How To Get Rust Off Screws

If you need to undo a rusted bolt or screw, you may want to try removing the rust first. Here are a few clever ways to clean a rusty fastener so it can be unscrewed – even bolts with no heads and bathroom fasteners like toilet bolts.

Why do old metal fasteners get rusty?

Nuts, bolts and screws can get rusty because of corrosion, a natural reaction that occurs over time between some metals and their environment. Some fastener materials and finishes are prone to rusting. For example self colour steel rusts fast, but stainless steel takes much longer. Mixing different metals together can also cause reactions.

Metal fasteners will also go rusty faster if they're outside, underwater, or in damp environments like bathrooms.

3 ways to clean rusty nuts, bolts and screws

If the rust is superficial, you may be able to clean a rusty fastener in order to remove it - here are a few methods:

Rust remover products – Do exactly what they say on the can. Simply spray over the head of the screw or bolt, making sure the threading gets covered too. Once it's been left for a bit, the product should break the bond that's formed between the screw and its interior threading. You can then try to remove the fastener.

Plain old WD-40 – It won't be as fast as a specialist product for removing rust from screws, but it may do the job. It helps by loosening the rust-to-metal bond and may help you to clean and undo a rusted bolt or nut.

Make your own spray – Try a half-and-half mixture of acetone and transmission fluid. If you don't have those, hydrogen peroxide, lemon juice, white vinegar, baking soda and even cola are all good at dissolving rust.

If you've used something like cola to clean your rust, give your fasteners an extra clean afterwards.

Once you've cleaned your bolts or screws of rust, consider whether the fastener is worth keeping. Old screws with corrosion damage aren't as sturdy, making them a safety risk if you're using them for something important.

Using screws for an outdoor project? Here are our best outdoor screws , with extra protection from rust.

Other ways to loosen a rusted bolt or screw

Sometimes, if you want to undo and remove them, cleaning rusty screws and bolts isn't enough. Your old rusted fasteners might need a visit from the hammer and blowtorch. If you need to free a bolt fast, try these:

Hammer It – A short, sharp tap to a rusted screw or bolt can help break the rust bond that's keeping it stuck. Use a hammer after you've added a rust removing spray for extra boost, and always wear eye protection.

Heat It – Using a torch at low or moderate heat can help rusted fasteners to expand, allowing them to be unscrewed. If you've been trying out flammable lubricants, be very careful not to ignite any by accident.

Cut It – If all else fails, you may need to cut the screw or bolt out. This could include cutting around it, through it entirely, or cutting a new slot in the head for leverage. Doing this may leave your fastener unusable.

How do I remove a rusted bolt with no head?

If your rusted bolt is now broken and wedged in a hole, don't give up. Try to cut a slot in the top of the bolt thread, if you can, and twist it out with a slotted screwdriver . Make sure you've drenched it in rust removing fluid and that it's seeped into the threads. Some have luck welding another bolt on top, but never do both at once (flammable).

Can I prevent bolts from rusting in the first place?

If you don't want to spend time cleaning rust off nuts, bolts and screws, choose fasteners with some corrosion resistance. Choosing high-grade stainless steel or even plastic fasteners can help protect them from rust.

For damp or underwater applications, such as toilet bolts, look out for materials with extra resistance.

You can prevent rust by adding a layer of protection to your screws. Rustproofing methods can include specialised rust sprays, wax-based aftermarket kits, and buying screws that have been galvanised with a corrosion-resistant layer. Read our blog on fastener materials and finishes for more information on which are best at preventing rust.

Certain environments and treatments will also cause screws and bolts to rust quicker, such as:

- Atmospheric pollution, such as acid rain if your fasteners are outside

- Exposure to salt water, which is more corrosive than normal rainwater

- "Rust traps", where fasteners are in places than attract or gather water

Got any more questions about removing or cleaning a rusty screw, nut or bolt? Contact us for our expert advice.