Rev. 11/18/2025

Follow these spot welding guidelines to ensure consistent, high-quality welds while extending your equipment’s life and maintaining safety standards. These best practices cover electrode selection, cooling systems, maintenance, and process control.

Electrode Selection and Installation

Choose the right electrodes. Use only welding electrodes of the specified type and shape, and make sure you clean them before installation. Never use electrodes of unknown material. Choose straight electrodes when possible, and only use offset electrodes when nothing else will do the job.

Position deflector tubes correctly. Always check the location of the deflector tubes (water tubes inside the electrode) when you install electrodes. Make sure they extend well up into the electrode cooling recesses.

Prevent electrode freezing. When you won’t use an electrode holder for several days, remove the welding electrodes to prevent them from freezing into the holder due to corrosion.

Cooling System Best Practices

Verify water flow before welding. Always check the flow of cooling water to the electrodes, transformer, and SCR contactors before you begin welding.

Use correct hose sizes. Always use the correct size hose to supply cooling water to these component parts. When you must remove hoses from the water connections, look into the ends before you reassemble them to ensure no loose material will partially block the hose.

Repair leaks immediately. If a leak develops or exists in any part of the cooling system for your equipment—including water hose connections—correct it immediately.

Electrode Care and Dressing Guidelines

Dress electrodes with fine emery cloth. Use fine emery cloth to dress welding electrodes. If the electrodes have deteriorated to a point where such methods prove inadequate, remove them for machine dressing.

Minimize metal removal. If you instruct a mechanic on how to machine dress electrodes, tell them to remove the minimum amount of metal. Resistance welding electrodes come from valuable alloys that you should not waste by removing more metal than absolutely essential. We do not recommend using files for dressing electrodes. You may use certain contour files designed for this purpose with discretion.

Never use Teflon tape for sealing. Never use Teflon tape to prevent water leakage around electrodes. If the weld taper will no longer seal, replace the electrodes or holder.

Equipment Maintenance and Safety

Protect your equipment. NEVER STRIKE A CONDUCTING PART OF YOUR EQUIPMENT WITH A STEEL HAMMER. If you need to apply a blow to move a tip holder or arm, use a rubber, rawhide, or plastic mallet—never a steel hammer.

Maintain secondary circuit connections. Make sure all mechanical connections in the secondary circuit of your welders stay tight and clean. Keep an eye out for damaged shunts and cables.

Follow maintenance schedules. Always perform maintenance regularly as scheduled. This includes cleaning and lubrication.

Process Control

Understand sparking. Keep in mind that sparks in resistance welding indicate problems and signal a borderline balance between current and pressure. When you encounter frequent sparking or expulsion of metal from the joint, check the squeeze and hold time. Material conditions also factor in, while adequate pressure between the tips remains essential to freedom from sparking.

Minimize throat extension. As much as possible, do NOT extend metal into the throat of your machine. Remember that ferrous metals react in the throat of the machine secondary, increasing their reactance, which will reduce the available amperage necessary to produce the weld.

Apply These Spot Welding Guidelines Today

These spot welding guidelines help you maintain consistent weld quality, extend equipment life, and prevent costly downtime. Make them part of your standard operating procedures for best results.