Good morning cynthiamatherne,
Welcome to the community, lets have that undesirable grout off your slate tiles.
The good thing is that even though you have actually dried grout around your new backsplash, you can easily remove it it with some simple products we sell on our tile aisle.
I am assuming we have been talking about pre-mixed or polymer-based (bagged) grout, and never which will be an alternative chemical makeup and needs a to take it off.
You will have to get the grout off, and do it properly so as not to discolor or destroy the record tiles. For that reason, buying a grout haze cleaner will get the job done and never harm your tiles. Shown the following, this is the most sensible thing that will lose grout haze, and any large accumulations of grout.
As previously mentioned above inside image, you will have to utilize a plastic bristle brush nor make use of any such thing harsh like steel wool. The cleaner alongside the brush plus some good elbow grease should certainly take care of the unwanted grout in your record tiles. make use of the grout haze remover and brush in a tiny (typically 3' x 3') location. You may have to reapply the haze remover several time over certain areas as well as softly scrape any large accumulations of dried grout. Always remember if you should be doing any scraping to take action carefully in order not to harm the tile it self.
At the end of the afternoon, with using the materials shown above, your tiles should shine through with no extortionate grout left on backsplash.
But if the grout haze remover would not satisfy your objectives therefore'd like something more harder on removing grout safely, I would suggest utilizing sulfamic acid. This particular safe-to-use cleaner goes somewhat much deeper when planning on taking down any mortar/dirt/grout compared to grout haze remover. Do not get myself wrong.grout haze remover works perfect for many grout elimination programs, but utilizing sulfamic acid eliminates everything.
And that is virtually it! No matter what long the grout has set, these products mentioned above should get the record tiles back again to the way they looked before.
Do not forget to use aon your backsplash tiles and grout a while later assuring you should have years of security.