Jump to content

Recommended Posts

Hello,

I got some really old Dumont tweezers. They had a little rust on them (only thin rust on surface). I decided to polish them with  fine sandpaper (1000) and get rid of the rust. Everything was fine, however, after a week of no usage, I noticed new surface rust, and the rust was exactly where the finger prints were left. 

Did I actually destroyed some kind of protective film on steel? Is it possible to get rid of the new formed rust and protect the tweezers from obtaining rust on their surface?

 

Thanks.

Share this post


Link to post
Share on other sites

There is no film on them. At least i don't think so.  Maybe you can oil them slightly and then wipe it of. But that you need to do very time you use them.  It's probably carbon steel tweezers you have? 

Share this post


Link to post
Share on other sites

I am not sure, but these are really old tweezers, maybe 30 years old. They have INOX mark and are incredibly pleasant to work with. That is the reason I switched to them, instead of my old cheap tweezers. However, I was little disappointed when I saw the rust on them.

Share this post


Link to post
Share on other sites
7 minutes ago, bojan1990 said:

I am not sure, but these are really old tweezers, maybe 30 years old. They have INOX mark and are incredibly pleasant to work with. That is the reason I switched to them, instead of my old cheap tweezers. However, I was little disappointed when I saw the rust on them.

They should stand up to the rust better then the Carbon steel. Have some Inox but never seen any rust on them. ya they are black but no rust. Maybe try some vinager to remove the old rust. 

Share this post


Link to post
Share on other sites

Any idea how to protect them? The rust itself is not a huge problem (it appears only on spots which are in direct contact with my hands) but nevertheless I would like to get rid of it. It is interesting that the tweezers that did not have any rust on them, and which I did not polish still do not have any rust on them. That lead me to believe that I removed some kind of protective coat on them. I will try to polish them again, put little oil and wipe them a little. Maybe that would help.

Share this post


Link to post
Share on other sites

INOX is essentially Stainless Steel so shouldn't rust although my SS exhaust has

 

I've read a while back of someone masking off the inside surfaces then applying a layer of car gloss to give a bit of protection.

 

 

Share this post


Link to post
Share on other sites

Contrary to popular belief, most stainless steels are not impervious to some amount of rusting. Your tweezers most certainly DID have a coating on them in the form of what is known as passivation.  In sanding them, you have removed that protective layer of oxide built up over many years, exposing them to the acids in your skin. 

Share this post


Link to post
Share on other sites

That is what I was afraid of. Because the other pair of tweezers I did not polish (because it did not have rust) did not developed rust after working with. These pairs that I polished developed rust along the finger prints I left on them.

I polished them again and put little oil on them. Waiting to see what happens and I get rust again.

Share this post


Link to post
Share on other sites

There are rust convertors in auto shops which convert the rust to a stable ferrous compound but often the result is the old rust is turned black.   Most decent quality diesel/petrol engine oils have a high level of metal passifiers (iron, copper aluminium etc) to protect the various engine parts.  You could try soaking the tweezers in some engine oil (maybe warm it up a bit) for a couple of days.  Should then be able to wipe clean with a bit of lighter fuel/IPA to remove oil residue. Watch oils and the like will have passifiers but the levels are unlikely to be as high as an engine oil.  You could follow up with a polish with furniture wax which would leave a very thin extra seal, especially in the rust micro-pitting.  Cheap and cheerful so worth a try maybe!

Share this post


Link to post
Share on other sites

I suggest mirror polishing them and then cleaning well with acetone. Finally, seal with either spray on clear coat or do what we do on cast iron wood working machine beds- car wax. You can’t run exotic wood over an oily slab of iron...

roughening them with 1000 grit opens up the surface to more oxidation. There are also ways to accelerate the passivation that I don’t know, but I’m sure google knows. Probably heat, humidity and an acid like lemon juice. 

Share this post


Link to post
Share on other sites

Stainless cases are typically 316 stainless which is resistant to many chemicals. It can “haze” after a few decades but literally a wipe with sunshine cloth and it’s right back again. 

Some “base metal” cases are brass (of unknown grade) plated with chromium. You can generally tell these as the back is slightly grayer than the Case, as pure chrome is whiter than 316. Backs are pretty much always 316 on “stainless back” watches. 

I don’t like chrome plated cases since you can’t do anything with them. Any work and the plating is gone. Replating is an option if you have a source for it. I just avoid them other than as parts donors. 

Share this post


Link to post
Share on other sites

So far, I do not have problem with corrosion on tweezers. As I said, I polished them with sandpaper 1000, put little oil on them (some oil I use for my bicycle) and remove the excess oil with soft cloth. We will see if that helps on long run.

Btw, my hands sweat like a hell. 

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×