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How to Test Floor Flatness with a Big Machine

Besides getting awesome Instagram shots on the job, of course, getting the floor flat is the most important part of sanding wood floors.

But that’s harder to get just right if you don’t take a few minutes to figure out the flatness situation before you get started. You’ve got to know what’s
out of whack with the floor so you can game plan how to make it the level of flat you – and the homeowner — want.

We know you know the feel of unevenness when you’re sanding, and sometimes it’s easy enough to see. But taking some minutes to mark out the uneven spots
will make the job easier.

Here’s a simple flatness test you can do with your big machine, before you start sanding.

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Check Floor Flatness Using Your Drum Lever

Use these quick and easy steps to help you mark out high and low spots of uneven wood flooring. It will make those areas easier to see when you’re sanding.

1. Put a fine-grit, used abrasive belt on your drum.

2. Make sure your machine is turned off.

3. Lower the drum to the floor.

4. Roll the big machine at an angle across the boards, paying attention to the drum lever’s movement. If the lever moves up, the floor is rising. If it
moves down, the floor is sloping downward.

5. When the drum lever moves more than a little bit up or down, mark the area as high or low with a pencil.

If you do that to the whole room, you’ll be able to step back when you’re done marking out the spots and see the game plan laid out in front of you. High
here, low there. Low right over here, high over there.

These kinds of prep steps save you hassles later in the process. By doing everything you can to knock the floor flat upfront with your big machine, the
fine sanding steps will go much better. If not, the unevenness will continue through each step, making you have to work harder all the along the way.

Free Floor Sanding Manual from Lägler

Learn more about work-smart sanding techniques in Lägler’s “Sanding of Wooden Floors” manual. Download the full manual for free at

Want a chance to improve on a practice floor with Lägler at your side? Call us to set a date for you and your crew to get Lägler certified: 800-848-6635

Learn more about Lägler Premium Sanding Technology (PST®) training on
our blog, too.

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