Paint

[antifoul2020]

What type of paint should I use
When applying a backing board

 

[Jaco]

What is the project or what are you using the backing board for?

 

[RogerJSJ]

I've used the spray paint (below from Amazon) onto hardboard as a backing on a few projects and it looks OK.​

Wilsons Direct 151 Multi Purpose Spray Paint 400ml Black Matt​

 

[scrimper]

Without knowing about the project it's difficult to say but have you considered using different coloured woods? For example a light wood for the work and a dark one for the backing as shown in my butterfly bracket below.
As Roger suggests spray paint is probably the best but you could also use the cheaper acrylic paint available widely at little cost i.e. B & M stores.

 

[antifoul2020]

What is the project or what are you using the backing board for?

 

[scrimper]

Very nicely cut. Why not use a dark stain on your backing piece. Would look more natural than paint?

 

[antifoul2020]

Stain is the way i will go
Help much appreciated lads