Should Solid Surface Joints be Invisible?

With some solid surface materials, joints are highly visible because the material is "directional" or otherwise non-uniform. April 20, 2011

I just had a curved reception desk top with a beveled edge fabricated by a shop I have used for many years with success. The top is 2" thick, so there are 4 pieces in height and segmented to make it around the curve, which is about 15' long. The problem is every joint is visible. The fabricator is claiming it is because the material is directional. Material is Corian Anthracite.

Forum Responses
(Laminate and Solid Surface Forum)
From contributor H:
Seams in solid surface are not invisible and should not be sold as such. They are inconspicuous. And yes, some solid surfaces are directional. You may not be seeing the seam as much as you are seeing the change in direction of pattern.

From contributor A:
Most deck seams (top of the countertop) can be nearly invisible, but the vertical butt joints on the build up (edge of the top) aren't always perfect. Sometimes there are ghost lines, where the layers of build up are obvious. Keep in mind that if the joint is less than 3 thousandths of an inch thick, you won't see the seam. Flatness of the sheets and the amount of surface chatter when they are sanded at the factory all affect the buildup seams. And like contributor H said, some materials are indeed directional. Post a picture if you have one, but it sounds like this is a non-issue.

From contributor J:
If you look at the back of your Anthracite sample you will notice that there are very few, if any, of the sparkle particulates. Now imagine stacking four layers... every layer will have lots of particulate at the top, but very little at the bottom where it meets the next layer. With the stacked edge method, I don't think you can get around this problem, even if the pieces are prepped perfectly.

From contributor M:
A poor color choice for a radius edge. That is one of many colors that should be v-grooved for edge thickness, and you can't v-groove a radius. Even a straight buildup edge in this color is not the way to go.

From contributor L:
I haven't noticed Anthracite being directional, but there is a big variation in top to bottom distribution. On straight runs we miter fold. The only way around it on curves is to use the CNC router to machine the edge to 1/8" thick by a little deeper than the thickness of the edge. Then make a form on the router and thermoform the edges to the top shape. Works fairly well, is expensive.