How do you paint a sign using two different colours?

[Shane]

How do you paint a sign with engraved areas and keep it looking professional without the colours blending together? I have attached an example of sign that I'll assume is painted in two different colours.

I've tried hand painting the engraved areas but the end result is not a crisp clean edge between the colours. I've tried spraying the engraved areas and then rolling another colour over the top but this causes the roller to dip slightly into unwanted areas and also a rolled finish doesn't look anywhere near as nice as using a spray gun.

I'll be working mainly with MDF and hardwood timber. Any help would be great.

Shane.

[genek]

I AM JUST LEARNING TO MAKE SIGNS SO TAKE MY ADVISE WITH A GRAIN OF SALT.
PAINT THE LETTER FIRST.. LET DRY... THE ROLLER YOU NEED IS A SMALL ROLLER WITH A TIGHT MAT... ROLL OUT MOST OF THE PAINT ON A SCRAP OF CARD BOARD. THEN ROLL AROUND AND OVER THE LETTERS VERY CAREFULLY. GO TO http://www.precisionboard.com/ WATCH THEIR VIDEO'S ONE SHOWS A MAN PAINTING LIKE I SUGGESTED TO YOU.. AGAIN I AM JUST LEARNING... ALSO GO TO THIS SITE AND ASK THE SAME QUESTION http://www.3dsignforum.com

[Shane]

I did an experiment this afternoon. I sprayed this slab of Huon Pine with a few layers of clear coat. Once all dried, I put engraved it using the CNC. Painted the engraved areas with black paint just using a paint brush and not worrying about putting black paint on the top surface.

Once that dried I sanded off the surface and hit it with another layer of clear coat. The clear coat did the trick and stopped the paint from being absorbed into the timber.

I should be able to use this idea to protect the top surface of other signs where it is painted.

Thanks Eugene for those links. I'll check them out.

[bobmoore]

Try shellac for your clear coat. It is a little more convenient, dries quickly, and still seals well. Bob

[joe]

Uh, I don't know!

As Everyone knows I'm a shellac fiend. However it's a poor clear coat. Will not last with any kind of heat, cold or moisture. It's strong suit is as a sealer/primer.

Try one of the many selections by MinWax.

[genek]

Joe crumley what type of paint do you recommend and what brand.

[bobmoore]

Shane clearly stated that he was sanding off the top surface so the shellac was NOT a clear coat or any kind of coat at all.
Bob

[Brady Watson]

There are several ways to do this...I am not a sign maker, so take it for what it's worth.

In the past I have pre-finished the sign blank and let it cure really well - sometimes this takes a few days depending on humidity. Then cover the face of the sign blank with GerberMask Ultra II - It is not cheap, but it works pretty well. Then carve through the GMU2 and put your design into the sign. Clean it, and then paint or size the areas you want to paint or gold leaf. It holds a pretty crisp edge with little bleed as long as you use sharp tools.

The other thing that may work for you is 'Snake Oil' as Joe C. coined - rubber cement that is applied to the pre-finished blank as above, carved through and peeled off. While I haven't tried this, I have used PVA (Polyvinyl Acrylate), like they use for fiberglass mold release. It takes time to apply in several thin coats (or it will alligator) and it washes off with warm soapy water.

I've also heard of using a white potato cut in half and rubbed all over the surface of the pre-finished blank to coat it with a film of starch. A noble idea, but I have no 1st hand experience doing it.

-B

[gc3]

ask here also...http://www.3dsignforum.com/beginners...factor-is-low/

[Shane]

I would normally use shellac but have found it takes too many coats to get a thick covering on the surface. The waterborne urethane varnish I have started using goes on thicker so only one or two coats are needed to stop any excess paint penetrating the top surface. And being water based, the dry time is only an hour or two.

Also I was told that if I use shellac it has to be fully cured otherwise the metho will react with the water based paints and cause cracking issues. So even thought the shellac dries quickly, I would still be forced to wait for a day or at least several hours. So that defeats the purpose of using Shellac.

I will try another sign in the next few days but this will be MDF and have a painted surface and contrasting painted engraved section. I only sand back the vanish enough to get rid of any unwanted paint that was used in the engraved areas. Once that paint is removed, i will spray the whole sign with the varnish to finish it off.