Jiffy-Tite Cooling Components
Published

The Tool of Choice for Mold Repair

Manual laser micro-welding systems are an alternative to traditional microscope GTA welding.

James E. Gervais

Share

Today’s small precision welding shops specializing in plastic injection mold, die and tooling repair have a wide range of new technologies available to enhance their ability to provide the highest level of quality, craftsmanship and service to their clients. One of the fastest growing technologies is the use of manual laser micro-welding systems as an alternative to traditional microscope GTA welding.

Laser is an acronym for Light Amplification by the Stimulated Emission of Radiation. This technology produces a sharply focused beam of hot light that melts a very small area of metal and can be used to join similar or dissimilar alloys.

The welding process can be performed quickly (normally in milliseconds) and does not scar or blemish the welding surface. In fact, by adjusting the laser’s beam diameter, a smooth, near polished finish can be achieved with the laser.

Since very little heat is generated at the weld point, users can easily weld 0.10mm away from the most complicated and intricate machined patterns, polished surfaces and removable component assemblies.

Lasers can be used to fill porosity, re-fill damaged surfaces including porosity and pits, run a bead of alloy along a complex edge and correct manufacturing defects. Laser welding reconfigures the molecular structure of either similar or dissimilar metals at the point of welding—allowing the two common alloys to become one.

Tool and die shops currently using laser welders are often amazed at the wide range of applications and ability to produce a higher quality product in less time with fewer materials while eliminating excessive heat effects.

 

How the Laser System Works

One of the key elements in making laser welding applicable to tool and die repair was the development of the “free-moving” concept. In this approach, the laser generates a stationary infrared light pulse, which is targeted through the microscope’s cross-hair. The laser pulse can be controlled in size and intensity.

Because the heat generated remains localized, operators can handle or fixture items with their fingers, welding small areas with pin-point accuracy without causing any harm to the operator’s fingers or hands. This free-moving concept enables users to eliminate costly fixturing devices and increase the range of assembly and repair applications.

In laser welding systems, the operator controls the beam diameter (weld spot), power level (voltage), and pulse length depending on the type of alloy and joint being welded. A stereomicroscope with internal cross-hairs makes it easy for the operator to align and weld the component part or assembly at the precise location. The laser pulse is then activated with a foot pedal. Many systems also offer the option of a cover gas—normally Argon—to ensure a homogeneous weld while preventing any discoloration or contamination.

Most operators can learn to use laser welding machines in a few hours, although to become fully proficient and benefit from the machine’s full potential, users must have a good understanding of the metallurgical properties of the alloys being welded. An experienced laser welding technician can typically perform basic manipulation of the repair item within minutes.

Laser spot-welders pose little hazard to operator’s fingers or hands while in the welding chamber. Occasionally, an operator’s fingers may experience a deflected laser pulse, but little damage is done. It is similar to a pin-prick or touching something hot.

To ensure the safety of your laser welding system, always ask the manufacturer before you purchase if the machine is FDA-certified according to the safety standards established by the Laser Institute of America.

Since most manual laser welders range in pulse energy from 40 to 150 joules of energy, or 30 to 150 Watts, they are normally categorized as a Class 4 laser device—the highest powered Nd:YAG laser available. When the welding chamber is fully enclosed, the system meets the Class 1 safety standards, which is the safest laser to operate.

 

Into the Future

During the last few years, the price of many laser welding systems has decreased, making them increasingly affordable to plastic injection mold manufacturers, small tool and die workshops, precision welding repair shops, and prototyping laboratories while offering additional features and flexibility for the user. Frequently, those who have purchased the laser systems find that the time, labor and material savings realized far outweigh the original purchase price.

MoldMaking Technology Magazine
MMT Today enews
Data Flute
Date Code Inserts
Progressive Components
KM CNC Machine Service
North America’s Premier Molding and Moldmaking Event
Bonal Meta-Lax Stress Relief Solution

Related Content

Hot Runners

What You Need to Know About Hot Runner Systems and How to Optimize Their Performance

How to make the most out of the hot runner design, function and performance.

Read More
Safety

Think Safety: Eliminate Hazards Throughout the Shop

The tooling community is taking advantage of new products for safer mold shops and molding facilities.

Read More

Precision Welding Services Offer Rapid Turnaround Mold Repair and Reduced Molder Downtime

X-Cell Tool & Mold relies on outsourced, high-quality welding repairs from Lewis-Bawol Welding to ensure its customers' molds are back in production quickly and affordably.

Read More

Hands-on Workshop Teaches Mold Maintenance Process

Intensive workshop teaches the process of mold maintenance to help put an end to the firefighting culture of many toolrooms.

Read More

Read Next

Basics

Laser Welding Versus Micro Welding

The latest battle in finely detailed restoration/repair of mold materials.

Read More
Tool Steel

The Value of a Shop’s Welding Policy

To put the appropriate welding policy in place, you need to choose the right welder—someone who is familiar with tool steel and has a working knowledge of molds.

Read More
Basics

How to Choose the Best Welding Method for Your Mold Application

Moldmakers can save time and money on repairs by understanding the similarities and differences of conventional and micro TIG..

Read More
Top 5 Reasons