Is there a spray that prevents paint from sticking?

[Juss1]

I'm doing a cnc project and want to paint it all of the non carved parts.  There are lots of tiny spots and I'm worried I'll accidentally get paints in the carved section.  I was hoping to coat everything with something that won't allow paint to stick and then drum sand the piece so the carved section only has the sprayed solution.  Hope that made sense.

[packerguy®]

I'm doing a cnc project and want to paint it all of the non carved parts.  There are lots of tiny spots and I'm worried I'll accidentally get paints in the carved section.  I was hoping to coat everything with something that won't allow paint to stick and then drum sand the piece so the carved section only has the sprayed solution.  Hope that made sense.

Why not just paint it then do the CNC?

[Juss1]

Why not just paint it then do the CNC?

It's not 1 single color.  Different parts of the piece will have different colors

[jteneyck]

It's not 1 single color.  Different parts of the piece will have different colors

Would the film people use work?  Some folks even use cheap shelf liner product.  I'm not sure I understand your work sequence, however, so maybe this isn't a solution.  

John

[Juss1]

Here is what I want to carve.  Bought the vector file from etsy.  As you can see it has several colors.  An idea just came to me.  I'm going to do a profile toolpath probably 1/16" deep.  What if I initially just carve it 1/32" deep, paint it and then carve it again another 1/32" which would clean up any spill on the carved portions.  Would referencing off the dog holes be sufficient enough?

[Rob Young]

I'm doing a cnc project and want to paint it all of the non carved parts.  There are lots of tiny spots and I'm worried I'll accidentally get paints in the carved section.  I was hoping to coat everything with something that won't allow paint to stick and then drum sand the piece so the carved section only has the sprayed solution.  Hope that made sense.

Depends on the wood. Most of the CNC groups recommend sealing the wood with shellac or lacquer. Then sanding and applying Oramask (forget the exact part number 4-something-something I think). Then mill, re-seal the freshly milled portion and paint the cavities. Remove Oramask and top-coat to seal.

If you want the background a color, consider painting after sealing then Oramask then milling.

Open grain woods like oak or ash are going to be very difficult to keep paints out of the pores.

Nearly all the small signs I've done for people, I used MDF. Sealed it well then spray painted the background and carefully painted in the letters.

Example (close up you can see a few paint defects, but at 3 ft, looks fine) :