Many people starting with a MIG welder run into a common issue: the wire melts back to the tip. This is often called burnback. It can be frustrating, especially when you’re just learning.
But don’t worry! We’ll show you exactly how to fix the MIG Welder Burnback Problem? How to Solve.
We’ll walk through it step by step so you can weld smoothly.
Key Takeaways
- You will learn what MIG welder burnback is.
- We will explain why burnback happens.
- You will find out how to prevent burnback.
- We will show you how to fix burnback when it occurs.
- Simple settings changes can make a big difference.
Understanding MIG Welder Burnback
What is MIG Welder Burnback?
MIG welder burnback is when the welding wire, after you stop welding, continues to melt and sticks to the contact tip inside your welding gun. It looks like the wire has fused to the very end of the metal tube that guides it.
This can cause a few problems. First, it makes it hard to start your next weld. You might have to pull the stuck wire away or even cut it.
Second, if it happens a lot, it can damage your contact tip, making you replace it more often. For new welders, seeing this happen can be confusing and make you feel like you’re doing something wrong.
Why Does Burnback Happen?
Burnback usually happens because of heat. The wire is hot from welding, and if it stays hot for too long after you release the trigger, it will melt back. There are a few main reasons for this:
Too Much Voltage
When the voltage is too high for the wire speed, you get too much heat. The wire melts faster than it’s being fed. Think of it like trying to melt butter with a really hot flame; it melts too fast.
Wire Speed Too Low
If the wire speed is too slow for the voltage you’re using, the same problem occurs. The wire isn’t feeding fast enough to keep up with the melting. It’s like a slow conveyor belt trying to carry away hot metal; it can’t move it fast enough.
Arc Length Issues
The arc length is the distance between the wire tip and the metal you’re welding. If this gap is too wide (too much arc length), it creates a hotter arc. This extra heat can cause the wire to melt back to the tip.
Stopping the Arc Incorrectly
How you finish a weld matters. If you stop feeding wire and releasing the trigger too quickly, the wire can keep melting. The heat from the weld pool has nowhere else to go but back up the wire.
Dirty Contact Tip
A dirty or worn contact tip can cause poor electrical contact. This can lead to inconsistent heat and make burnback more likely. It’s like a loose connection in an electrical plug; it doesn’t work right.
Incorrect Gas Flow
While less common, incorrect shielding gas flow can sometimes contribute. If the gas isn’t protecting the weld pool properly, it can affect heat buildup.
How to Solve the MIG Welder Burnback Problem
1. Adjust Your Settings (The Quick Fix)
Often, burnback is just a matter of finding the right balance between voltage and wire speed. This is the most common solution.
Finding the Right Wire Speed and Voltage
Most MIG welders have settings for both wire speed and voltage. These are usually linked. For a given thickness of metal, you’ll have a range of settings that work well.
A good starting point is to set your voltage and then adjust your wire speed until the arc sounds smooth. It should sound like a steady sizzle, not a rough crackle or popping. If you hear popping, your wire speed might be too low for the voltage.
If it sounds like the wire is melting too fast and splattering, your voltage might be too high for the wire speed.
| Problem | Likely Cause | Solution |
|---|---|---|
| Burnback (wire sticks to tip) | Voltage too high OR Wire speed too low | Lower voltage OR Increase wire speed. Find the balance. |
| Spitting/Popcorn sound | Wire speed too low OR Voltage too low | Increase wire speed OR Increase voltage. Adjust for a smooth sizzle. |
| Arc too long/stringy | Voltage too high | Lower voltage. |
Refer to your welder’s manual. Many manuals have charts that suggest starting settings for different types of wire and metal thickness.
2. Improve Your Stopping Technique
How you finish a weld is just as important as how you start it.
The “Hold and Release” Method
When you finish welding, don’t just let go of the trigger. Try this:
- Continue to feed wire for a split second after you stop moving. This pushes a little more wire out.
- Then, release the trigger. This action helps push any molten metal away from the tip.
This small pause helps ensure the wire melts at the end of the weld bead, not back at the tip.
