[Feetsalot]

I have recently conducted an experiment aimed at producing sodium hydroxide (NaOH) from a saline solution using an electrolysis method. I did this outside so as to disperse the various gases of H2 gas and Cl2 gas but I also made sure no outside contaminants, such as dirt, were introduced into the experiment. My question is: Why did the electrolysis of a saline (NaCl(aq)) solution using stainless steel electrodes at 18V turn the solution brown and create a precipitate as well as turning one of the electrodes a copper sheen and color? Also; What are the leftover products and what should I do with them?

I began by pouring 500 ml of distilled water into a 500 ml beaker at room temperature
Then I added 16 g of pure, non-iodized table salt (NaCl) and stirred with a glass stirring rod
After seeing that the solution was not fully saturated I slowly added more salt and stirred, repeating this process until I was able to see a tiny amount of undissolved salt at the bottom of the beaker
Then I securely attached my two electrodes to the side of the beaker (originally part of a broken antennae), which I thought were stainless steel, with two plastic bag clips and I made certain the electrodes were not in contact
I then proceeded to attach the dry ends of the electrodes with alligator clips to a handheld drill battery with a voltage of 18V
Immediately a large amount of bubbles (I assume mostly H2 and Cl2 gas) started forming, as expected, however a black froth (I expectt forming from an impurity) was created and about 25-30 minutes later began disappearing 
I allowed this experiment to proceed for approximately another 2.5 hours the amount of bubbles steadily decreased and the solution turned gradually more orangeish-brown (as opposed to its initial clear/white color of a saline solution) in addition a blueish-green foam formed on top of the liquid and persisted until the voltage was removed, at which point it slowly dissipated. In addition, I noticed an odd precipitate begin forming near the end of the reaction (I possibly could have missed it before).
Finally I poured the final brownish solution off into a 500 ml Erlenmeyer flask (although some precipitate was also carried over) and left the majority of the precipitate in the beaker I used for the Electrolysis. Also the electrodes which I thought were some type of stainless steel, appear to have been altered in the reaction. The anode, negative electrode, gained a dark coating, which I partially removed on one side with a scrub brush, to reveal a copperish gleam and color were it was in solution, whereas the cathode, positive electrode, remained relatively the same with some dark coating/smudging that is somewhat removable.
I have photographed all materials used in the experiment as shown here: http://imgur.com/a/X0GgS

[AWK]

Electrodes are not made from stainless steel. This is only steel covered with copper, then chromium and finally nickel. Solution at anode contains chlorine and NaoH and is very agressive tu these metals. Even stainless steel dissolve easily in this solution and hydroxides of iron, chromium and nickel precipitate.

[Feetsalot]

Thank you for the quick response! I did not expect for Cl to bond with the metals as Gaseous or liquid chlorine usually does not have an effect on metals such as iron, copper, platinum, silver, and steel at temperatures below 230°F, according to http://chemwiki.ucdavis.edu/Core/Inorganic_Chemistry/Descriptive_Chemistry/Elements_Organized_by_Block/2_p-Block_Elements/Group_17%3A_The_Halogens/Chemistry_of_Chlorine . Is there anything I can use the metal oxide precipitates for, or are they not worth while to keep? Also, in the future should I try carbon-fibre electrodes for this experiment or is there an easier way to produce NaOH? Also is there any way to separate the aqueous NaOH from the rest of the solution? Again, thank you for the quick response!

[Arkcon]

I did not expect for Cl to bond with the metals as Gaseous or liquid chlorine usually does not have an effect on metals such as iron, copper, platinum, silver, and steel at temperatures below 230°F, according to http://chemwiki.ucdavis.edu/Core/Inorganic_Chemistry/Descriptive_Chemistry/Elements_Organized_by_Block/2_p-Block_Elements/Group_17%3A_The_Halogens/Chemistry_of_Chlorine .

Respectfully, that statement is patently false.  If you've borne that out from the reference in question, then the reference is faulty, or you're misunderstanding it.  All halides are very weakening toward stainless steel.  Furthermore, you're conducting a red-ox reaction by electrolysis.  So you're not using gaseous or liquid chlorine, but instead ions under reducing or oxidizing conditions.

Is there anything I can use the metal oxide precipitates for, or are they not worth while to keep?

Oh I'd filter and dry them,if I were you.  You like to experiment, so you may find something interesting to do with this.

Also, in the future should I try carbon-fibre electrodes for this experiment

Well, a carbon electrode, say made from a common pencil or taken from a dry cell battery, sure.  Carbon fiber can mean other things, just to be clear.

or is there an easier way to produce NaOH? Also is there any way to separate the aqueous NaOH from the rest of the solution? Again, thank you for the quick response!

Oh most definitely, since you are making practically no NaOH at all.  You are making, at best, a small amount of sodium hypochlorite, that will soon evaporate away.  Look up how NaOH is made, you'll see what you're missing.

[Enthalpy]

18V is also far too much for a controlled electrolysis.

[Feetsalot]

There is a new development in this experiment. While observing the solutions and precipitate for 2 days the solution has now become clear and all the precipitate is light blue. What does this mean? Have the metal hydroxides reacted with something else in the solution? Why did the solution clear up if no extra precipitate was formed? Regardless thanks for all previous help so far and I am expecting to try another electrolysis of saline solution soon, this time with carbon electrodes and an agar+salt bridge based off this video: https://www.youtube.com/watch?annotation_id=annotation_3133827581&feature=iv&src_vid=nue1ZGSleEo&v=RjlfG1n2N2U and a few other sources.