Yeti Rambler Cups and bottles are vacuum insulated and can keep ice cold for 24+ hours and keep drinks hot for 12+ hours. They are durable and made from kitchen-grade stainless steel.
But we all know metal has a tendency to rust over time, especially when exposed to water. So do Yeti cups and bottles rust?
Yeti Rambler cups and bottles are made from 18/8 stainless steel which, while rust-resistant, can actually rust. Luckily the rust is fairly easy to clean so you can get your Yeti back to looking as expensive as it cost you.
You may also want to know that if your Yeti does happen to rust what causes this. Is your product defective, is this normal and of course…how can you get rid of this rust.
I'll explain all those things in today's article.
What Make a Yeti Cup Rust Resistant?
Yeti Rambler cups and bottles are made from kitchen-grade stainless steel. A similar grade of stainless steel to what your kitchen sink might be made out of.
So what is it about this type of metal and Yetis in particular that make them rust resistant? Is there something special about them?
The reason is…science!
Yeti cups and bottles are made from what's called 18/8 stainless steel (also called 304 stainless steel. The 18/8 stands for 18% chromium and 8% nickel.
It is the chromium in the stainless steel that makes it rust resistant.
Say Yeti cups were made out of pure steel with no chromium. Once exposed to water/air the iron in the steel would react and create ferric oxide (also known as iron oxide or rust).
However, instead of reacting with the iron the water/air reacts with the chromium and forms chromium oxide. This forms a thin protective layer over the stainless steel which doesn't easily come off.
This then protects the underneath iron from being exposed to air or water and therefore stops it rusting.
Yeti coolers are not magic and there is no plastic layer or varnish on the inside protecting them from rust. It is simply the chromium in the stainless steel that makes it unlikely to rust.
As long as there is over 12% of chromium your Yeti is going to be rust resistant and highly unlikely to rust. Given the percentage sits at 18% you shouldn't have any major problems with rust.
Can A Yeti Cup Rust? How Likely Is It?
Yeti cups and bottles are rust resistant and they are highly unlikely to rust from just day-to-day use. But it is definitely possible for them to rust, either through bad luck, old age or exposure to corrosive chemicals.
This reddit post show a perfect example of little spots of rust that are occurring inside a Yeti cup.
There are also customers on twitter complaining about rust in a Yeti Tumbler that is only 3 months old and that has only been hand washed.
Given how many millions of Yeti Rambler cups, tumblers and bottles that have been sold over the years and how few references to rust there are online, I would say it's highly unlikely for a Yeti cup to rust. However, it is possible.
What Causes a Yeti Cup to Rust?
There are a few different things that can cause your Yeti cup to rust.
Chemicals Like Bleach and Chlorine
Chlorine is one of the few substances that reacts poorly with stainless steel. It strips it's protective layer and then corrodes the metal underneath.
Regular chlorine based bleach can cause stainless steel to corrode and rust fairly quickly.
Salt Water Exposure
Salt water is more corrosive to metals than regular water. It's highly unlikely you'll have salt water in your Yeti cup or bottle on a regular basis but if you live near the ocean and leave your Yeti outside this could cause some rusting.
Extremely High Temperatures
The 18/8 stainless steel that Yetis are made from can withstand really high heats. It can handle heats up to about 750-1550°F (400-850°C) without any issues.
But once it gets up to and above these temperatures it can cause the surface of the stainless steel to no longer have enough chromium to protect the cups and bottles from rusting.
It's extremely unlikely you're going to get your Yeti up to temperatures even close to that so you don't need to worry about this.
How To Prevent Rust in a Yeti Cup
Preventing rust in your Yeti cup is pretty simple. You just want to keep it away from corrosive liquids like bleach or salt water.
You also want to make sure that you're cleaning it and leaving it to dry on a regular basis. You don't want lots of excess moisture trapped in your cup for long periods of time allowing mold and other bacteria to grow. Click here to learn how to clean a Yeti cup properly.
You may also want to avoid super acidic liquids like lemon juice as this could potentially cause corrosion. Coffee is actually not very acidic so should be fine.
How To Remove Rust From a Yeti Rambler Cup
Maybe you've accidentally exposed your Yeti to a corrosive liquid or your mum has gone ahead and soaked it in bleach because that's what they did in her day.
Maybe you've just been unlucky. If you've got rust in your Yeti how do you clean the rust from a Yeti cup or bottle?
What NOT To Do
There are some things you want to make sure you don't do in order to try and clean the rust off your Yeti as this can cause other issues.
The first big one is – don't use bleach!
Bleach will cause most rust and corrosion to your Yeti.
While steel wool is generally fine for the inside of your Yeti don't use it on the outside as it will scratch off the powder coated paint.
Also make sure you give it a good rinse afterwards as if any bits of the steel wool flake off an stay in your Yeti then these can rust and cause rust stains in your Yeti.
How Should You Clean Rust From a Yeti Cup or Bottle?
There are a few different strategies you can use to clean rust from your Yeti cup or bottle.
Use a Magic Eraser
Magic erasers are micro-abrasive and great for polishing away surface rust. They are made from a type of plastic foam and are super easy and effective to use.
It also won't leave behind any flecks that can rust. Combine this with the Coca-cola method below for best results.
Coca-Cola is surprisingly good at helping to get rid of rust. It contains phosphoric acid which dissolves the rust making it easier to clean off.
You can then wipe most of it away using a bottle brush or for better results use steel wool or a magic eraser.
Phosphoric Acid Liquid or Gel
If you want to go to the extreme then you can buy phosphoric acid or gel that you can use to remove the rust.
You can get it from your local hardware store or you can get it from Amazon.
Using an abrasive cleaner like bicarb soda can help to remove the rust with a good scrub. Mix it with a little bit of water to make a paste and give your Yeti a good scrubbing.
Mix with vinegar as the acidic vinegar can also help.
Or get an abrasive sponge or bottle brush and use that to rub away the rust.
Fine Steel Wool
While I don’t personally recommend using steel wool if you don’t want to try anything else then you can use 0000 fine steel wool which will polish away the rust.
Just make sure you thoroughly clean your bottle afterward to remove any steel particles as these will likely cause future rust issues.
The good news is that once you’ve cleaned away the rust from your Hydro Flask the chromium should form a naturally protective layer and it shouldn’t just rust again.
If your Hydro Flask continues to rust even after you’ve remove old rust then there may be a manufacturing defect and you may need to contact the company and ask for a replacement.
Does The Yeti Rambler Warranty Cover Rust?
If you don't want to clean the rust from your Yeti cup or bottle or you've tried to clean the rust off without success you may be wondering does the Yeti Rambler warranty cover rust?
There is nothing on the Yeti Warranty page that specifically talks about rust. But some people have contacted Yeti with rust issues and shared their results.
No, the Yeti Rambler warranty does NOT cover damage by rust. Yeti advises using “Bar Keepers Friend” in order to remove stains and rust from your Yeti. However, if you still have rust after doing this they will replace it for you.
Someone tried to get their rusted Yeti cup replaced and they got this response from Yeti which they shared in this forum post:
YETI stainless products are rust-resistant, however, rusting can happen on occasion. If you’re experiencing rusting on your stainless product, we recommend using Bar Keepers Friend Cleanser & Polish. This should remove the rust/staining and maintain the life of your Rambler. Should your cup still have staining, feel free to send a follow up note and we can begin the warranty process.
The YETI Outfitters
So it seems like Yeti won't just automatically replace your Yeti if it has a bit of rust. However, if you've got serious rust issues that you haven't been able to fix then they should honor their warranty and replace it for you.