Flux Core Welding 101: (Complete Guide For Beginners) – 2020

Flux Core Welding

Beginner at welding?

Want to do flux-core welding?

If you are impressed with the flux-core welding projects and want to do it on your own, we are here to help you with some tips.

This guideline is only for you if you want to walk through the road of flux-core welding.

The reading of this writing will provide the necessary information to do flux-core welding and this will help you to get the best results.

I am confident this guideline is a complete package of tips that you have been looking for.

What Is Flux Core Welding?

As we are talking about the basics of flux core welding for a beginner, it is also important that he/she knows what it is? 

The flux core welding method is not totally different from arc or MIG welding methods.

The reason behind naming it a flux-cored welding is that a wire made of flux is used to weld by this process and this is what covers the whole weld.

To be noted, it is a sort of arc welding process that can be both automated or semi-automated. 

The flux of the welding wire increases the durability and the longevity of the weld.

It cools down really slow compared to the other welding methods.

It can do well in the case of manufacturing because of its great portability.

The flux makes a shield on the surface and makes a strong hold.

This is why there is no need for a gas tank for the flux core. 

People have a traditional belief in them that only stick welding is the best method to do outdoor welding.

The flux core welding method has changed the situation now.

You can weld by this technique by being careful and following the method strictly.

Well, there is one thing to consider if you are doing flux welding. 

It is the wind.

A good blow of wind will also blow the shielding you have set up.

You should be also careful about the wire.

The self-shielded wires come up with traditional problems.

So, be careful about that too. 

Well, that has turned out to be a huge intro about flux welding.

I am going to put a stop here about it as I have discussed enough about the method. 

Now, let's do the first things first. Let’s learn about the basics of flux welding. 

Preparing the workspace:

Before welding, preparation is mandatory. 

Preparation will help you to avoid unwanted fires and injuries.

The best preparation is to prepare your workspace by removing the things which might catch fire.

The second suggestion is not to do welding in enclosed and low ventilation areas.  

Safety measures:

There are some safety measures which you should take for your own safety. They are listed below. 

  1. Wearing safety glasses
  2. Welding jacket
  3. Welding gloves
  4. Leather apron
  5. Work pants
  6. Work Boots

In a nutshell, your clothes that you will wear while working have to be resistant to fire. 

You can check out our guide to personal safety equipment

Surface preparation:

I must mention here that flux core welding is more tolerant to weather contamination than MIG welding. So, to ensure less contamination of the welded surfaces it is necessary to prepare the metal surface first. 

A wire brush shall be used to clean the rusty metal surface. Be sure to clean the surface of the base metal where the ground clamp will be attached to. If the clamp is less contacted with the surface ground, then it might lead to a welding of poor quality. 

Preparing equipment:

A good preparation of welding equipment ensures safety and a good quality welding.

This is why it is necessary to check and prepare the instruments before welding.

Check your cables: 

The cables are the most important parts in flux-core-welding.

If not properly maintained they can be the reason behind accidents too.

So, double-check if they are properly connected or have any damages in them. 

Determine the polarity of the electrode:

Flux core welding requires a negative DC electrode or straight polarity.

The connections are found inside of the machine near the drive rolls. 

Using proper drive rolls:

The wires that are used to flux-core-welding are softer than solid wires.

The drive rolls play a vital role with the wire that prevents it from compressing or deforming.

So, choose your drive rolls wisely. 

Wire tension:

Too much or too less tension on any side of the wire leads to poor feeding performance.

Adjusting as per your user manual will be a wise act in this scenario. 

Discard worn contacts:

It is necessary to remove the unnecessary spatter from the contact tips and discard them if the wire appears to be rusty.

This will consume less energy. 

Selecting Wire:

Not only for flux-core-welding, a proper selection of wire is also necessary for all sorts of welding procedures. 

You might not want to even imagine what might happen if you do not select the proper wire. 

If you are doing a mild steel welding, then it will be wise to use the E71T-11 Flux core wire.

It is a versatile wire and comes in a wide range of shapes and sizes.

It also provides great performance on both thick and thin materials.

We even have listed the best wires for flux-welding for you.

Do check if you want to find the best ones for you.

Now, what will be the diameter?

It would be better to stick with 0.30 inches.

This is a diameter that is suitable for general purposes and versatile as well.

If you are using a high temperature to weld a thick metal, then go for .35 inches.

For your information, the highest diameter range is 0.45 inches for powerful welder ranges.

Voltage And Amperage:

Spending on metal thickness, the voltage, and amperage differs in welding.

The other factors are joint configuration, the welding position, and the wire diameter.

You will find charts or online calculators which will help you set up the voltage and amperage requirements as per your metal. 

It makes your performance and these little adjustments tunes fine into a good welding.

Wire Stick Out:

The stick-out of wire means the unmelted electrode length that starts from your contact tube tips.

The arc length is excluded from this measurement.

It requires ¾ of an inch for a stick out length in the case of flux-core-welding.

This is two times more than regular and common MIG welding. 

Push Or Drag?

The common confusion among the new welders is what to do while flux-core-welding? 

Shall I drag? Or push?  

It is better to drag when you are doing flux-core welding.

