white ink not adhering

[prof-potts]

Hi, I'm having instrument faces printed and we have had an issue recently (new print company using roland LEF12) where white graphics printed to matt black faces are "pinging" off if touched by screw head or rotary file (to widen screw holes in dial face)
To be clear, the entire graphic part eg a zero in a figure "20" will ping off, not rip or crack but literally ping off!
We are using an off the shelf good quality auto paint to prepare the dials and the finish is flat and clean (straight from the drying room)

Our previous printer had the same issue and said it was down to the white ink not being "cured" enough but he gave no further comment.

I would like to go back to my current printer with a solution so my question is;
What kind of base paint should I be optimally using to get the best adhesion from the white ink? (matt black)
Is there anything the printer can do re setting his printer for "better curing"?

thanks in advance

[mrtn]

Put “primer” in search box and read up. All good info.

Flaking when drilling/milling a UV-printed material is a well known issue regardless of printer/ink.

Also you shouldn’t print on freshly painted surfaces without degassing first. It may take a long time depending on the paint and material type. Hell, you shouldnt even vinyl wrap a brand new car. The UV-ink will also react with the paint and cause unwanted result.