FourWheelForum

FourWheelForum (http://www.fourwheelforum.com/index.php)
-   The Honda CA95 / Benly 150 Restoration (http://www.fourwheelforum.com/forumdisplay.php?f=24)
-   -   Rust Removal (http://www.fourwheelforum.com/showthread.php?t=1928)

JoeM 02-02-2013 04:33 AM

Rust Removal
 
I know some of you are aware of this because I've seen it referenced in a few threads, but I thought I would post a thread with my experience.

Removing rust with molasses. Google it, you'll find lots of references.

Heres a nice YouTube video.

I've done this for a few years. I have a big vat ( a Rubbermaid storage container ) filled with a 10-1 mixture that sits under my workbench.

I've put all sorts of things in there, nut&bolts, engine/frame parts, chrome parts. They come out clean clean clean. My earlier experiments were with the absolute worst rusty old car parts I could find. I was amazed.

Now, this removes rust, it does not "make metal". So severely corroded parts will come out clean, but pock marked where the rust was eating deep into the surface. But the task at hand was "rust removal", so that's what you get.

The trick people neglect is t...i...m...e... I've soaked parts for up to 4 months. It literally is "set and forget" (literally, I've forgotten about things I've put in there when I switch projects). I've never encountered a time period where "too much time" damages whatever part I put in there. That time may exist, I'm just saying *I've* never encountered it.

A friend of mine soaked the inside of a KZ1000 tank for a few months and it came out shiny clean.

Of course, for small quick jobs I use EvapoRust. Great stuff, same principle. But you'd never afford a vat of that stuff :)

ByTheLake 02-02-2013 05:03 AM

Interesting, never heard of that. Seems to work well in the video. My only issue would be the need for patience - waiting a week (or several weeks) for the results. I used Metal Rescue, which took 24-48 hours, but certainly cost more than the molasses option. I know Spokes used another solution, too.

Thanks for sharing the tip.

Smithers 02-02-2013 09:29 AM

Awesome! I'll be using this process for sure. Here is another video I found where the guy throws in some longer parts from a classic car in some storage bin as well. He said 4 or 5 days to process his parts at the beginning. I'm sure each case is different but that's a method I never knew about.

kartgreen 02-03-2013 12:10 PM

Found this on another site a while back and it seems to work as well ,
Oxalic acid found in wood bleach( Lowes/Home Depot & paint stores
or Bar Keepers Friend , found in grocery stores in the cleaning products isle .A mixture of oxalic acid and water in a container to soak your rusty chrome parts .
Actually does a very nice job .
You can also seal chrome parts using sodium silicate ( Water Glass ) . Used to be able to find this at drug stores but lots of places to buy on-line .

Spokes 02-03-2013 02:08 PM

Another great rust remover is citric acid, which you can buy in pound qty's on-line. To put rust removal in perspective, acids remove rust. Acid types (Oxalic, Citric, Nitric, Phosphoric and the like) will be more or less aggressive. Heat activates chemistry, so acid strengh, type, temp. and exposure duration determines how aggressive rust removal will be. The latest craze is a neutralized acid such as Evapo-Rust and Metal Rescue have hit the consumer market. We use heated neutralized acid to remove rust at the plant (aerospace needle bearings) to remove occasional rust issues here in southeastern GA where the humidity is high.

The most delicate item for my projects is to save a gas tank. When you have no metal to spare then a neutralized acid is the way to go. I use a chrome cleaner from the auto store that has oxalic/phosphoric/nitric blend (super weak) that takes care of my heavy rust removal needs on robust parts.

Of course we are talking steel...cleaning aluminum is a whole different story. I have to say that the neutralized acid (Evapo Rust or Metal Rescue) will not harm aluminum. So when I get a nasty carb with metal choke arms or cooroded fittings, the neutralized acids work well.

Oh, by the way. The Crock Pot makes a great heated bath for derusting parts...since the wife never uses it...and Coke, Pepsi, Mountain Dew, Orange Juice works too!

JoeM 02-04-2013 07:01 AM

You should post your recipes! Citric acid / water ratios. temperature levels, cooking time, etc.

That's a cook book I would use :D

Spokes 02-05-2013 04:32 PM

Thanks, I would except whole careers have been formed around chemical engineering.

The best way to remove rust is a warm bath of a neutralized acid like the Evapo Rust or Metal Rescue. For larger projects phosphoric acid works well. I use chrome cleaner with phosphoric/oxylic/nitric blend, look on the automotive supply shelf and read the labels, you will find them.

Always use PPE and be aware that fumes often result with the reaction of oxides (rust) and acids. Fresh air, safety glasses, rubber gloves is the rule and keep a box or solution of baking soda to neutralize any spills. Keep pets away from all chemical work as well as childern. Always clean up. Never leave a chemical mess.

JoeM 02-05-2013 05:48 PM

My first love in high school was chemistry. Was going to go that route until I encountered computer programming, when it was more of a cult than a career.

My girlfriend went on to do her degree in chemistry and masters in ChemEng. I did love messing about in her labs, but seeing the amount of calculus she had to do, I was happy to stick to my COBOL... ha ha... :D

Spokes 02-05-2013 06:27 PM

I'm just a rouge science type with 41 years experience. Always practical applications of science to manufacturing. One of the few left who began working in the sciences before finishing college. It was a different world 41 years ago. I'm just a dinosaur now.


All times are GMT -8. The time now is 09:28 AM.

Powered by vBulletin® Version 3.7.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.