Preparing Plastics for Welding

Proper surface preparation is almost as important as technique when it comes to plastic welding. Improper preparation leads to weaker welds and can cause premature failures. 

Welding area & weld rod must be:

• Clean and dry
• Free of oil and grease
• Free of cracks or notches
• Free of oxidation

Material preparation: 

• If not already present, create a V-shaped groove where weld will be
• Remove any dirt, debris, grease, or other contaminants from parent material and the welding rod
  • Do not use industrial cleaners – they can leave residues behind
• Scrape the area for welding on the parent material to remove the oxidized top layer
  • STANMECH recommends a steel scraper, a Dremel with a tear drop cutting attachment, or a similar mechanical cutting operation
  • Do not use sandpaper or any other grinding medium as this will leave debris, sand, and/or dust in the weld zone
• When hand welding, scrape the welding rod to remove the oxidized top layer
  • When using an extruder, the welding rod does not need to be scraped as it will be ground up and plasticized when it travels through the extruder