MIG Accessories FAQs
Straight answers to the questions people ask most when choosing and using MIG welding accessories and consumables.
What is a CO2 heater and do I need one?
When carbon dioxide leaves the cylinder it expands and gets very cold, and at high flow rates or in long periods of welding this can freeze the regulator and reduce or stop the gas. A heater fitted between the cylinder and the regulator warms the gas and prevents this.
It is mainly needed when welding with pure carbon dioxide at higher flows or for long stretches. For argon mixtures at normal flows it is not usually needed. Heaters run from an electrical supply, so follow the maker's instructions and keep them away from water.
How do I keep the nozzle clean of spatter?
Spatter builds up inside the nozzle and, if left, narrows the gas path, which disturbs the shielding gas and causes porosity. Clear it regularly using a reamer or the jaws of the MIG pliers, with the torch cool and the machine switched off.
Avoid hammering the nozzle or scraping it with sharp tools that might scratch it, because scratches give spatter a place to stick. Using anti-spatter in moderation helps, and replacing a nozzle that is badly worn or damaged is better than cleaning it again and again.
Is anti-spatter spray or gel worth using?
Anti-spatter makes spatter easier to remove from the nozzle, tip and workpiece, and reduces the time spent on cleaning up. It is applied lightly to the nozzle or onto the surface near the joint.
There are some downsides. Some products contain silicone, which can cause problems if the work is going to be painted or coated afterwards, and there are silicone-free types for that. Do not overdo it, and avoid getting it on the contact tip or in the wire path. Follow the maker's safety information.
Are small gas cylinders enough for hobby MIG welding?
Small cylinders are handy for occasional light jobs because they are light and easy to store, but the gas does not last long, so they are not suited to regular or heavy welding. How long one lasts depends on the flow rate and how much you actually weld.
If you weld often, a larger refillable cylinder is usually more practical. Small cylinders need a regulator and, in some cases, an adaptor made for them, so check what fits. Never refill or tamper with a disposable cylinder.