Protecting Brass and Copper rivets from tarnishing

[SilverForgeStudio]

I have searched the archive and potentially am not hitting on the right combination of word or the right wording/phrase- so if this has been covered please let me know and what the proper keywords are and Ill go digging.

Trying to find out if I use brass or copper rod for rivets how to protect the leather from growing a verdigris/tarnish ring from forming.

Figured I would be able to paint the head and shank of the rivet with a bit of clear lacquer or nail polish- or even a disc of light plastic under the head like a washer to isolate the contact?

I have a few ideas I am trying and know I do not need to re-invent the wheel- but I have several pieces I tossed in a box and they all have whitish and green halos around them. And yes it is partly from non use/oiling/polishing or handling...

So Im hoping to avoid it on future projects or at least mitigate it in the meantime!

[mikesc]

Short term solution...nail varnish ( which is low grade acrylic lacquer ) ..chips very easily..and is not truly glossy ..because it is hygroscopic.

Long term solution.. 2 part ( 2 pack ) polyester or epoxy "clear" as used in "clear coats" for high grade metallic car paints..includes catalytic hardeners, cyanoacrylates* ( polyisocyanates ) usually..must use a mask ( against toxic vapours ) ..good to stay glossy for around 10 years ..

*Miss-use of them can kill you..overdose is odourless ..by the time you smell it, it is frequently too late..even the best masks give no warning when they are saturated and no longer filtering the toxins..and they are long term carcinogenic..

I came close to not waking up again twice when I was a custom painter using these..so i quit..

[fredk]

Rustins makes a metal lacquer which is robust and long lasting and is inexpensive.

[SilverForgeStudio]

Thanks Mike and Fred!

I dont think I will be using anything that volatile Mike! Sounds harsh- glad you are still among the living for it... sage advice. 

Fred I think Im on the right track with the lacquer route so thanks for confirming it- I appreciate the input folks- pics when the project is done!

[fredk]

linky; https://www.rustins.ltd/rustins/our-products/renovators-for-metal/ metal-laquer 

Rustins is designed for lacquering brass door furniture so it does last. I used to use it as a barrier between metals and metals-materials

[mikesc]

Yep, I think Fred's idea is safer ( you can't get it here though, unless ordered "online" ) ..nickel plated rivets ( or even gold plated rivets if you are going "luxury" ) is another option, I presume you'd know how to electro plate your own ..Just don't breath the chemicals or the vapours given off either :)

Edited to add..
Possibly a drop of clear epoxy , the kind sold for "incrustations/ inclusions" might work, epoxy should "hold on" to polished metal OK ( "ish" , test it ) and may not discolour ( again test it to see )..Polyester resin would no be clear enough, but some epoxies might be ?

Edited April 30, 2019 by mikesc

[SilverForgeStudio]

Thanks Fred and Mike- Ive gotten a small tin of "Brass Lac" from the overpriced art store/hobby shop near me- Ill give it a swing and see what happens! 

 

[z33]

I am new and have been reading a lot on brass and leather and pH and verdigris. I make leather belts, and while brass and brown leather look beautiful, I feel time will not be kind. I have already make the mistake of using neatsfoot oil on my leather. I am now given to understand that neatsfoot is acidic, and so I theorize it may promote corrosion of brass? I do not know.

I have read about benzotriazole, which is soluble in alcohol and warm water. I am wondering if micro spot treating just around the brass where it touches the leather is a good idea. 

I have also read about L-cysteine in PEG400 which is used to preserve wood/brass. I am wondering if n-acetyl-cysteine dissolved in water could be used to micro-treat the leather-brass interface; the water will dry, leaving the cysteine behind. I have no clue if it will be effective. I am also wondering if a borax solution can similarly be used very carefully;  leather has a usual pH of 3 to 5 and borax is alkaline and can dry out leather - but would minute quantities just at the metal-leather interface protect the brass?

[fredk]

I reckon you are over worried.

The ancients never worried about such thinks and in the UK leather items with brass items attached from up to 2000 years and more ago have been found. The brass is not corroded where it is attached to leather and if the leather is intact and still existant it shows no reaction to the brass item.

Are you wanting your items to last 2 millennia or more?

I think there is a lot of odd information flowing about on the internet. A lot of it is urban-myth. The people propagating this information have never actually experienced what they claim.

I've used brass buckles and loops and rivets with both veg tan and chrome tan leathers for over 20 years and never once have I seen any of these reactions which are claimed by internet worryors

[mikesc]

Benzotriazole, is going to be better than either n-acetyl-cysteine or borax... if you have it to hand.

Although they will all work..( as antioxidants ) in descending order of efficacy..
Benzotriazole ,
n-acetyl-cysteine*,
Borax** ..

However it, Benzotriazole does have some antiestrogenic properties, so on belts, yes..

But not on things that would be in long term skin contact such as watch straps , bracelets etc.

*n-acetyl-cysteine binds very well to proteins, such as the collagen in leather..but some people may show allergic symptoms on contact with items treated, fewer than the small percentage of those who show allergic symptoms after inhalation or ingestion, but..someone might decide to sue..

Various research and information about the collagen in leather can be found by searching that phrase "collagen in leather" ..without the quotes.

**Borax acts as a "pH buffer"..would have been better to apply it prior to posing the brass ware..and it may show up as micro crystals on the surface where it is applied after a time.

HTH :)

3 to 5 is quite a large range ( before neatsfoot oil..and neatsfoot oil covers "a multitude of sins" )..find out ( as far as possible ) which final pH which you are dealing with, before attempting to deal with it, and it's potential*** reaction with your metal ware.

***unavoidable ( well I could have, but decided not to ) pun ;)

Edited September 30, 2019 by mikesc