Rust vs tea, Round 1

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Kludge

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Somewhere in my very, very checkered past (and I still refuse to discuss parts of it no matter how drunk one gets me. ;D), I heard that the tannic acid in tea was enough to combat mild rust. Since I know tannic acid is used in some rust killers, the question came up in that highly convoluted space my mind should occupy if there's enough of it in tea to work or if what I'd been told was an urban myth, old machinists' joke or whatever.

Any thoughts?

Best regards,

Kludge ... who seems to come up with the strangest questions ... :D
 

Tin Falcon

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The tannin is the heart of a rust converter. It reacts with the iron oxide, converting it to iron tannate, a stable blue/black corrosion product. Tannins are a group of water- and alcohol-soluble natural products extracted from a variety of plants. Little is known about their true structure as they are complex and variable. Industrial research in the effectiveness of tannin solutions as rust primers began in the 1950s. Since then, tannic acid (a tannin) has become a standard conservation treatment for corroded iron artifacts found on archeological sites.
http://corrosion-doctors.org/MetalCoatings/rust-converter.htm
Did you try "tannic acid vs rust" in a google search ?
Tin
 
K

Kludge

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Tin Falcon said:
Did you try "tannic acid vs rust" in a google search ?
Yep, but no mention of tea. I know about the tannic acid connection but the question was more about whether or not the use of tea was adequate or if someone was pushing ... ummm ... pulling my leg.

BEst regards,

Kludge
 

CrewCab

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In all fairness I must subscribe to the school of "I think it's an Urban Myth" ........... let's be fair if "Tea" contained a corrosive acid there would be no Builders left in the UK ::)
CC
 

bentprop

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"I think it's an Urban Myth"
Well,better call the "Mythbusters" team then ;D
When you mention tea and acid,I once knew an old engineer who used to put a drop of sulphuric acid in his tea.He said it"gives it a bit of bite".Can't have done him much harm,'cause he lived to a ripe old age 8)
 
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Kludge

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CrewCab said:
In all fairness I must subscribe to the school of "I think it's an Urban Myth" ........... let's be fair if "Tea" contained a corrosive acid there would be no Builders left in the UK ::)
I tend to agree with the urban myth as well but I figured I'd ask anyway.

As to corrosive acid ... keep in mind that tannic acid is also used for tanning leather, hence the name. Due to constant exposure, this explains the stiff upper lip. :D

Best regards,

Kludge
 

Brian Rupnow

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Kludge--I can't speak for tea as a rust combatant, but being into hotrodding as a hobby, I belong to a couple of hotrod websites. Many people swear by the properties of molasses as a very good rust remover. It seems that it is mixed in a high concentration with tap water, and parts are left to soak in it for a few days. I have seen a few posts of before and after pictures of old auto artifacts treated with this method, and it does seem to do a rather amazing job.---Brian
 
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Kludge

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bentprop said:
"I think it's an Urban Myth"
Well,better call the "Mythbusters" team then ;D
They have a website so I may do that.

When you mention tea and acid,I once knew an old engineer who used to put a drop of sulphuric acid in his tea.He said it"gives it a bit of bite".Can't have done him much harm,'cause he lived to a ripe old age 8)
I wonder how that reacted with the hydrochloric acid that's a major component of gastric acid. I also wonder how he came about that odd combination. :D

BEst regards,

Kludge
 
K

Kludge

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Brian Rupnow said:
Many people swear by the properties of molasses as a very good rust remover. It seems that it is mixed in a high concentration with tap water, and parts are left to soak in it for a few days.
Thanks, Brian!

Hmmm ... I wonder if the sugars in the molasses combine with the oxygen in rust to create a mild etchant. There's a lot of oxygen available and plenty of hydrocarbons to combine with it, and the water would thin it and help it get in closer contact with the metal.

Okay, I have a few things I can experiment with so my next shopping tour will include some molasses.

Again, many thanks.

Best regards,

Kludge
 
K

Kludge

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Brian Rupnow said:
Kludge---I just did a quick web search on it--here is a link that describes the chemical reactions that take place.
Cool, thanks! I did a search on "chelation", which is the magic used, and apparently it binds to the rust and holds it in suspension. When the mollases is all full up and can't bind to any more rust, it can just go down the drain where commercial ones may have some issues with that form of disposal.

Since I have several things here that need attention to some degree or another, I'm going to try some experiments with a variety of commercial and home grown "rust remedies" (including tea ;D) to see what happens.

The only thing I've used tea for before aside from drinking and compresses, is dying model ship sails. Maybe I've got a new use. Thankfully, Red Rose is cheap.

BEst regards,

Kludge
 

Andrewinpopayan

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I believe the tannin used for tanning is extracted from the english oak tree, possibly from the acorns.
 

raym 11

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Possibly from a Tan Oak tree? (bark)

Ray M
 
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Kludge

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Andrewinpopayan said:
I believe the tannin used for tanning is extracted from the english oak tree, possibly from the acorns.
I know a few folks back on the mainland who may be able to help with that since there are no oaks here in Hawaii that I've found. Alternatively and with luck, I'll find someone who worked one of the old cattle ranches on the Big Island who'll know what they used instead.

The mention of tanning leather (aside from the occasional commentary about the English ;D) was incidental to the main line of questioning which concerned the existance of sufficient tannic acid in tea to combat rust, but now you've got me curious what the locals did back when cattle ranching was a profit making operation. ???

BEst regards,

Kludge
 

bentprop

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"I wonder how that reacted with the hydrochloric acid that's a major component of gastric acid."

Kludge,now that you've reminded me,I've come to the conclusion it probably was hydrochloric rather than sulphuric.

As for rust removal,does citric acid do anything to rust?We use it to clean the lime scale out of our electric jug,and it comes up really nice 'n shiny.I know muddle engin ears also use it to "pickle" a silver soldered boiler,or anything silver soldered for that matter.At least it's a darn sight safer than any of the more agressive acids.And it's cheap!
Regards.Hans.
 

Brian Rupnow

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I believe that American Indians used a mixture of brains and wood ashes to treat the animal skins that they wore as clothing. Not sure if that qualifies as "tanning" or not.
 

Tin Falcon

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Brian has been several years since reading researching tanning but the wood ashes were used to remove the fur from deer hide etc and the brains were used to preserve the leather. Yes it is considered tanning.
As a vet friend has said every animal has enough brains to tan its own hide.
Tin
 
K

Kludge

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Tin Falcon said:
As a vet friend has said every animal has enough brains to tan its own hide.
But it takes another "animal" to actually do it. Hmmm ... :)

Best regards,

Kludge
 
K

Kludge

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Okay, so an experiment is in order.

I went out and got some Naval Jelly, Extend (contains tannin), molasses and Coca-Cola (phosphoric acid like Naval Jelly). I already have tea so that's not a problem.

The base to the watchmaker's drill press will get the Naval Jelly. The throat plate for the Dremel will get the molasses. I have a couple jeweler's saw frames that will get the Coke. Since tannin blackens steel and requires a complete coating of rust to work (It'll actually cause unrusted steel to rust.) I'm not sure what I'll hit with the Extend and the tea but I'll find something even if I have to rust it ahead of time. :D

I have a few other items for the phosphoric acid & molasses treatments since they don't blacken the surface so I'll have plenty of stuff to lay with.

And, yes, there will be before and after photos to go with it.

Best regards,

Kludge
 

wareagle

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Very cool. I am very curious to see the results of this little experiment.
 
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