V Cutting Tape

[Leadhead]

Yes but, this assumes that you require a natural colour surface. As my conversation with Boyan above. I need a painted surface, which is another ballgame. Currently my method is to paint or spray my base surface (Z,0 surface) then use industrial strength iron-on film over that. A good initial surface is required and a well dried polymer based paint is imperative for good film adhesion. I cut through for my lowest contour first. Iron back the edges to ensure a seal against the painted edge. Then paint or airbrush in the cut. If going for three or more colours, then I repeat the iron on film process as required. (Find a small triangular model film covering iron is very useful.)
I have tried cutting the surface back, as you suggest, and rubber rollering the topcoat. Results where not good.

[EddyCurrent]

You could use laminations.
Layer1 would be your top colour
Layer2 would be your cut layer, revealed by the cutting tool.
Layer3 would be the unseen backing layer.

Pieces of different colour could be positioned in layer2 so that many colours would be revealed after cutting.
Of course that would take planning but the machine could cut those out to fit like a mosaic.

Some type of plastic would be ideal for Layer2 or possibly thin wood that had been fully saturated right through with colour.

[Leadhead]

Problem with solid wood or MDF is that the edge of that laminate has to be painted. Also it would seem to assume that the colour differentiation was on a common x,y (lamination) level. 3D colour changes would be inefficient at best I think. Unless you have a way please?

[magicniner]

This is about paint!
You need to paint the top surface with a paint which is resistant to the solvent in the paint for the fill.
If you cannot do this then the solution (no pun intended) is not what you would like it to be.

[Leadhead]

The polymer base paint I currently use is achieving this. The pita is keeping the film attached to the edges after the shearing action of the cutters. I have it sussed it 95% with the iron on film but my original search request was for a better film to give 100% adhesion and still be removable. I do have that workable compromise currently and with due diligence it is giving me a result. Simply seeking either a better film or method.

[phill05]

The polymer base paint I currently use is achieving this. The pita is keeping the film attached to the edges after the shearing action of the cutters. Simply seeking either a better film or method.

Only just come across this could a change of cutter help have you tried a down cut?

Phill

[Leadhead]

This application is for a "V" cutting bit. Not sure if there is a downcutting option. I normally use downcutters for pocketing.

[Boyan Silyavski]

The only way i know of, as i said above, is using flat reinforced sponge to do that. As per this sign making video:

[PaisleyPCdoctor]

I saw this video and stole a really great tip...

If you use vinyl sheet as a mask, it probably won't fray at the edges as badly as masking tape, but even so, you'll still get paint bleeding through from the edge of the lettering onto the uncarved areas. The tip in this video is to paint the letters with background colour first, let it dry, them paint carved areas. The idea is that the bleed colour would be same as background anyway. So...

With gold text carved on black background, for example...

1- paint uncarved wood black
2- apply vinyl film
3- carve out letters
4- paint letters black and allow to dry (seals bleed points)
5- paint letters gold and allow to dry.
6- remove vinyl film.
(I've never done this before- just putting the idea out there)
Here's the video I stole the bleed tip from..

https://youtu.be/NgMoYRDtrUo

[magicniner]

Boyan's link is excellent but the results the guy in the video achieved don't look 100%
I don't do brushes and foam, just good masking and spray guns, but I'm from an automotive paint background and I'm really picky about colour and surface finish, I can spot a poor job on a car at 100 yards in bad street lighting on a rainy night :D