3. Keep Your Contact Tip Clean and in Good Shape
The contact tip is crucial for a good weld. If it’s not in good condition, it can cause problems.
Cleaning the Tip
After every few minutes of welding, or if you notice burnback, clean the contact tip. You can use a wire brush or a file designed for contact tips. Remove any excess metal or spatter that has built up.
Checking for Wear
Over time, the hole in the contact tip can enlarge or become misshapen. If the hole is too big, the wire won’t be guided properly, and heat can build up. If your tip looks worn, replace it.
They are inexpensive parts.
Make sure the tip is screwed in tightly. A loose tip can cause poor electrical contact and inconsistent welding.
4. Use the Right Wire for the Job
Different types and sizes of welding wire have different melting characteristics. Using the correct wire for your project and welder settings is important.
Wire Diameter
Thicker wires generally require more heat (higher voltage and wire speed) than thinner wires. If you’re using a wire that’s too small for the heat you’re putting out, it can melt back.
Wire Type
Solid wire with shielding gas (like ER70S-6) behaves differently than flux-cored wire. Flux-cored wire often has a wider operating window and can be more forgiving. Ensure you are using the correct wire for your welding process.
5. Check Your Shielding Gas
Shielding gas protects your weld from the air. If it’s not working right, it can cause issues.
Gas Flow Rate
Ensure your gas flow rate is set correctly. Too little gas means poor shielding and potential burnback. Too much gas can cause turbulence and also affect the weld.
A good starting point for most MIG welding is 15-25 cubic feet per hour (CFH).
Check for Leaks
Make sure there are no leaks in your gas hose or connections. Also, ensure you are not welding in a drafty area, as wind can blow the shielding gas away.
6. Maintain Proper Stick-Out
Stick-out is the length of welding wire that extends beyond the contact tip. This length affects how much heat the wire absorbs before it reaches the weld puddle.
Ideal Stick-Out
For most MIG welding with solid wire and gas, an ideal stick-out is about 1/4 inch to 3/8 inch (6-10 mm). If your stick-out is too long, the wire has more time to heat up and melt back. If it’s too short, you might get less penetration.
Adjust your welding gun angle and distance from the workpiece to maintain a consistent stick-out during the weld.
When Burnback Still Happens
If you’ve tried these steps and still get burnback, consider these possibilities:
- Check your liner: A damaged or kinked liner can cause the wire to feed poorly, leading to inconsistent wire speed and burnback.
- Check your drive rolls: Worn or dirty drive rolls can slip, causing the wire to not feed smoothly. This can also lead to burnback. Make sure they are the correct size for your wire.
- Test your welder: In rare cases, there might be an issue with the welder itself. If you suspect this, consult your welder’s manual or a service technician.
Frequently Asked Questions
Question: What is the most common reason for MIG welder burnback?
Answer: The most common reason is that the voltage setting is too high for the wire speed, creating too much heat.
Question: Can I fix burnback while I’m welding?
Answer: Yes, you can often fix burnback by adjusting your wire speed or voltage settings during the weld. You can also try a different stopping technique.
Question: How often should I clean my contact tip?
Answer: It’s a good idea to clean your contact tip every few minutes of welding, especially if you notice issues like burnback or inconsistent welding.
Question: What is “stick-out” and why does it matter for burnback?
Answer: Stick-out is the length of wire extending from the contact tip. If it’s too long, the wire heats up too much before it melts, causing burnback.
Question: Should I use a different wire size to prevent burnback?
Answer: Sometimes. If you are using a very thin wire on a high heat setting, it can burn back. Using a slightly thicker wire might require less heat for the same penetration, helping prevent burnback.
Final Thoughts
Fixing MIG welder burnback is about finding the right settings and using good welding habits. You learned that burnback happens when heat builds up. Too much voltage or too little wire speed are common causes.
Keeping your contact tip clean and using the right stopping technique also make a big difference. With these simple tips, you can stop that wire from melting to the tip. You’ll get smoother welds and enjoy welding more.
