July 2017 - Lägler North America

Big Machine Sanding Direction, Speed + Pressure

Sanding wood floors is a science. Knowing that science is what sets you apart from DIY homeowners who want to save a buck and try their luck.

In fact, when a lifestyle blogger reached out to us a few days ago wanting some tips for an article on “refurbishing” wood floors, this was our answer:
Hire a professional. Then we laid out some truth on what it takes to be good at sanding floors, how someone who is inexperienced is virtually certain
to jack up his/her floors. Hire. A. Professional.

That said, even pros aren’t gifted at birth with knowing the science it takes to perfect a floor. Learning is a process that never ends.

For example …

1. We see photos on Instagram everyday showing people running big machines. Some are moving left to right across the room. Some are moving right to left.
Some run parallel to the straight-laid boards, and others cut at a slight angle across them.

Do you know … What’s the best way to sand a wood floor: moving from left or right, and parallel or at an angle? What might be exceptions to the rules?

2.Your big machine has variable pressure settings. For the Lägler HUMMEL, there are three – coarse, middle and fine – that can be chosen by use of a simple
lever. Other big machine models have their own adjustment mechanisms.

Do you know … Which big machine pressure setting should you use for what situation, and when?

3.Then there’s speed. How slow or fast you walk when using the big machine relates to the pressure setting and abrasive grit you’re using. How hard or
soft the species of wood you’re sanding has an impact, too.

Do you know … How fast (or slow) should you dance with your big machine? And what speed with what grit abrasives?

Sanding Direction: Left to Right vs. Right to Left

The HUMMEL’s eight-inch sanding drum is positioned at the right edge of the machine. The lateral wheel that trails the drum always rolls on the freshly
sanded surface.

Because the drum is on the right side of the HUMMEL, the left wheel runs on whatever surface – sanded or not yet sanded – the left side of the HUMMEL passes
over. Forward and backward.

By sanding left to right across the field of the room, all wheels of the HUMMEL will run on the same sanded surface. The machine will be level and you’ll
get optimal flatness as a result, avoiding waves. This benefit carries out in a domino effect for each sanding step in the process.

The exception to the rule is in tight or awkward spaces where common sense tells you to throw a change-up.

Big Machine Sanding Angle

If you sand with the direction of straight-laid floor boards, you are maintaining what has happened to that floor over time. You’re giving it a new look,
no doubt. But the flatness …

When you sand at an angle, you are:

Cutting across imperfections from floor movement, damage and neglect
Avoiding the vibration of loose boards that cause chatter
Avoiding waves rolling down the length of the boards

Until recently, Lägler recommended in its sanding manual to sand at an angle except for the final pass.

When sanding at an angle, at first, the scratch pattern will be more noticeable than when you cut with the direction of the floor boards. But as you sand
with increasingly finer grits and, especially, if you use a quality multi-disc sander in the process, you will remove those scratches.

Lägler now recommends to sand at an angle for all passes with the big machine.

The exception to this rule is when dealing with cupped boards of a straight-laid floor. On the first run across the floor, knock those
edges down with a head-on attack. Then go to sanding at a slight angle.

Adjusting Big Machine Sanding Pressure

Sanding pressures with the big machine are tied to abrasive grits. The finer the grit, the less drum pressure you should use.

The wood species matters, too. Softer woods should be sanded with less pressure, so not to cut too deeply into the floor.

The chart above, from Lägler’s “Sanding of Wooden Floors” manual, lays out grits related to pressure settings. Clear cut. Common sense.

When you have an extra-rough floor or one that’s damaged or coated with a hundred years of nasty, get mean with that first run. If you’re using 16 grit,
you know it makes sense to put on the coarse drum pressure to make the most of it.

Big Machine Walking Speed

To minimize sanding marks and save time in the process, pace yourself. Not too fast, not too slow. No matter how many years you have at the lever, this
relationship has to move at a steady pace. Keep in mind the grit and drum pressure. Overall, consistency is king.

For softer species, a little quicker walking speed will keep you from cutting too deeply into the floor. Or maybe it’s just that you need a slower speed
for harder species. You’re the pro on the job. If you’re getting worse scratches than you want, change the music you’re groovin’ to and adjust your
dance moves.

Learn more about the fine details of floor sanding craftsmanship. Participate in Lägler’s one-day Premium Sanding Technology (PST^®) certification course.

And download the Lägler “Sanding of Wooden Floors” manual online. It’s free.

Abrasives: Cost Vs. Value of Quality

There are two approaches to floor sanding: guesswork and science.

Guesswork creates variables and challenges in sanding jobs that aren’t there. It causes the professional to change his or her approach from job to job,
species to species, and floor pattern to pattern. It produces results that vary.

