Scale removing compounds like Sparex #1

[Jeff Mack]

I use a product called Sparex #2 for my non ferrous work (ok, I use the active ingredient from sparex, sodium bisulfate IIRC, that can be had from swimming pool places a lot cheaper). It works great. A few minutes in the stuff when it's warm, and the fire scale wipes off.

I know there is a Sparex #1 for iron and steel, but the MSDS for it doesn't list the active chemical. Seems to be made of something safe. Any ideas, or anyone use something other than vinegar for the same job?

Jeff

[oakwoodforge]

Muratic acid and Naval Jelly work pretty well , but vinegar is safe and cheap. Stronger acids like Muratic or Naval Jelly call for alot more saftey gear and paying alot more attention. Spilled or splashed Vinegar is no big deal, but just one drop of Nitric acid on your arm and you ARE going to the emergency room. Strong Acids Are No JOKE !
Be Safe ! Use Saftey goggles AND face shields, Aprons, long sleeves, double up those latex gloves and above all
PAY ATTENTION !
Keep lots of Eyewash, Clean water and Baking Soda handy and If your using extra strong acids, Amonia can save your life incase of a spill.

Jens

Sorry about the saftey Lecture

[Jeff Mack]

I keep lots of baking soda handy. But, since the ingredients in Sparex #1 don't show up on it's msds, I figured they must be safe. Just have no idea what it might be.

[Woody]

Jeff:

Just because the ingredients of a compound do not show up on a MSDS sheet is no reason to assume they are safe. The reason they do not show up is because the formula for the material is propriatary information and the manufacturer don't want his product duplicated by a competetor. The stuff could contain anything including strong acids. You would be well advised to read the sections of the MSDS that contain information on health hazards, first aid and symptoms of esposure.

Woody

[Mr Smith]

Sodium Bisulphate??

Do you mean Sodium Metabisulphate? If you do, that's sold as a sterilising agent for home brewing..

If it's the same thing....

[Mills]

"but just one drop of Nitric acid on your arm and you ARE going to the emergency room"

I use Lab grade Hydrochloric, Nitric and Sulfuric acids as well as hi-grade Sodium Hydroxide. They are in my truck and are used to preserve samples that I take day in and day out.
Nitric turns your skin yellow. It will leave a surface scar if a sudden gust of wind should say, blow over the container the acid is in, onto your forearm, and you don't bother rinsing it off. Get some water and rinse.

Now Sulfuric, well that will go through your jeans as fast as that goop from the 'Alien' movie went throught the decks of the spaceship. and light up everything it touches. Does not do a very good job of taking off scale either. Doesn't bother paint too much though.

HCL is my favorite for rapid scale removal. I use it the most on the job and in smithing. I like it the least overall though. First problem is the release of chlorine, man, that is rough! Ventilation for this stuff should involve moving air and not just a big room or outside. Second, it chews on you as bad as sulfuric does. Definitely should use some glove here. Now muriatic is a watered down (dilute solution) of I believe anywhere from 10-20 percent HCL . potent stuff and straight from the jug at about 20% is very quick scale removal.
Eye protection is a biggy and remembering to not wipe your face or eyes till you have washed your hands is important as well. your lungs are the most at risk with any of these chemicals, but HCL is the worst IMO.

Ammonia, this is highly reactive with every thing! I am not allowed to bring it into the shop for nothing! I stripped our halway one time prepping for fresh wax and the lab manager was very agitated. seems that they had to go back and rerun a dozen or so samples that didn't play well with ammonia. I would like to know what exactly it will help you with in terms of these other chemicals. I don't get to mess with it much.

[Site Admin]

Safety first If you can not be safe, don't play with the chemicals. This means full face protection, gloves, chemical aprons, and the list goes on and on. As Miles pointed out, breathing the fumes is NOT a good thing and does damage starting with the first sniff.

You must know the dangers before you start and already have a plan for when things go wrong. 911 (emergency assistance) on the telephone speed dial is not a plan, it is a last feble attempt to get help.

There are people of all ages reading this material we need to continually remind them to be safe.

[Ellen]

911 is government sponsored dial-a-prayer. Most urban areas of the USA average 20 minutes and up for a response time. That can be way too long in lots (most?) of situations. If you can't be safe and knowledgeable, don't use the process. That is the beauty of vinegar. It is safer than the other chemicals; you can heat it up a bit if you want faster.

[Woody]

you should also be aware of the reactions produced when acids contact metals. Hydrogen gas is released and if it collects in an area like an attic or the peak of a roof, it can be ignited with explosive results. Yes you can have a new address with 17 different zip codes. One of the previous posts mentioned that HCL released Chlorine. While Chlorine contains no Oxygen, itis one of the most powerful Oxidizers known. It will cause other materials to ignite and burn furiously. Accodrning to NFPA Manual 491 M "Manual of Hazardous Chemical Reactions" brass burns spontaneously in gaseous Chlorine. Chlorine plus Ammonia evolve Nitrogen Trichloride gas which is not only deadly to breathe, it is extremely explosive.

Woody

[Dodge]

Wasn't aware Naval Jelly was that hazardous!! I've used it a couple times to remove rust on some pieces and experienced no adverse tramas, but was I lucky or flirting with disaster?? Instructions simply said wash with water after it did its work. But that was in the 70s when things were done "differently" i.e. drain yer radiator at the curb and run the hose a while so it didn't kill yer cat.