Should I apply the chemical that deactivates rust?

[billybobjoebob]

There is rust on my Gm17 filter and I'm worried it will eventually eat through. Should I use the chemical to stop it's deterioration

[JMB1943]

BBJB,

Given the nature of the item bearing the rust, I would tread very lightly!

You do need to remove active rust, so apply a light oil to the affected areas and let sit 2-3 days; this should help to soften the rust.

Start with 1) soft toothbrush, then 2) wooden toothpick, then 3) bronze wool ultra-fine, all with more light oil.

Bronze wool is not hard enough to scratch iron/steel.

I hope that others chime in, because I would like to hear other options.

You may hear about vinegar solution or citric acid solution etc, but which chemical do you have in mind?

Regards,

JMB

[Spaceman]

I would start by rubbing off the loose rust using brass wool or a small brass brush. In my experience, the best way to remove the remaining pitted rust on this sort of item would be to use Kurust Remover Gel not to be confused with the Kurust Rust Converter product. Once all the rust has been removed, the issue will then be how to protect the bare metal from going rusty again with the normal choice being between a layer of oil, wax, paint or lacquer. If it was me, as well as keeping the item in a dry atmosphere, I would probably start by trying a thin layer of wax or oil and see how that went.

Edited 15 September by Spaceman

[billybobjoebob]

On 15/09/2024 at 00:12, Spaceman said:

I would start by rubbing off the loose rust using brass wool or a small brass brush. In my experience, the best way to remove the remaining pitted rust on this sort of item would be to use Kurust Remover Gel not to be confused with the Kurust Rust Converter product. Once all the rust has been removed, the issue will then be how to protect the bare metal from going rusty again with the normal choice being between a layer of oil, wax, paint or lacquer. If it was me, as well as keeping the item in a dry atmosphere, I would probably start by trying a thin layer of wax or oil and see how that went.

I cleaned the rust mostly off and applied clp to keep the rust at bay. As I was informed by a long time collector/ friend of mine 

[Chasemuseum]

Appropriate action. If you had left the active rust to continue it would have started pin holing the sheet steel in a few years (may already have occurred) and ultimately left it as feeble rusty metal ready to collapse. So many British SBR canisters are already in this condition its horrifying. Its the difference between years of survival and decades of survival.

[Flavio]

Hi, I'll chime in too since sometimes in our collection made up of 75% pieces found in the field, there are also pieces recovered from attics which however obviously always require conservative interventions

When we are faced, as in this case, with an object that has traces of rust but also of its original colour, my son and I never intervene with operations that imply the use of abrasive wool (usually we use 000 grit as abrasive wool). the one for polishing furniture), but rather we use a small brush with naturally diluted oxalic acid after having made sure to protect every part that is not metal, in this case I would have masked and protected everything that was above the filter , from the fitting upwards

Once the acid has been left to act (naturally diluted with an appropriate concentration and left to act, checking the result as time passes), we clean with an old moistened toothbrush and the rust is completely removed, especially on such a smooth surface. Then once clean and dry I brush on a solution of microcrystalline wax for restorers diluted with a little white spirit, dry with a hairdryer or heat gun at low temperature and finally rub with a soft cloth and the result is guaranteed. Pure citric acid can make an alternative but nothing is as effective as oxalic acid. I hope I have been of help. Finally, congratulations for the Gummimask, which is difficult to find even in the attic, especially because the rubberized canvas tends to crack and get cut over time

Sorry, I'm correcting part of my post, not having seen that you had unscrewed the filter, I have a gummimask which is in difficult condition due to the canvas being ruined by time, so I couldn't have done it. So with the filter detached it is obviously easier and quicker. However, I see that the rust has partly remained, that type of rust is quite easy to remove with oxalic acid if you want to test it for example on the frame of the lower edge if necessary, you can also apply it with a cotton swab, the oxalic acid will you can find it on websites that sell materials for restorers who use it a lot on metal objects. 

Edited Tuesday at 06:33 by Flavio

[JMB1943]

Flavio,

Thanks for posting your advice for a piece as delicate and valuable as this one.

All of my clean-up experience has been with heavy duty steel (bayonets, helmet etc) and my advice was biased on that account, but I shall have to try the chelation method. 

I know that the paint would be vulnerable, but would fine brass/bronze wool be expected to scratch the metal of that gas-mask canister?

Regards,

JMB

 

 

 

 

 

 

[Flavio]

Let's say it might not ruin it, but I assure you that oxalic acid is deadly. Usually on things that have color or traces of color I always use oxalic, then if necessary as you say a bit of fine grain wool As for bayonets or similar, if they are very rusty we move on to the electrolysis process

[Flavio]

Here is an example of oxalic acid use... Italian multipurpose mask containers and Italian anti-glare lenses colored white for Alpine troops