The acid test.

[Anonymous]

Hello,

I am currently having a go at rust removal using a bottle of Harpic Limescale remover. Harpic seemed a reasonably cheap and easily available source of hydrochloric acid.

I am curious to see A) if it removes rust and B) if it has any effect on 'sharpening' an old file. I have heard that you can send files away somewhere to be sharpened--they do it using acid. So I will be very happy if it has a noticeable sharpening effect.

The procedure is to basically leave the rusty items submerged over-night in a tub of the stuff and see what they look like in the morning.

I'll let you know how I get on.

PRECAUTIONS:
Don't leave the tub anywhere where children/pets can play with it.
Don't leave it in an unventilated room.
Wash your hands afterwards. Or better still wear gloves and a 3M mask.
Don't mix the stuff with bleach. No really.

Before picture. Some rusty tools.

 

[Anonymous]

I went and had a look at them after two hours. I decided to brush off some of the gunk with a brass brush so the acid could get to work on the gunk underneath the gunk. They looked pretty good. The above picture doesn't show how rusty these things were.

After another hour I noticed that they all started turning a bronzey/coppery colour. So I took them out and washed them thoroughly. Leaving them over night would have been too long, I think. I put them in the oven, on a very low heat to bake any remaining moisture off them (if I left them to dry normally I thought rust might start forming again.)

They certainly look better. The two files 'feel' sharper. I can't work out where the strange colouration has come from.

Here is a pic of them dried off and ready for the oven, no other cleaning has been done to them.

More to follow.

 

[Anonymous]

John

looks like electrolysis - possibly you have started to plate them in copper

 

[Shady]

Phosphoric acid is an excellent rust remover that won't give you funny effects: buy it as 'jenolite', and it'll remove any rust you can find if you give it the overnight treatment... (get the liquid, not a gel).

Just be aware that it'll leave a matt grey finish, which you will have to buff/wet or dry/wire wool out if you want a gleaming finish..

 

[Anonymous]

John

looks like electrolysis - possibly you have started to plate them in copper

Yes, that's what it looked like. The chemistry of it is beyond me. I was just looking for a cheap way of getting rid of rust. There was a tiny bit of copper that went into the tub (it was a springy bit on the measuring gauge--it was so rusted that it wouldn't come apart and I didn't notice there was a copper part to it, so I just put the whole thing into the tub) so perhaps that was how the copper was introduced?

The copper coating came off with a gentle scrub with wire wool. The measuring gague came up blindingly shiny! I was all set to chuck it out but I am very pleased it has come up so nice. The bits have come up rust free too. One of them has revealed itself to be a made in USA Irwin.

I'll examine the files tomorrow.

I am sure Jenolite works well. But a very quick search on the net shows it to be £9 for half a litre. Harpic is £1 for 750ml! You could probably get Jenolite, or some other rust cleaner cheaper. But I was looking for a real bargain-basement solution!

So far I would call this experiment 'interesting' and, at least as far as the measuring gauge goes, a success.

 

[Philly]

JG
Very interesting! I'll file this one away for future reference.
Cheers
Philly

 

[Waka]

JG

They have really come up well, a very good result from an experiment.

Now where's my rusty tool gone :-k

 

[Anonymous]

Lastly a look at the files. They have come out a little copper coated, which is odd, but I don't think it will adversely effect them. (Any copper should come off pretty quickly during use.) They are certainly cleaner and rust free. Pretty much all the gunk has has gone from the teeth. So they work a lot better. Are they actually sharper? I don't think so. Not really. But the absence of gunk in the teeth makes them feel a good bit sharper. They certainly have been given a new lease of life.

So the Harpic limescale remover is a pretty good product to use if you want to easily and cheaply (I used about 30 pence worth) remove rust from extremely rusty tools. The brush I gave them with wire wool was really just for cosmetic purposes and was just a 2 minute rub or less on each tool. It is good for spanners, pliers and bits etc. I wouldn't use it on anything really valuable or valued. Certainly not on anything collectable. But as a last resort 'either-this-works-or-it-is-going-in-the bin' type solution I would say it was pretty good.

The copper coating can be explained, I guess, by the presence of some copper in the mix. That's something to look out for. But I think it hasn't really hurt anything.

I am kind of tempted to use an old Record spokeshave (which has lost all its paint) and copper coat it--using my patent new technique, just for the look of the thing! A copper coated spokeshave would be a unique collectors item! Maybe there's a market for them on ebay?!

Here's a pic of the file, with a close-up of the teeth.