Hardwood Floors April/May 2024

By Russ Watts

One could hardly argue that chatter isn’t a fitting term for all unwanted features of the big machine’s work. It normally is identified as a repeating series of marks, usually transecting the wood’s grain at a width that is often more or less the width of the sanding drum that was used. Most would agree what chatter looks like, but very few take the time to investigate the root cause of why these marks are being left behind. I have all-too-often witnessed big machines in service centers with tags on them that read things such as “leaves chatter” or maybe just “chatter.” I wonder if the conversation between the mechanic and the service center begins and ends with “my machine is leaving chatter,” without any further questions. Not asking for enough information can be an easy habit to get into. Letting “chatter” be an end-all to the conversation is an example of a bad habit. Maybe it’s because the term is just so common in our industry that many believe they know what chatter is and let it go without further thought. We need to gain the understanding that there is a glaring flaw in the term “chatter,” and when it is left on its own, it lacks a true landing spot when we break down what a floor sanding job really is.

To get there, we must first recognize there are two central goals in floor sanding: SAND JOB TOPOGRAPHY – Referring to the SHAPE of the floor’s surface as a result of the sanding that was done: Is it flat or something other? In wood floor sanding, we aim to get it FLAT. SAND JOB COMPLEXION – Referring to the wood’s ability to express its unique character after sanding: Is it free of visible scratch pattern signatures that otherwise would interfere with its visual value. (This typically has nothing to do with how flat the floor surface is.) In wood floor sanding, we aim for a clean complexion. Understanding the concepts of sand job topography and sand job complexion as separate criteria proves to be key in navigating the causes and cures of bad results. Once this approach is applied to a complaint of chatter, it doesn’t take long to realize that problems left behind from big machine use easily can fall into either category. WHEN DIAGNOSING “CHATTER,” YOU ARE FACED WITH TWO QUESTIONS: Is the problem a matter of sand job topography? (Did the big machine’s work actually dig in repeatedly and deform a surface that is supposed to be flat)? or… Is the problem a matter of sand job complexion? (Is the surface flat as one would expect, but the big machine’s scratch pattern features visible bars that transect the boards)?

This is a critical diagnostic step, since the potential causes for each involve lists of usual suspects that are quite different from each other. To understand how all of this works and fits together is to understand how chatter is truly non-specific to either category. From here, we now can begin to ask for more information.

the magazine of the national wood flooring association

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