Complete Novice hoping to tile window sill with slate

[Seagull27]

Hi all

I am planning on tiling my window will with 5 slate tiles. They are around 8mm thick. Here are some photos of the substrate:

[Please PM. See Post #2]

Money is mega tight so I am trying to do it as cheaply as possible. I've been told I need to seal the substrate and was planning on using this:

[See Post #2]

And for adhesive I was planning on using this:

[See Post #2]

My questions are:

1. Do I definitely need a primer if using the above mortar for adhesive? The window sill had tiles on it before that we removed, just in case that makes any difference.
2. Will both of those products do the job ok?
3. If it is OK to use the mortar, what's the minimum thickness I can get away with? The thinner the better for me....
4. I want the gaps between the tiles to be around match stick width. So I need to use grout or can I use the quick st mortar.
5. I have not sealed the top side of the tiles because I prefer the unfinished look. Is this a silly idea for slate? Any tips on keep them clean while fitting them, grouting, etc.?

Any tips or other advice on these questions and/or anything else would be appreciated massively and of great help for my first ever stab at tiling!

Cheers

 

[Seagull27]

Unfortunately I don't have enough privileges to post a picture, so if anyone is able to help and needs to see the substrate, please PM me.

I'm not allowed to post URLs either....

So for the primer I plan to use, please Google: SCREWFIX MAPEI PLASTER PRIMER

And for the adhesive / mortar, please Google: WICKES QUICK SET MORTAR 2KG

Cheers

 

[Time's Ran Out]

Just mix up some sand/cement 2:1/3:1 use that to fix tiles with and your matchstick joints and grout with same mix.
When dry, clean off with a bit of cement remover and clean water.

Cheap as chips!

 

[Seagull27]

Many thanks for the response and help....

Since posting though, my other half - who is forever calling me a procrastinator (probably quite fairly) - took a trip to Wickes/Screwfix and has bought the Mapei Plaster Primer and Wickes Quick Set Mortar.

Grout we already have a bit of. I was just asking whether I can use the mortar because I thought it might be easier (plus it might turn out that I prefer the colour of the mortar).

So I guess most of my questions above still remain, with the odd slight tweak...:

1. Now that I have the primer I might as well use it, although I guess I could return it if it won't make any difference whether I use it or not. Is it possible it could actually cause more problems than it solves?
2. If it is OK to use the mortar, what's the minimum thickness I can get away with? The thinner the better for me....
3. Do I need to use grout or can I use the quick set mortar if I prefer the colour and/or it is easier quicker?


Thanks for the tip regarding cleaning the top of the unsealed slate. I was going to use some masking tape around the edges... Is that overkill/stupid?

Cheers