# Web Guiding System Installation - Key Techniques and Considerations > Proper installation techniques for web guiding systems. Essential elements such as 90-degree wrap at the entry and exit of rollers, and others **Last updated:** 2026-03-03 **Source:** https://live-roll2roll.pantheonsite.io/videos/web-guiding-system-installation-key-techniques-and-considerations --- This video, part of the Web Guiding Fundamentals webinar series, focuses on the proper installation techniques for web guiding systems. It covers essential elements such as maintaining a 90-degree wrap at the entry and exit of rollers, recommended span lengths, and the ideal positioning of sensors for optimal control and stability. Key considerations include sensor placement within the first half of the exit span, ensuring the plane of motion of the carriage is perpendicular to the spans, and the implications of bending and steering effects on web stability. Learn how to achieve precise web guiding with expert insights on sensor and roller configurations. 00:00 Introduction to Web Guide Installation 00:25 Sensor Placement and Span Length Considerations 00:54 Carriage Motion and Correction Mechanisms 01:35 Multiple Roller Configurations and Flexibility 01:45 Guiding Action and Sensor Proximity 02:37 Avoiding Common Installation Mistakes ## Transcript [Music] So in terms of installation, we want to make sure that we have a 90° wrap at the entry and exit of the roller. And then there are considerations on the span length at the entry and exit. Usually you can get away with half a web width. We recommend about one to two web widths if possible. If you have a stiffer web like metals, you might need a longer entry and exit span. We want to locate the sensor as close as possible. This is true for any web guide. It doesn't matter if it's a displacement guide, unwind guide, rewind guide, any web guide. We want to have the sensor as close as possible hitting the span where the guiding action takes place. The recommendation is to be within the first half of the exit span. And then how long this span really depends upon how much correction you're looking for. Typically these carriages are allowed to pivot only about 5 to 10°. If you want larger correction then you can make these fans longer. The main thing is that you need to make sure that the plane of motion of the carriage is perpendicular to the entry and exit span so that you can create a pure twist on these spans. And then as long as these rollers are moving in tandem or parallel to each other, then you will have the desired effect. They don't have to be on the same carriage. They can be on different carriages as long as we are able to move them parallel to each other. You can even have a process here. You don't really have to have just two rollers. You can have multiple rollers. So, it provides a lot of flexibility here. The guiding action is actually happening in the exit span. We don't want to install the sensor too far away or in the next span. This is mainly for control system purposes. and stability. When the web guide makes a corrective action, that action is not seen at the sensor immediately. So, if you're running really fast, you might get away with moving these sensors a little farther down. But if you're running slow, whenever this web guide moves here, you would see that motion if the sensor is as close to the exit roller as possible. If you install it here or here, especially when the web stops and there is a small error, the web guide would keep moving and that might cause the web to break or have unintended consequences. So, we don't want to have the sensor farther away or in an expand. And we don't even we don't also want to have a scenario where you have an angle that is not 90°. If you have a 90° wrap, you have twist. As soon as you introduce something which is deviating more from the 90° you start creating bending in the web. So these kind of bending is going to act as under steering the web. It's going to cause bending that's going to under steer the web and it also causes distortions and guide instability. So we don't really want to have any of these conditions. On the contrary, if you have a span exit span that is spread out like this, this is going to over steer the web, it's the bending effect that is causing that. And we really don't want to do that. So, ideal scenario would be to have a 90° wrap in and out. [Music] ## Related Products - Wide Web Guides - Low Profile Web Guides - Web guide mechanism - Web Guides **Tags:** web guide, web guide installation, web guiding system, web guiding, displacement guide, narrow web guides, Wide Web Guides, Low Profile Web Guides, Web guide mechanism, Web Guides --- ## About Roll-2-Roll Technologies Roll-2-Roll Technologies designs and manufactures patented fiber-optic web position sensors and advanced web guiding controllers — the precision measurement and control core of modern roll-to-roll manufacturing. Spun out of Oklahoma State University's Web Handling Research Center and trusted by Fortune 500 medical, battery, and nonwovens manufacturers, our patented sensors work without recalibration at ±0.1mm accuracy up to 760 mpm — typical customer outcomes are 50%+ less downtime and payback under six months. Headquartered in Stillwater, Oklahoma, our team of PhDs, controls engineers, and industry veterans extends the sensor + controller core into complete web guide systems including stepper-motor-based linear actuators (RLA, BLA, LHS). - Website: https://r2r.tech - Phone: +1 (888) 290-3215 - Email: sales@r2r.tech