Primer for mosaic

[88v8]

A local craft group is making a large mosaic using bits of tiles on three sheets of 6x2 ext ply.
Using PVA to stick the tesserae.

I think the ply should be primed with PVA or the mosaic will eventually fall off.

What do you think?

 

[Deleted member 174758]

I think you are right. My parents used to do mosaic work decades ago and I recall my old man keying the surface of picture surrounds either with very cosrse sandpaper (e.g. P40 grit) or by cross hatching with a Stanley knife. Then surface was then sealed with dilute PVA (probably 4:1 or 5:1 PVA to water).

 

[Wayners]

You buy the correct adhesive for the ply then read what is the recommended preparation.
Each manufacture will recommend products to be used.
If unsure phone the technical helpline for the product.