Repairer Driven News
« Back « PREV Article  |  NEXT Article »

Tips & tricks to replicate OEM seam seals

By on
Collision Repair
Share This:

During this year’s SEMA Show, Teroson Head of Collision John O’Neill shared some tips and tricks for collision repairers on matching OEM seam sealers and textures with the most important being the type that’s used and with proper tools.

“There’s really not a vehicle that I can think of that doesn’t have these difficult ribbon seams or sprayed seams often,” O’Neill said during a Society of Collision Repair Specialists (SCRS) Repairer Driven Education session earlier this month. “It started with just a tub of seam sealer, brushable, way back in the day; even before my time where we’re just packing seams and covering seams as best we can with acid brushes and horse hair brushes. But there wasn’t really a lot of decor in it.”

He called that process “slap it on, cover up the seam and get it out the door” and noted the process as much more complicated now. And seam sealers, he said, don’t just serve the purpose of keeping water, dirt, debris, and wind out. They also help with sound damping.

While later seam sealers came in cardboard cartridges then foil sausages, both improvements, they had bead and nozzle size limitations and still didn’t replicate OEM seals very well, O’Neill said. The conclusion: aluminum cartridges are the best. “The fine threads allow us to kind of add different nozzles to that cartridge to replicate different seams, different beads. They can be heated up to manipulate that seam a little bit more because it’s not plastic.”

However, there are two drawbacks — it can dent and there isn’t a lot of adaptation for conditional nozzles, he added.

The standard has become a 1K aluminum seam sealer with a bottom side polymer or a 2K seam sealer that’s a 200mL side-by-side cartridge.

“The equipment is now catching up to the material,” O’Neill said. “There used to be kind of just that one nozzle, one gun, and the ‘we’re pulling for you’ approach. We’re really trying as an industry to look at how we incorporate nozzles, equipment, and material all-in-one to make it look just like factory.”

Modified styling polymers are the best as a 1K and polyurethane seam sealers are better unless you’re working with a solid-based product. In that case, O’Neill recommends at least moving up to polyurethane for “faster work times…better strength, [and] better color profiles.”

As for tools, an automatic piston-driven gun with a sprayable feature is essential, according to O’Neill. “They make your life 10 times easier and they make the beads look as close to factory as possible.”

Another helpful tool is a heater box that preheats aluminum cartridges, which takes 20-30 minutes, and gives repairers a lot more opportunity to do different things such as laying beads out for a ribbon seam in a couple of minutes versus taping for 45 minutes to an hour before applying product, O’Neill said.

All of the work some repairers may be doing to make seams look like they’re fresh from the factory, like taking a comb, brush, spreader, or scuff pad to decorate the seam only makes it look close. “There’s a lot of wasted labor time taping. There’s a lot of material that still stays on the tape once I tool it off. What we would really like to be able to show you is a better transfer efficiency.”

Other tips and tricks:

    • Use pinking shears and a spreader for a rake look in trucks for liquid applied sound damping (LASD);
    • Heat (gun, flame, etc.) to manipulate a soft spreader over an existing factory bead to get proper dimensions;
    • Apply product on packaging tape, allow it to cure, and peel it off. Stick into place with fresh seam sealer; and
    • Cut off existing seam sealer and reuse.


Featured image: Teroson Head of Collision John O’Neill (Lurah Lowery/Repairer Driven News)

Share This: