Repairing plaster before tiling

currants

I want to tile 3.5m2 in my kitchen. When I took the old tiles off lots of plaster came away from about half the area. I think its down to the scratch coat as I can see vertical wavy lines. The rest of the plaster looks ok, just needs the old tile adhesive scraping off.
I was thinking of using Jetcem quick set patching plaster to level off the wall and patch up missing plaster before tiling over. Any advice on using this or is there anything better and easier to use out there? Do I need to prime it with anything else before tiling onto the wall?

My tiles are quite big so I know the patching will need to be very level and I'll have the spirit level at the ready, I've never plastered before but have done a lot of filling and am quite good at getting it smooth and level.

Sleeper12

The wavey lines are the tile adhesive. This is how you apply tile adhesive. Blobs of adhesive is the wrong way. It dramatically increases the chances cracking a tile if it needs to be drilled at a later stage

Bonding to fill in the holes & then skim coat. If the wall isn't level then the tiles won't be level

currants

Thanks Sleepy but I don't think the wavy lines are tile adhesive as they were underneath the plaster, these wavy lanes are more elongated S shape about 12-14 inches long that are cut into the wall. I understand this is scratch coat?

I know what you mean about the tile adhesive lines, there's some of that still on the surviving plaster too and that is what I'm going to scrape off.

So really there are 3 different surfaces on the wall- elongated SS's marked into grey coating, thin skin of greyish-whitish plaster and then bits of straight lines of old tile adhesive that match the small size tiles that were up there.

Bonzo Delaney

Clean off all the tile adhesive first. Hack off any loose skim coat around the area knock on the wall to check for a hollow sound this means the skim coat is loose.
Give the area a coat of pva polybond mixed 3:1
Let it dry to tacky 20min Then fill/ skim in the area
Dont use your level youll ruin it with plaster use a timber straight edge/feathered edge usally a straight lenght of bullnose skirting works fine
let set till it turns white /day or two depending on how much was put on, then tile

agusta

With a hammer and 1" old wood chisel take off the rest of the skim coat.if half the skim coat is already off the other half should remove quite easily.The cement render scratch coat is the most ideal surface to tile onto.skimcoat is not.Prime surface with bal apd primer or similar

currants

Thanks again folks, I'm going to get the rest of that skim off and get that primer. Hope to tile it next weekend so I'll report back.