The science of sanding is a proven process a professional can learn and use on each job, regardless of species, board widths, and installation pattern.
It produces consistent, quality results.

Quality is everything, if you’re trying to build a strong business on good work. That goes for your skills, machines, customer service, abrasives and the
other details. If you’re off-target in just one of those key areas, word on the street will bite you in the dust bag, whether you know it or not.

We talk about training and boosting your skills often on this blog, especially about Lägler’s Premium Sanding Technology (PST) class. Of course, we get into machine quality every day, too, talking about the standards Lägler holds itself to or just by posting photos of
Lägler’s craftsmen on Instagram quietly going about the business of hand-building and testing its machines.

It’s time to talk more about the ripple effect of choosing quality, especially with abrasives.

Cost vs. Value of Quality

Quality abrasives play a super-important role. Like with anything, you get what you pay for. Pay for cheap products, get cheap results.

You probably tell homeowners that. And you often see the problems caused by hacks, right? A homeowner calls you in to fix the disaster a “professional”
made of their floor. It was the low bidder they’d hired for the initial job, focusing only on the short-term pain of the money they were spending.
Now they are losing sleep, stressing the expense and headaches of the shoddy work they got from the contractor from hell.

They are painfully figuring out they’ve got to pay you what they should have stepped up to pay in the first place, just to fix the mess. That’s on top
of the money they already spent and the worry it caused them. Cheap quickly turned into way more expensive.

The same goes for any business that relies on quality ingredients to put out quality products or services it sells. A restaurant that goes cheap to save
a buck is short-sighted. It loses business in the long run because it’s worried about the cost of, say, a case of burger patties. The owner of that
restaurant probably isn’t connecting bad Yelp reviews to one purchase like which meat to buy.

But it isn’t just the meat. It’s the domino effect of that mindset that leads to going cheap on one thing after another. That restaurant owner doesn’t
invest in the other ingredients, either. Or replace the dirty or torn seats in the joint, or keep its restrooms clean, or care all that much when a
jaded employee doesn’t give customers a hello or smile or quality experience. Downward spiral.

For a true flooring pro – a craftsman – pride in quality work is at the top of the list. The good kind of word on the street makes the rounds and builds
the business like it’s got its own motor. Do good work, get good work.

Floor Sanding Abrasives: The Nitty Gritty

The materials used in making abrasives affect sanding rates and how many square feet of life a professional gets out of them. Inexpensively produced abrasives
have shorter service life and need more frequent changing. The minerals used in inexpensive abrasives do not perform as aggressively, leading to more
time spent in the sanding process.

In the end, the additional costs of buying, storing, and transporting a larger quantity of lower-quality abrasives, plus having to spend more time sanding
with them makes investing in quality upfront a better value. (Sounds like that thrifty homeowner in the example above, right?)

In fact, the science of sanding means little without using the right abrasives for the right situations. A highly skilled race-car driver who has a fine-tuned
car can do little with it if the wrong tires are on it.

For wood floor sanding abrasives, the minerals, underlayment and adhesive are difference-makers. The types of underlayment (paper or cloth) and minerals
(silicon carbide, ceramic, aluminum oxide, and zirconia) needed depend on the intended use.

Grit Sequence for Success

Grit sequence is a key factor in the floor sanding process. It’s essential to follow the steps, like shifting properly through a race car’s gears. The
driver doesn’t get ahead by skipping gears. Instead, he bogs down his momentum.

Unlike in a car, proper grit sequence allows for skipping one grit, but only one. If a professional jumps two or more grits in the sequence, the scratches
from the previous grit will not be adequately removed. It will cost more effort, time, and abrasives to redo the work.

The first sanding step should be done with as coarse a grit as necessary, but as fine a grit as possible. That’s where the variable enters this science
of sanding. The professional must use his experience to recognize if a floor’s condition calls for an especially coarse grit to start.

For example, if it shows severe cupping or is coated with thick lacquer. The starting grit will help to determine the ending grit to be used. Everything
in between follows the steps of the process.

The science of sanding can be learned. A sanding professional can bank on its predictable, craftsman-quality results. No guesswork needed. Clients might
think it’s magic. It’s OK to leave them guessing.

The Bottom Line

Quality customers know when they are dealing with quality professionals. When they hire someone to sand and refinish their floor, they are investing a
good chunk into their home. They want to feel great about that. They want to know what they get back for their trust in you will be worth a grit when
the job is done.

Choosing quality is everything.

Learn more about the best ways to boost your floor sanding game. Learn it from Karl Lägler, the man who wrote the book on that game, by downloading the
free “Sanding of Wooden Floors” manual online from Lägler.