Mosaics & Glass Tile

[John Bridge]

The original post is at: http://johnbridge.com/vbulletin/showthread.php?t=18797 -- J.B.

I think you guys may have gotten into a little trouble here... That means that whatever I suggest can't be any worse, right?

Here is how I've managed to get a similar mosaic done. I use clear shelf liner film (the sticky kind that around here goes under the brand of Mac Tack). First tape your drawing over a good solid piece of plywood slightly larger than your artwork. You will need a second piece of plywood of the same size to help you turn the piece over later on. Then take the liner film, place it over the artwork and staple it at the edges only. The Nac Tack goes upside down (sticky side facing upwards,) but do not peel backing paper yet. Make sure that the film is bigger than your drawing by 1-2" on all sides. Now peel off the paper to expose the sticky surface.

Hint: If the mosaic is large, break it down into smaller panels; say 12"x12". Work in small scale and assemble the units later to create your full size mosaic piece.

Now you have a clear sticky surface over your drawing that you can use to start assembling your mosaic right side up. As you place the tiles, they will temporarily be held in place. If you need to remove a tile, no problem, just stick another one in its place. If the tiles are of different thickness, don't worry, we will address this later. Your only concern is to finish the job before the sticky surface dries out completely (my experience is a few days).

After the mosaic assembly is complete, take another piece of shelf liner and apply it to the surface of the tile. Carefully pat it down to catch as much of the tile surface as possible. A sponge or brush may help. Seal the edges of the exposed shelf liner to help stabilize the loose mosaic pieces. At this point you can cut or remove the staples holding down your shelf liner.

Sandwich the mosaic with the second piece of plywood and secure it so that it cannot come undone. You can use duck tape, spring clamps, etc. to hold the two pieces together. You are going to flip the entire panel over, so you need to make sure that the mosaic does not slide and fall out while you do this.

Once you flip the panel over you can gently remove the plywood and expose the underside of the mosaic. Carefully break away any staples or tape that you used to secure the film so that it does not disturb your finished work. If all goes well your mosaic will be facing upside down flat on the plywood, with all uneven surfaces facing you!

Now here comes the trickier part. You need to peel away the old shelf liner to expose the back side of the mosaic panel. The glue of the old shelf liner should have dried a bit and will detach more easily than the freshly applied liner. It is likely that the two pieces of shelf liner have stuck to each other at the edges, so carefully cut away around the edge of the film to expose only the back of the mosaic.

The next step is a matter of judgment. Your mosaic is upside down, held together by shelf liner on the good surface. You can follow standard paper faced mosaic installation methods for the final installation. Handle the mosaic sheet very gently, as the shelf liner does not hold the mosaic pieces as securely as mosaic paper and gum arabic.

A second, less conventional method is to apply fiberglass tape (wide drywall tape or even fiberglass moquito netting) to the back of the mosaic and then apply mortar so as to create a flat surface. The fiberglass tape will help keep the assembly together later on. Allow the mortar to cure until it can be gently handled (24 hours). Again use the plywood to turn the mosaic over, gently peel the shelf liner and clean away any excess mortar from the surface of your work (it should still be wet enough). Once completely cured (minimum days), your mosaic panel can be treated like a large tile that is installed with convetional thinset methods. I find this works particularly well whith 12" mosaic panels.

I think I've given away all my secrets.

Kim
__________________
Kim Hauner
Technical Services
Interstyle Ceramic & Glass ltd.
Canada
http://www.interstyle.ca/

[John Bridge]

From Kim Hauner of Interstyle, Vancouver, B.C.


Hi there. I hope you don't mind if I join in. This is Kim Hauner of Interstyle. The tile you are installing is not manufactured by us, but 4"x4" glass tile is one of our specialties.

In a steam room you need to make sure that you have a waterproof membrane. You also want to make sure you have good separation between the tile and substrate. You can accomplish both by installing a crack suppression membrane. We recommend a peel and stick membrane such as Protecto Wrap, Mapei or N.A.P. Laticrete also suggests their waterproofing system as an option, although we have not tested it as a crack suppression membrane. Definitely do not apply the tile directly to the substrate.

