One of the major advantages of thermoplastic membranes is the ability to have their seams hot-air welded. When heated sufficiently, thermoplastic membranes change from a solid to a semi-solid state, enabling the sheets to be fused together. Thus, a monolithic (continuous) membrane is created.

Sika Roofing is the only membrane manufacturer that designs its own hot-air welding machines.  For the most reliable and permanent seam welding, Sika’s authorized applicators use a Sarnamatic hot-air welder.

For smaller, hard to reach areas or for use around details, a hand-held hot-air welder is used.

Sika Sarnafil Sarnamatic-681 Hot-Air Welder

How hot-air welding works:

Heated air is blown into the seam area, causing the membrane surfaces to melt. A roller and the weight of the machine then presses the two sheets of membrane in the overlap together. As the welder moves away from a given seam location, the membrane quickly cools down to ambient temperature and the heat weld is completed, providing a watertight, permanent bond. When complete, the welded seam is actually stronger than the surrounding membrane.

Sarnamatic 681 – the smart hot-air thermoplastic membrane welder

As successor to the well-proven Sarnamatic 661 SpeedWeld, the Sarnamatic 681 boasts some extraordinary features. In fact, it sets a whole new standard for reliability, safety and convenient operation.

Sika Sarnafil's Sarnamatic-681 Hot-Air Welder
Reliable Results
Wide tolerance against voltage fluctuations
Error messages displayed as text
Field replaceable parts
Easy to Use
4.3" TFT color display for easy reading in daylight
Simple menu operation
Compact for easy handling
Clear, easy-to-understand error messages
Welding parameters for different Sarnafil membranes are stored in memory
Adjustable nozzle unit for perimeter edge welding
Adaptable to Décor Profile welding
Quality Welding
Vertical, free-floating nozzle and pressure wheel that automatically compensate for substrate irregularities
Advanced air trap for crease-free and wrinkle-free seams
Narrow nozzle and pressure wheel provide a consistent weld over a variety of substrates
Customer Support
Service and support are important considerations in your selection of a hot-air welding machine. Sika Roofing understands how critical it is that your equipment work correctly
On-site Support
Sika Roofing field technicians are available for training and on-site support. The interchangeable parts on the Sarnamatic 681 also allow your staff to quickly and easily service the welder on-site, minimizing worker downtime
Factory Service
In the event that your Sarnamatic 681 needs factory service, our Sarnamatic Service Department will provide quick and efficient service. Every Sarnamatic 681 carries a two year limited warranty, one of the longest in the industry

The Handheld Hot Air Welder

A hand-held hot-air welder is used mainly for seams at details. The Triac welder comes equipped with a 40 mm and a 20 mm wide welding nozzle and a pressure roller. With a digital display of set and actual temperatures, the Triac hand-held welder provides optimum welding results.