Citric acid test

[Jeff]

I can't debate the math but I'll still buy the Evapo-Rust. I don't have many rusty tools that need derusting and cleaning.

 

[sawman101]

I've got a whole tractor that I need to do that to--I need a really big bucket!

 

[Chris C]

I actually have one of those blue plastic kiddie pools beside my shop with 4 bourbon barrel rings soaking.... the wife is not amused.

 

[NOTW]

I actually have one of those blue plastic kiddie pools beside my shop with 4 bourbon barrel rings soaking.... the wife is not amused.

i know that feeling, apparently filling a 5 gallon bucket from the sprayer on the kitchen sink and then going on the front porch and unplugging the Christmas lights to plug in the battery charger for electrolysis is shunned upon...who knew.

 

[Gofor]

Chris: Did you use baking soda in the rinse water to passivate the acid, or was plain water rinsing enough to prevent flash rust?

 

[Chris C]

I used plain water. The was a little but not enough to get in a twist about. I just dried with a towel before I reassembled.

I did two #5 Stanleys a few days before that I had to paint and I didn't feel the need to do anything before I sprayed them. YMMV.

Chris: Did you use baking soda in the rinse water to passivate the acid, or was plain water rinsing enough to prevent flash rust?

 

[Camp Perry Skip]

We used to clean bilges with Citric Acid in the old Guard! Good stuff!

 

[Strom]

After reading this thread I Got some CA. Have an old pot I have used for outdoor cooking. Put it in CA and boiled it. It took off about 10 recent of the discoloration over night . It's still soaking. Have not tried it on rust yet. Too slow for me so far.

 

[Mike Davis]

After reading this thread I Got some CA. Have an old pot I have used for outdoor cooking. Put it in CA and boiled it. It took off about 10 recent of the discoloration over night . It's still soaking. Have not tried it on rust yet. Too slow for me so far.

The pot may have baked on grease which will not be cut by citric acid.
Try boiling water with Dawn or other strong detergent to cut the grease then CA again.

 

[Jeff]

Is your outdoor cooking pot cast iron? I clean my cast iron pots in a wood fire outside-heat them slowly and increase the heat until they're really hot. They can stand intense heat so don't be bashful with heating them really hot. Cool slowly and remove the scale with a wire brush. You shouldn't have much rust underneath that grease layer.

The pot may have baked on grease which will not be cut by citric acid.
Try boiling water with Dawn or other strong detergent to cut the grease then CA again.

 

[Mike Davis]

If you search any of the antique cast iron pages you will find complaints about people burning out old fry pans.
It its highly discouraged.

 

[23tony]

I know everyone goes bonkers if you mention using Vinegar, and that it supposedly continues to "Eat-away" at the metal... but how would it be different from the citric acid? Logic suggests that if one acid needs to be neutralized, all of them would be...

Vinegar may be stronger than the solution used here (or may not be), but I don't see much difference.

 

[Jeff]

Vinegar may be stronger than the solution used here (or may not be), but I don't see much difference.

Citric acid and acetic acid (vinegar) are both very water soluble so thorough rinsing in water removes them. Neutralization is not necessary with either one.

 

[Hmerkle]

Citric acid and acetic acid (vinegar) are both very water soluble so thorough rinsing in water removes them. Neutralization is not necessary with either one.

The claims I have seen are that some material (especially the vinegar) "goes deep" into the steel and continues to work on the metal... seems like BS, but is there any proof that this is not true?!

 

[Mike Davis]

The claims I have seen are that some material (especially the vinegar) "goes deep" into the steel and continues to work on the metal... seems like BS, but is there any proof that this is not true?!

Maybe in cast iron which is much more porous than steel?

 

[Hmerkle]

Maybe in cast iron which is much more porous than steel?

That is what I am thinking, but is that really true?
Is cast iron hygroscopic? (for example - nylon IS hygroscopic)
Definition: Defined: Hydrophilic, Hydrophobic, Oleophilic, Oleophobic & Hygroscopic

ANNND, if it is and a cast iron item that is soaked in vinegar, does it then require a baking soda rinse or soak?
Finally, will that work, since the nature of a titration is that the product is atomically "larger" than the solution (water in this case) in which it is disolved...

 

[Gotcha6]

As a side note and question, are you buying pure citric acid, or fruit pectin from the supermarket? I thought about the fruit pectin, or canning pectin, but when I looked at the label citric acid was only one of the ingredients. Would it do the same thing in a pinch?

 

[Chris C]

 

[sandfarm]

I use white vinegar for sharpening files. I just finished about 35-40 files. I changed vinegar three times doing that many. I usually try to leave files in vinegar for 24-48 hours. I have left files in vinegar for more than a week, I forgot about them.
The long time didn't do any harm.