Light coat of Sealcoat shellac under marsh stencil ink for outdoor sign?

[Jason Evans]

So I’ve been working on an engraved exterior sign made of cherry. It was masked with Oracal 631, then engraved. I used 631 because it has good tack and the sign is very detailed with many small specks of the masking to be left in place. It stuck much better than 813, 810 and 810s. 631 works great.

I am spraying the engraving with black marsh stencil ink. The problem is bleeding under the mask. The cherry is bare wood under the 631 and so a bit of the ink on my tests bleeds under the masking. So I decided I should spray something clear in the engraving first to stop the bleeding, then spray the marsh ink. Sealcoat shellac works well, I am only doing one lightly sprayed coat diluting the sealcoat 50/50 with denatured alcohol.

Im thinking of using Cabot australian timber oil on top to protect the cherry. So finally my question is will this combination work? Will the light coat of sealcoat shellac under the marsh stencil ink be ok outside?

If not can anyone recommend a better clear coat to stop the bleeding?

[Jim Becker]

You can use the shellac for the purpose you mention. It really only needs to go in the engravings that will be colored which means it's not needed under the overall finish and if you are using a penetrating oil, you sure don't want the shellac on there.

That said, there's a reason that most signmakers no longer use wood for outdoor signs; some even painstakingly do faux finishes to give the appearance of wood on materials that are more durable and don't fade to gray in the sun and weather. I'm only mentioning this so you can set your own expectations about the need to refinish the sign periodically.

[Jason Evans]

You can use the shellac for the purpose you mention. It really only needs to go in the engravings that will be colored which means it's not needed under the overall finish and if you are using a penetrating oil, you sure don't want the shellac on there.

That said, there's a reason that most signmakers no longer use wood for outdoor signs; some even painstakingly do faux finishes to give the appearance of wood on materials that are more durable and don't fade to gray in the sun and weather. I'm only mentioning this so you can set your own expectations about the need to refinish the sign periodically.

Thanks Jim. I always appreciate your input.

My original plan was no sealcoat shellac, but the bleeding, even if a small amount, had to be remedied. Definitely only in the engravings. I was just worried about shellac being used exterior, but I’m hoping if it is just a small layer and it’s covered with marsh ink and the oil things will be ok. I will recommend that the sign be re oiled periodically.