Tack Welding vs Spot Welding

Welding two metal pieces together isn’t too difficult for an experienced, well-informed welder. And if you’re keen on making the most from that 140 Amp MIG welder, you’ve got to know how best to join work pieces.

With essential info laid out on welding, it’s certain you’ll come across the terms ‘tack’ and ‘spot’ several times. Tack welding vs spot welding remains popular in the metalwork sphere.

Newbies and skilled pros make use of these join methods every day. But for you to become an expert with your stickmate welder or any other brand, read through this closely.

The info right here will help you make the most from both methods. With all the facts laid out, you’ll know what method fits where. You’ll also have info on how best to carry out each process.

Tack Welding – What is it?

Before two metal plates get a solid join, there has to be proper alignment to avoid leakages and maintain durability. For this alignment to get achieved, short welds in form of tacks are placed at several points where the plates join up.

Tack welding helps keep both work pieces in perfect shape until a permanent join is carried out. Most tack welding processes are common on large metal sheets or challenging work pieces.

With a temporary weld, both parts can be conveniently welded with zero defects and more comfort.

Benefits of Tack Welding

Time saver

Tacking two metal pieces to await a solid join provides operators a lot more time to get jobs completed. With the time-saving potential from a tack weld, more metal plates can get welded in much lesser periods.

Promotes accuracy

With tack welds, you’re able to take a look at both metal pieces from every possible angle before a permanent join. Using tacks promote pinpoint accuracy and will assure you better welding results.

Defect detection

Using tack welds make it more comfortable to point out wrong work piece placement. With defects easily detectible, there’s a greater chance of maintaining greater precision even on challenging pieces.

Easy assembly and alignment

Making use of tack welds provides operators with a freer hand when it comes to re-aligning metal pieces. Rather than going through cumbersome processes to separate two metals, tack welds are easy to remove.

Material saver

Tack welds before the main join op promotes lesser waste. Since you’ve got both plates correctly aligned, you won’t have to spend a lot more electrodes or filler metal on a wrong join.

When Should You Use Tack Welding?

Positioning pieces

While positioning metal pieces, tacks are essential to maintain alignment. Without proper tacks, even if you’ve got the best TIG welder for aluminum, a perfect join may be far-fetched.

Small-sized plates

Getting thin or small plates together for a solid join can be better achieved with a series of tacks. It’s highly likely for smaller pieces to pose a challenge during welding. But with a tack, joining up metals becomes more comfortable than ever!

How Can You Tack Weld?

Stick Welding

When you intend tacking with a SMAW process, follow these steps;

  • Plug ground clamp to one work piece
  • Get your welder connected to a power source
  • Set welder to preferred polarity points
  • Fix an electrode on your welding thong
  • Place the electrode on the central point of two work pieces
  • Hold the electrode and form a join with three second bursts across three to four inch points on metal pieces

Note: Larger metal pieces may need a lot smaller spacing between tacks.

Gas Welding

If you’ve got a MIG machine or the plates and need a tack, here’s what you’ve got to do;

  • Get your tungsten welder ready
  • Prepare shielding gas
  • Connect your welder to gas tank
  • Fit gun nozzle
  • Point the nozzle onto metal pieces
  • Pull trigger to form a small weld pool
  • Space out the tacks as desired to maintain a strong grip

Downsides of Tack Welding

With a tack weld, you can only wish the join remains in place. An average amount of pressure may cause tacks to break off, making it a not-so-great permanent join method.

Spot Welding – What is it?

After tack welding your metal pieces, the next step involves making use of a stronger join to keep both pieces together. That’s where spot welding comes in.

Spot welding makes use of electrical reactions across electrodes or filler metals. With electrical current passing through these resistive materials, heat energy causes the materials to melt.

When these materials melt, a weld pool forms that cools and solidifies, joining both work pieces together.

Benefits of Spot Welding

Stronger joins

Unlike tack welding that mostly holds both metals together with a light blip, spot welds go a lot deeper. These welds are formed after a heat reaction melts electrodes onto both work pieces. After the pool cools down, what you get is a solid join.

Varying applications

Unlike other welding methods, spot welding is ideal for a lot more than joining two metals together.

Spot welding is a mainstay in medical architecture, electronics, and other sectors. Its easy-to-use methods coupled with a high precision potential make it an excellent choice for many industries.

When Should You Use Spot Welding?


After tacking two metal pieces and don’t need an end-to-end weld, your best option is to go for a spot weld.

Precision welding

If you’ve not got your sights set on a full-on weld, spot welding will help you join up two pieces at required points.

Final Word

Now that you’ve seen both processes in detail, it’s now more comfortable to know the difference between tack welding vs spot welding.

It’s guaranteed that after this read, you’ll know what welding method fits where. Apart from knowing what method works for each situation, you’ll have a lot more comfort in getting your join operations done in time.