Can You Weld Stainless Steel to Mild Steel with 7018?
Table of Contents
Introduction
When people work with metal projects, one common question is: Can you weld stainless steel to mild steel with 7018 rods? The short answer is yes, it’s possible, but it’s not as simple as just striking an arc and fusing the two together. In this article, we’re going to break down this topic in plain language, so even if you’re not a welding pro, you’ll understand the basics and what to watch out for.
What Are We Dealing With?
Before we get into welding, let’s talk about the two metals. Stainless steel is known for resisting rust and looking shiny for a long time. It’s often used in kitchens, cars, and outdoor equipment. Mild steel, on the other hand, is a softer type of steel. It’s cheaper and easier to work with, but it can rust if you don’t protect it.
When you try to weld these two together, the problem is that they don’t have the same chemical makeup. That means the weld joint can crack or corrode if you don’t handle it correctly.
What is 7018?
7018 is a type of welding rod people use with stick welding machines. It’s popular because it makes strong, clean welds on mild steel. But when you try to join stainless steel to mild steel, you’re mixing two different metals, and that’s where it gets tricky.
7018 can fuse the metals together, but it doesn’t give the best long-term protection against cracking or rust at the joint. There are special rods made for stainless steel, but if all you have is 7018, it can still work if you take precautions.
Can You Really Weld Stainless Steel to Mild Steel with 7018?
Yes, you can. The weld will hold if done correctly, but it may not be the best choice for jobs where the weld needs to last for years without maintenance. Here’s why:
- Different expansion rates: Stainless and mild steel expand differently when they heat and cool. This can put stress on the weld.
- Rust risk: The mild steel side of the weld is more likely to rust over time.
- Cracking: Without the right rod or technique, the joint can crack under pressure or over time.
If you’re doing a quick repair or a project that won’t be exposed to harsh weather, 7018 can do the job.
Tips for Welding Stainless to Mild Steel with 7018
If you want the weld to hold up, here are some easy-to-follow tips:
- Clean the metals well. Dirt, grease, and rust can weaken the weld. Use a wire brush or grinder to clean the area.
- Preheat the metal. Warming the steel a little before welding can reduce stress and help the weld flow better.
- Use small welds. Short weld passes help reduce heat build-up, which can cause cracking.
- Protect the weld afterward. Since the mild steel can rust, painting or coating the weld area is a good idea.
Where Would You Use This Kind of Weld?
You might need to join stainless and mild steel in home projects, auto repairs, or even DIY furniture. For example, you might have a stainless steel t section and need to attach it to a mild steel frame. Using 7018 rods can make it work if you take care with your technique.
Common Questions People Ask
1. Is steel waterproof?
This is a question many beginners have. Steel itself isn’t “waterproof.” Both stainless and mild steel can handle water, but mild steel will rust if it stays wet. Stainless steel resists rust better, but it’s not immune if it’s in salty or harsh environments. So, if you weld stainless to mild steel with 7018 and expose it to water, the mild steel side of the weld will still need protection to last.
2. Can you put magnets on stainless steel?
Yes, sometimes. It depends on the type of stainless steel. Some stainless steels are magnetic, while others are not. Mild steel is always magnetic, so after you weld the two together, you’ll probably be able to stick a magnet near the mild steel part. If your stainless steel t section is the magnetic type, the magnet might stick there too.
3. Will the weld be as strong as mild steel-to-mild steel?
Not exactly. The difference in metals can make the joint a bit weaker compared to welding the same type of steel together. But for many small projects, it’s still strong enough if done properly.
Protecting Your Weld
When you mix stainless and mild steel, the weld area is more vulnerable to rust. After you finish welding with 7018 rods, it’s smart to add a protective layer. You can:
- Paint over the weld
- Use a rust-resistant coating
- Keep the weld out of constant moisture
Remember, even though people ask, “is steel waterproof?”, the reality is you have to protect steel from long-term water exposure if you want it to last.
When to Use a Different Rod
While 7018 can work, if the job is important or the weld will be in a harsh environment, consider using a rod specifically made for stainless steel. These rods are designed to handle the mix of metals better and resist cracking and corrosion.
If you have the choice, a stainless steel electrode or a nickel-based rod is a safer option for joining stainless to mild steel. But if you’re working with what you have on hand, 7018 can still do the job with the right prep and care.
Final Thoughts
So, can you weld stainless steel to mild steel with 7018? Yes, you can. It’s not the perfect method, but for many DIY projects and small repairs, it works fine if you prepare the metals, use proper technique, and protect the weld afterward.
Always keep in mind:
- Stainless and mild steel react differently to heat and moisture.
- 7018 can make a good joint, but it’s not as corrosion-resistant as special stainless rods.
- Protect the weld with paint or coating, especially if water is involved.
Whether you’re fixing a frame, building a project, or attaching a stainless steel t section to mild steel, 7018 rods can help you get the job done. Just remember that steel isn’t waterproof, and if your project will face water, protect your weld to make it last. And if you’re wondering whether you can put magnets on stainless steel, the answer is yes for some types, which can be handy when lining up pieces before you weld.
By understanding these simple points, you’ll be better prepared to mix metals safely and make a weld that holds strong.