Page 20 - Demo

20|November 2019
Stone Restoration and
Maintenance Corner
Laboring Lippage
WEhave discussed lippage before, but it is such a reoccurring issue that I thought revis- iting the topic would be of value. Lippage, not to be confused with the back-talk from your significant other, or quite possibly even your mom, lol, is the height dif- ference between one tile
and next.
Even with the high tech tile setting systems of today, to install a totally lippage-free floor is practi- cally impossible. Of course, having proper grout width helps with the precision of the install. Grout lines that are too wide can increase the margin of error for lip- page. Remember, for mar- ble and other dimensional stone, the grout lines should typically be no larger than 1/8” or even 1/16”. Wide grout lines normally re- quire the addition of sand for strength and stability too, and we all know that is a no-no, for most finished stone installations.
Slippery rock Gazette
Bob Murrell
M3 Technologies
Photos by Bob Murrell
People, meaning custom- ers, who do not know the significance of lippage, will tell you there is no height difference in their floor installation. They are not trying to deceive you, they honestly just don’t know what to look for. Of course, neither do some general contractors. Most anyone, who has never had to remove lippage, doesn’t understand the significance of it.
As restoration profession- als, we know that irritating sound from diamonds going clackety-clack on the un- even tiles. We know that dreaded sound means more work and potentially much more work. It also means more costs, both to you and therefore the customer, too. Lippage is typically the most expensive step in the restoration process, not to mention the fact that it also
Moderate lippage on a limestone floor.
Severe lippage on a marble floor.
means there are now more steps in the process as well. Breaking out the metal bond diamonds is always a major commitment. Depending on the severity of the lippage, it will deter- mine the step at which you start. Trust me, if you have severe lippage, starting at a 70g metal bond diamond will make for slow going. For example, let’s say you go ahead and go for the gusto and start with a 50 grit or somewhere close to that. Starting with a 50 grit or coarser metal means that you will probably need to go with either a 70 grit metal or 50 grit transition resin diamond next. So you easily end up doing two steps before you ever reach 100 grit or 120 grit. Hence the reason for both the
added time and cost.
There are ways to cheat
the lippage removal system in certain situations and I’ll discuss this in a moment. The terms picture framing or widow pane come to mind for those who have experience with lippage removal. This is especially true for darker floors and definitely most black floors. The lighter colored stones are better with regards to
disguising and blending the picture framing. You see, the high spots are not necessarily the main prob- lem with lippage. The low spots typically remain in the original finished con- dition, meaning they never received wear like the sur- rounding surface. These low spots, which show up as the picture framing areas, can stick out like a sore thumb.
If you have ever had the request to convert a previ- ously polished marble floor to a honed floor, lippage re- ally becomes an issue. The picture framing just can’t be blended or matched like when polishing. This sticks out so bad that contractors will try anything to get rid of it, even turning to the use of strong acids to etch and remove the polish in these low areas. This operation of going from polished to honed can be very tedious. It is best to go ahead and remove the majority of lip- page, through grinding, in this scenario.
Deciding on the type of metal bond diamond to use in the initial heavy grinding of the lippage removal pro- cess can be a key compo- nent as to how much work you will have to commit to.
There are many diamonds that can accomplish this task, but doing it with as little of an invasive scratch pattern is the trick. You see, some metal bond diamonds can leave behind a very aggressive scratch pattern. That is why you probably wouldn’t want to use a 16
grit or 24 grit concrete-type diamond. These super ag- gressive metal bond dia- monds are used for coatings removal or heavy rectifying situations where the scratch pattern left behind is not consequential.
Please turn to page 21
Severe lippage removal using a hand tool with ELF5 Flexible Metal 40 grit.
Restored polished marble, honed in place.