If you’ve ever wondered how steel chain saw guide bars are made, we’ve got you covered. What looks so simple actually involves a significant process of engineering and manufacturing. A recent visit to the Stihl Plant 2 in Waiblingen-Neustadt, Germany gave us an up-close-and-personal look at how it’s done.
About 80 people work in this department making steel Stihl chain saw bars. Stihl actually uses two different types of guide bars depending on the saw. They have a 3-part guide bar with sprocket nose for smaller saws and a more stable solid guide bar that works for heavier duty applications. Stihl installs the solid bars in their professional-use saws. Or, you can look at it this way:
Three-part Chainsaw Bar with Sprocket Nose Features
- Low weight
- Lower risk of kickback
- Higher cutting performance
Solid Chainsaw Bar
- Sturdy, for tough applications
- Long service life
3-Part Guide Bar Production
In learning how steel chain saw guide bars are made, we started with the 3-part guide bar process. First, a roll of stainless steel supplies the material for the guide bar. That steel feeds directly into a stamping press which cuts out each of the three parts (two external and one internal). The layers are then electro-welded together.
“Electro-welded” sounds like a simple term. In actuality, the three pieces of steel are properly aligned and then go into a welding press. The press applies as much as 20 tons of pressure. It’s at that point they get welded together by means of electrodes. But the process needs one more step. Without precise cooling, the bars would warp. A controlled cooling process keeps the bars straight and even following the welding process.
So much of the process is automated—you may wonder what the factory workers do. In fact, the factory operators’ role deals with changeover processes, quality control, maintenance, and similar duties. Stihl’s people maintain the machines and keep them running.
Continuing the 3-piece steel guide bar manufacturing process, the guide bars also go through an induction-hardening process before the appropriate sprocket nose can be inserted.
An automated machine literally widens the nose and inserts the race-bearing-filled sprocket. A guide piece is placed on top which is filled with rivets. The machine then stamps the rivets into place, locking everything together.
Solid Chain Saw Bar Production
The solid chain saw bar production begins with a solid bar of steel. The steel is laser cut to the desired basic shape, including the outer contour, bores, and elongated hole. Looking at the process, the laser makes very little waste in the cut, and Stihl even reclaims the leftover steel.
Laser welding occurs next which places a Stellite, or cobalt-chromium alloy, onto the nose of the solid bar to make it more durable against wear. After this, the front end is hit with a giant belt sander to grind it smooth. Afterward, it’s brushed clean.
Following this, a high-speed CBN grinding wheel cuts in the side channels.
Painting the Chain Saw Bars
The last step with how steel chain saw guide bars are made has to do with painting the chain saw guide bar. The painting process is fully automatic. It applies a thin coating of water-based paint without any significant overspray before it goes into the drying process. How thin? The thickness of the dry layer sits between 0.025 and 0.030 millimeters.
Before considering the bar complete and the process finished, a digital inspection system checks for any imperfections. Logos and final branding are then applied before final packaging and distribution.
Conclusion of How Steel Chain Saw Guide Bars are Made
Seeing how steel chain saw guide bars are made revealed a largely automated process that leaves little room for error. Stihl has perfected the process. It’s certainly unique since Stihl is one of two major guide bar manufacturers. Instead of grabbing a third-party manufactured bar, the company can customize and design that integral piece of the chainsaw to meet their needs.
For more information, please visit the Stihl website.