Thread: How much citric acid?

Originally Posted by Waldo

How much citric acid do I use to clean a plane and at what ratio to water?

I pour the whole small container into a tub (roughly 560mm x 390mm and 130mm deep) and fill it almost to the top with cold water. You only asked about the ratio, but just be really careful with this stuff, 'cause it could eat away your plane. It was trial and error for me, just testing how much to use starting with half a container at first. Hot water works way faster than cold. I did a test with once with hot water and it ate through the iron piece.

I remove as much rust as possible before I put it into the bath and check the progress at around 30 mins. I tend not to leave plane bodies in there for more than 30-40 mins. If you see pin prick holes, it's too late, take it out immediately. When the metal is cleaned and dried, it'll still rust so I apply some rust inhibitor followed by some oil to neutralise it. I reuse the bath till the water starts going off. If I was game, I'd prefer to use the electrolysis method and not worry about the acid eating away the plane.

Originally Posted by mkat

If I was game, I'd prefer to use the electrolysis method and not worry about the acid eating away the plane.

Me I prefer the Molasses method.

Yes it takes 10+ days, but it is safer than acid, and easier than electrolysis especially with smaller parts.

Robert34

Hey.

I just have a large container with about 4 parts water to one part lemon juice. I chucked a few teaspoons of citric acid in there the other week to help it along. I soak rusty stuff for around 12-15 hours, and then whip it out and scrub it down with steel wool. Seems to work fine ... haven't destroyed anything yet. If it's still rusty, stick it back in for a bit more. Rough science, but it works for me.

GW

I've used vinegar, with good results. Only the best brands, 'No Frills' I beleive. Leave it overnight in enough vinegar to cover the plane body and bits.

Personally I find electrolysis the preferred method, more fun too. One feels like a mad Scientist.

In AWR (I think issue 40) they reccomend 5% citric acid solution, followed by agitation in 1% washing soda (Lectric Soda brand) to neutralise any acid.

Originally Posted by Robert34

Me I prefer the Molasses method.

Hi Robert,

How well does it clean?

Hi Robert,

Just to help clarify, the citric acid is safe. You can use Kool-Aid if bulk citric acid is difficult to find. In fact, any citrus flavord powder mix can be used as citric acid is the main ingrdient.

Used as a preservitive in hot dogs and sausage. And bunches of other food products.

Does sting a bit if you have an open cut, but that's about it. As mentioned, vinegar can also be used.

Both are less expensive than molasses. Don't taste as good, though!

Take care, Mike

Citric acid is very easy to find here, all supermarkets have it in the spices/baking section, I guess it's a hangover from English-type desert cookery. Kool-Aid on the other hand, one would have to make a trip to www.usafoods.com.au

Originally Posted by MikeW

You can use Kool-Aid if bulk citric acid is difficult to find. In fact, any citrus flavord powder mix can be used as citric acid is the main ingrdient.

Hi Mike,

I've been buying the small containers of citric acid 'cause I can't find it in larger quantities, so thanks for passing that on.

I've also heard that vinegar does a decent job. I use kero with a scourer and steel wool on metal where surface rust is prevalent.

You can use vinegar, but Citric acid is supposedly better.

From the article I mentioned earlier...

"Citric acid and oxalic acid work particularly well because they are chelating (binding) agents as well as acids, so they bind tightly to the ferric and ferrrous ions."

and on the subject of molasses...

"It can also cause an unattractive etched surface and therefore may not be suitable for hand tools"

I've never used the molasses method, so meh, take it with a grain of salt.

EDIT: Italics mine.

I've just used an approximately 10% solution. That is, 10g powdered citric acrid to 100ml of water. Works a treat in just a couple of hours.

As noted above, you can buy the powdered citric acid from the spices section in the supermarket.

G'day,

Thanks for all the help fellas, and thanks markharrison for the ratio. I got caught up in aother things in the shed today so I didn't get around to the plane. I'll give it a go tomorrow all going well.

Originally Posted by mkat

If I was game, I'd prefer to use the electrolysis method and not worry about the acid eating away the plane.

G'day Michael,
electrolysis is dead easy. I've now used it on 3 rehabs. I've 'done' all the small metal bits right down to the steel screw that holds the screw adjustment plate on.
The citric acid is bad news if you leave stuff in too long.:eek: Electrolysis only removes rust. I lreave mine in overnight if its big stuff...no probs.
Cheers

I found this article on the fine tools website that derekcohen mentioned.
http://www.wkfinetools.com/restoration/removeRust/

Gives a great pictorial on using citric acid for cleaning tools.