Thanks for your responses. :) It's a gypcrete floor underlayment. When you say not to mix the two together, do you mean not to mix together dry and then with water in same batch? Sorry, I didn't intend to say that, if that was what it sounded like I was asking. By "mix and match", I meant would it be alright to do one section of floor with one mortar. And then when I run out of that one, can I finish off the floor with the other mortar? I mainly had my doubts about using the Marble/Granite mortar for my glazed ceramic tile, but the Custom Products website said that it was fine for ceramic tiles, and particularly good for ones larger than 12 x 12". The tiles we're laying are 16 x 16". Out of curiosity, what does "medium bed" mean? Have a good evening and thanks again.

What you're describing is the indirect method of mosaic. I've used two methods, both with mixed results. On this garden pop I made, I used clear contact paper, sticky side up with the heart pattern underneath, taped to the bottom of a stepping stone mold. I then placed the tiles face down onto the contact paper and poured the mortar over it. Let it dry for a day or two before unmolding it. If cured properly for that period of time, the mortar is still soft enough to be able to clean the surface with a damp sponge and get a nice smooth finish. You can mix a little extra mortar and spread it over the top if you have gaps to fill in. Cure for another week or so before actually using the item. On the little owl below, I used brown paper made specifically for indirect mosaics. I ran it through my printer to print the pattern of the owl on the paper (in reverse). I then used a mix of 50/50 Elmers glue and water to adhere each tile face down on the paper, being careful to use the right amount of glue. Too little, the tiles won't stick well enough for the rest of the process. Too much, and you can't pull the paper off to save your life. Let the tiles on the paper dry completely. I then used a v-noch trowel to spread the thinset over my concrete base and carefully pressed the owl onto it, paper side up. To get the paper off, you use a wet sponge to soak the paper and it will peel off. As for when, I've tried two ways, both letting the thinset dry for a good day before I try taking the paper off, and taking it off while the thinset is still moist. In the latter, you have to be very careful not to shift the tiles while you're trying to get the paper off. You also have to be careful not to use so much water soaking the paper that you dilute the thinset underneath. If you do take the paper off while the thinset is wet, you would be able to add tiles as you've mentioned. However, I would not try that with contact paper. Contact paper is way too sticky. You would never be able to pull it off the tiles while the thinset is wet. I'm not entirely crazy about the indrect method. I have spent a ton of time on pieces that get ruined because the tiles shifted when I turned them onto my piece. I had to throw one away because I forgot to reverse the pattern and it mattered (it was a word!). I've had tiles pull off the piece when I've tried to pull off the paper. Then I've had pieces that just looked really horrible, and I didn't notice because I had been working with the piece upside-down. That said, I don't NOT use it. Honestly, every time I make one of these owls, it sells almost instantly. And making the stepping stones using the first method I described is really fun. It is a good method to use if you don't want to have to cover the entire piece with tiles, as the concrete fills in the gaps when you pour it. Of course, it only works when you're pouring concrete into a mold. If you want to put a piece on something already made, like a rock, I suggest the brown paper method, not the contact paper method you're describing. What I haven't tried, that SILVAMAE uses a lot is mosaic on fiberglass mesh. I am very interested in trying it as you can still mosaic on top of a pattern, but it doesn't have to be reversed, and you can lay your tiles down on the piece without having to worry about getting the mesh off the tiles. It just gets mosaiced into the piece. I just haven't found the time to give it a try yet.

ladyronnie - in regards to the curing - I'm still a beginner at working with concrete, so I've been following the directions in my Sherri Warner Hunter books....she mentions that concrete is fully cured after 28 days. And the first week is the most important - you keep the piece damp by misting and/or keeping it covered (I do both). It needs the moisture for the hydration process to take place, and for the piece to harden and strengthen. I've been following this process pretty faithfully. Although on my smaller pieces - the mushrooms - I only waited 2 weeks. I know there are differing opinions on this, though - and like I said, I'm a beginner! oh - and on small pieces - I got a medium size syrofoam cooler (thrift store, of course) and put the items in that, mist them really good, put a wet towel over them, put the lid on the cooler - and they stay nice and moist and you don't have to worry about misting so much! I've also read that you can just leave the item immersed in a bucket of water, too! maybe klinger will chime in here....she's got a lot of experience at this.

Annie- I did it on mesh because I hadnt tried it before and yes because it was so big. Hazie- the mannequin...oh man I am not ready for her yet...maybe after the holidays!!! (another great excuse not to start her cuz Im scared!!!) shrty- I can always use another Mom!!!! Grouting tomorrow night and will post pics then!!! Tomorrow I am doing a "how to make a stepping stone using the reverse method" get together with my MIL and her friend. So I wont get to grout till evening.