that way.

Step 4: Mix

Take your stir rod (or spoons) and sir until the crystals are completely dissolved.

Brown solution is the Ferric Nitrate, Clear is the Potassium Thiocyanate.

Step 5: Apply!

Using the paint brush, "paint" the clear solution all over the area you want to "cut".

Step 6: Dip Knife

Simply dip your blunt object in the solution, or, apply it to the knife (easiest) I used the stir rods to drop it near the tip.

Step 7: CUT!

As a general tip, the proper technique to cutting is to press with the tip, then slowly lower the knife until the wet part touches. Slowly drag across skin to "cut".

It also should be noted that it is best to point the wet side away from the camera/person to give a better effect.

So, here's a video of the knife in action!

(above video should load in a few hours, it's being processed link below)
http://s19.photobucket.com/albums/b154/thecheatscalc/?action=view&current=Howtodoit.flv

Step 8: Safety Issues and Concerns

well, it's been mentioned that "hey look at the labels of these chemicals! they don't seem healthy? do I want that on my skin?"

in short, the rule of moderation applies, a little bit, for a little while, isn't going to cause harm.

Keep it on your skin for a very long time, well... all hands off!

Please, use at your own discretion! However, even if you don't want to put it on your skin, think about where you could put it.... poor jack'o'lantern...

Here are all the health concerns that need to be addressed:

Fire- no issues, we're diluting it heavily in water.

Oxidation- minimal. Unless you leave it on there, there should be no/minimal oxidization. That said, wash your knife anyways. This isn't like some CERTAIN other chemical reactions...

Poisonous gasses- nothing to be concerned about here. If you even have ambient air flow, you don't have a thing to worry about. If it produces gasses, they're produced too slow to be a problem and will be completely dissipated. Unless you live in a small air tight box, but then you've got other problems.

Toxin- Yes, it's poisionous. How much? unknown, I'd assume it's not life threatening in the diluted form that we're using, and at most (unless you're drinking these) will have an upset stomach. Don't be licking your "wound"...

Please note, lethal dose 15g-30g, that's half the bottle! and that's taking it straight! we're only using about 3-5g grams at a time. No issue.

Eyes- keep out of eyes, ears, and other orifices as well as cuts (duh) would you rub soap in your eyes? (or real blood for that matter?) no, back to the stupidity disclaimer.

Skin contact- Well, here's the main issue I'll assume, once again, we're DILUTING. This means- deconcentrating a solution ( :p )
Redness-none
Swelling-none
itching-none
rashes-none
pain-none
incurable diseases- none

Seriously, the safest way is to keep yourself clean. It's the easiest way to keep yourself safe. I have no doubt that with the current concentrations you could cause all of the above problems, but, these will be from multiple hours of exposure. For any short amount of time, these won't be an issue. Unless someone can prove me wrong, I'll stand by that these are harmless for their "intended" purpose if the directions are followed. When you're done, wash skin throughly. Besides, you have to anyways if you're going to do it again, right?

Also, because their is a chemical reaction, generally both original chemicals lose their properties. (such as chlorine and sodium into salt) The final blood should have even less to worry about, as you're removing much of the original dangerous properties of (really mainly) the ferric nitrate by adding a base (potassium Thiocyanate) and also removing it's properties as well. Keep that in mind as well.