The push makes the MIG result in the slagging in your welding puddle. This results in a bad welding. 

The dragging of the torch ensures the proper landing of your spatter and minimizes porosity issues. 

There is a proverb behind this fact that goes.

“IF there is a slag. You should drag”. 

The best utilization of dragging is found by pointing the tip of the welding gun backwards and towards the welding pool.  

Travel Angle:

The travel angle is that angle which is defined when the gun is in a perpendicular position within the joint plane.

The normal travel angle for all sorts of conditions and positions are from 5 to 15 degrees.

The more the travel angle, the welds result in more spatter, less penetration, and the instability of the arc. 

Angle Of Working:

The working angle defines the holding angle of your gun while working.

This angle differs as per the welding position and joint configurations.

Have a look below for better understanding. 

Flat positions:

This position is also known as the butt weld position.

This is a 180-degree joint in which your gun should be held at 90-degree angle. 

This angle should not change with your working position.

Using side-to-side small motions you should direct the filler material right into the joint.

The traveling angle should be 5 to 15 degrees.

This method helps you to fill up a huge gap and allows multiple passes. 

The normal 90-degree welding joints look as “T” shaped.

These types of joints are also known as a fillet.

You should keep your gun at 45 degrees in order to do welding perfectly.

The equal distance from each join should be maintained.

To avoid uneven beads of filling, the working angle can be changed slowly from one side to another. 

Now we have the Lap joints. 

This type of fillet weld requires you to hold a gun at 60 to 70 degrees.

This directs heat at the bottom of the metal.

Depending on the thickness of the metal the angle of welding can be changed. 

Horizontal positions:

To accommodate the welding well, the angle should change among 0 to 15 degrees.

Gravity provides you a helping hand in this position.

It provides some force to your welding. 

The necessity of not changing the travel angle here is because it might lead to a filler that rolls over the bottom joint part.

While doing welding in a horizontal position, the welding torch should face upwards to the top metal piece. 

Do not worry if you are welding thick metals or need to bridge a gap with a bad fitting.

A slight weave is a great solution to this issue.

Ensure that there is a proper tie into the base metal, to prevent your welding from undercuts otherwise take a little pause.

The voltage and amperage remains constant but is a bit lower than flat welds.

Vertical position:

The vertical position is a tough position to weld.

For this type of welding pre welding setup is necessary.

In this position, you will be fighting against gravity.

This is why considering voltage and amperage is also necessary.

It should be from 10 to 15 percent. 

There are two techniques to be followed in this position of welding. They are

1. Vertical down: 

In this technique the arc penetrates less as the travel speed is faster. 

To weld you should start at the top of the joint to the down of the weld.

You should weave side to side slightly as well.

To avoid burning through, keeping the electrode on the leading edge is a useful method. 

2. Vertical Up:

This technique is the same as the previous one but provides better penetration on thick materials.

The travel angle should be 5 to 15 degrees down with a weaving motion in a perpendicular position. 

Overhead position:

This is the position that experts highly recommend to avoid if possible.

You should try to use the shortest wire possible if you are doing an overhead position welding.

Lower your parameters by 15 to 20 percent and maintain a fast speed. 

Wire Feeding Issues:

There are two types of problems that you will face while doing welding.

These issues are responsible for wire extinguishing and causing welding defects. 

If your wire melts and takes the shape of a ball on the tip, that is known as Burn back.

Such happens when you feed the wire slowly or the gun is too close to the metal.

The right feeding speed and maintaining the distance from the metal is the solution to this problem.

In Bird Nesting, the wire gets tangled and the feeding gets stopped.

Using the knurled drive rolls to solves this issue. 

Porosity And Worm Tracking:

These two issues are also very common in welding. 

When the gas is jailed into the weld’s metal, this is when porosity happens.

The suggestion is to remove rust, grease, etc before starting the welding.

The filler materials also help. Use the ones that are deoxidizers. 

On the other hand, work tracking happens when your gas causes marks on the weld.

Being strict to the voltage and amperage parameters as per the wire’s diameter and metal thickness is the solution. 

Less slags:

We have been talking about this problem since the beginning of this writing.

To avoid this, dragging and pushing while welding should be done.

The dragging of the arc keeps the spatter away from the joint and provides you the best joint. 

Try not to push if you do not want any slags in your welding.

Undercutting and less fusion preventions:

The right work angles and the right traveling speed are the good savers in this case.

Use the right welding technique for particular joints.

Weave or push as per the technique to solve this issue. 

Penetration:

A proper penetration determines the perfect fusion with the metal.

This ensures a great safety and lifespan. 

It can be excess or less.

If you are dealing with a lack of it, weld vertically upward.

If you want a great penetration then flux core welding is the best solution.

The uphill motion in a vertical position provides extra penetration.

It provides a stronger weld than horizontal. 

Conclusion:

We all are familiar with the proverb that “Practice Makes a Man Perfect”.

Welding being a skill requires the same.

Do not lose hope if your first welding does not reach your expectations.

Follow the above steps for a more success rate. 

This guideline is only to improve your skills as a beginner.

I am confident that the proper following of this guideline will be of great use to you.

Now, practice!

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