laser cuttingLooking after your laser cutter properly is one the best ways to maximize its efficiency and productivity. One task that every operator needs to stay on top of is slat maintenance, making sure slats are clear of the slag that is formed and accumulates each time the laser cutter is used.

Keep reading to learn about the issues that excess slag can cause plus three steps you can take to keep it in check:

The Problems with Slag on Your Slats

Slag is an inevitable by-product of laser cutting. As the laser cuts through the sheet metal, it produces molten material (slag). When the laser moves on to a new cutting area, the slag cools and hardens on the laser cutter’s grated table (the slats) below.

If left unattended, built-up slag can cause a range of problems for operators:

  • Parts can be burnt, discoloured, compromised, or ruined when residual metal from previous jobs comes into contact with them as it’s reheated by the laser.
  • Splatter can be kicked back against the laser cutter itself and damage the machine (or components like lenses).
  • Too much slag will prevent sheets from lying flat against the table, negatively impacting the quality of your parts.

Preventative maintenance and regular slat cleaning is the key to ensuring your laser cutter performs its best and produces high quality parts.

How to Keep Slag off Your Laser Cutter’s Slats

1. Anti-Spatter Agents

When applied to your laser cutter’s slats, an anti-spatter compound creates a barrier for molten residue and metal to adhere to (instead of solidifying on the grating itself). Most operators find they need to apply a fresh anti-spatter coating about once a week, though you might need to increase the frequency if your laser cutter is used over multiple shifts throughout the week.

The ideal anti-spatter agent is one that:

  • Is liquid based (not an aerosol) and can be easily applied using a tank sprayer.
  • Is non-toxic and water soluble, making it easy to remove and ensuring you won’t need to worry about creating any hazardous waste.
  • Won’t contaminate the weld seam.
  • In no way interferes with follow-up activities like galvanizing, priming, or painting.
  • Works on a variety of metals including steel, copper, and other hybrids.

Keep in mind that anti-spatter compounds won’t eliminate slag completely. Instead, they can help to extend the life of your slats and reduce the amount of time and effort that goes into cleaning them.

2. Electric Slag Removers

Electric slag removers make it possible to quickly and easily remove residual slag from your slats. The tools typically feature two serrated elements that move up and down and oscillate while sliding over the slats, enabling them to scrape hardened material off of both sides.

Depending on the design of your laser cutter, it is sometimes possible to clean your slats while the machine is in operation. This is especially the case for laser cutters with pallet changers.

3. Copper or Mixed-Metal Slats

Stainless steel slats have long been the tradition for laser cutters. In recent years, however, more and more operators have been realizing the benefits that come with switching to copper slats.

Although copper slats are more expensive than steel, remember:

  • Because heat is distributed more evenly and quickly with copper, copper slats suffer less wear and tear than their steel counterparts.
  • Copper slats have a longer lifespan than steel slats (four to eight times greater). With the right upkeep, copper slats can last as long as two years before they need replacing.
  • You will still get slag buildup on copper slats, but it won’t accumulate as quickly and it’s easier to remove compared to steel.
  • When it is time to discard of your worn slats, copper is worth significantly more than steel as scrap metal (up to 10 times as much).

If you’re unsure about investing in copper slats, a mixed-metal (or hybrid) option can prove to be a suitable alternative. Mixed-metal slats are made by attaching copper tips to a steel underframe. This gives you the longevity of copper with a price tag that’s up to 30 percent lower. With regular maintenance, mixed-metal slats can last up to four times as long as steel.

Ultimately, combining the right maintenance program (using an anti-spatter agent and an electric slat cleaner) with copper or mixed-metal slats will mean higher quality parts, more manageable maintenance, and an extended life for the slats in your laser cutter.


Westway proudly carries a diverse range of laser cutters from Mazak Optonics, a laser cutting leader and industry pioneer. Contact the experts at Westway today to discuss how a Mazak laser cutting machine can work for your application!

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