Choose a white, fast setting, flexible thinset. The theory is that you need the greatest flexibility in the thinset because the glass tile is very inflexible. This will allow any movement in the installation to be absorbed in the crack suppression membrane and thinset. A fast setting thinset is desirable because the thinset will be applied between two non-permeable surfaces (glass and crack suppression membrane) and you may end up with some picture framing behind the glass if the thinset dries around the edges but not in the center of the tile. We recommend Grani-Rapid by Mapei. Be sure to use white thinset so that the color of the glass is not altered.

Use the smallest amount of thinset possible. Spread the thinset with a notched trowel (a 3/16th V notch will do) and flatten out the ridges with the flat side of the trowel (being careful not to remove thinset in the process). With tiles 4"x4" or larger we recommend back buttering the back of the tiles. All this will prevent the appearance of ridges or discoloration to show through the surface of the glass.

I prefer to apply caulking to the inside corners prior to grouting. That way you will end up with the most flexible joints possible while hiding the ugly surface application of silicone. Choose a mould resistant caulk.

Select the most flexible grout possible. Although the mould resistant properties of epoxy grout are very appealing, they are generally considered inflexible. For that reason we prefer a traditional polymer-modified, mould resistant grout that is carefully cured as per manufacturer's instructions.

Cutting glass tile can be a challenge using traditional tools. You may score and break a 4"x4" tile using a glass cutter and a ruler. Do not use a tile cutter because the wheels are not angled property to score glass.

An easier method is to use a wet saw with a proper blade for cutting glass. Standard blades used for cutting ceramic tiles, even continuous rim porcelain blades, are too coarse for glass and will rip out little chunks of color from the back of the tile. A better blade is a lapidary blade that uses very fine diamonds, or better yet, you can purchase a very inexpensive electroplated diamond blade. Electroplated blades are very thin and have very fine industrial diamonds plated to the outside of the blade. This prevents most of the chipping associated with ceramic blades. Be sure to cool the blade with water, or turpentine and water that will extend the life of the blade.

Cutting or coring holes can be accomplished in one of two ways. A nipper can be used to trim larger holes. Don't be greedy and nip little bits at a time. A glass coring bit is the preferred method. A glass coring bit is made with very fine diamonds plated to the outside of the bit. Be sure to cool the bit by using a water dam filled with water or turpentine and water.

One more hint about installing fixtures and anchors. Always anchor any supports directly to the structure and do not apply any pressure to the substrate or glass tile. It is best to drill an oversize hole on the glass and fill it with caulking. This will prevent any pressure to build up on the surface of the glass that may cause it to break later.

Sorry to be so long winded. I hope this is useful to you.
Today 08:07 AM

[Mike2]

Here is a link to a glass tile Installation Guide from Oceanside. http://www.glasstile.com/OGT-Install...glish_2013.pdf It does quite a nice job of explaining the key steps of a glass tile installation, including both setting and grouting. Large format tiles are covered as well as paper faced mosaics.


edit: Here's a link to Oceanside's installation resources. There's great info here about how to install glass tile.


Other Methods.
Additionally, here are links to some other discussions of setting glass tile, including the One-Step method which uses grout.

Laticrete's One-Step Method:

http://johnbridge.com/vbulletin/showthread.php?p=382081

Laticrete's latest data sheet on installing glass mosaics.

edit: Laticrete now has powder grout colorants that can be added to color their thinsets. It's best to go to their site to get the latest information. Here's a link to their data sheet that currently has information about coloring their glass tile adhesive.

A Modified One-Step Method: Read down through Post #7.

http://www.johnbridge.com/vbulletin/...2&page=1&pp=15

Are These Methods Supported By Your Tile's Manufacturer?

These alternate methods can offer a time-saving departure from the traditional method of thin-setting, then grouting. And they also can eliminate the problem of the look of dried thin-set encroaching through a different colored grout. However, because glass tiles can vary in both thickness and some technical properties, make sure your manufacturer has approved the method for the tiles you are using. Different types of glass will have different setting requirements.