Custommaker Preview Accuracy?

I was playing with a full color brick wall model that could be used to apply an image to simulate graffiti, advertising, etc. After loading everything up I did a test and it looks like the underlying brick pattern may be getting affected, perhaps smoothed and smudged in the process. And the same smudging seems to be happening on the other side of the wall as well. Would the actual print turn out this way or is it just a preview issue? Not really wanting anyone to spend $20 to test for the results.

https://www.shapeways.com/product/USDRD5J6L

I tried a different method of wall construction and there still appears to be a change to the background pattern. But real or preview artifact, that is the question!

https://www.shapeways.com/product/5KHG6ES6H

MrNibbles, what you're seeing are accuracy limitations due to voxelization of your model. CustomMaker, which runs off of ShapeJS, uses a voxel size of 0.2 mm for the preview, so the model could potentially shift by half a voxel.

I took a look at the first model (USDRD5J6L) you linked to. The gap between bricks is about 0.25 mm, and thus it can shift by 0.125 mm in the preview. It's why some of the white lines are smaller and some are larger. With a larger gap, it would be less noticeable.

The good news is that when we save the customized model (after an order), we switch to a voxel size of 0.1 mm for better accuracy. Here are screenshots of the difference.



You can see that it's better at 0.1 mm, but even then there is still a slight difference in width (potentially 0.05 mm) between some of the white lines.

Using an higher voxel resolution would certainly improve accuracy even more, but that starts introducing possible performance issues, especially for larger sized models. We don't have any plans to do that at this moment.

You are correct, the mortar gaps are drawn at 0.01 inches, or 0.254 mm. I think the final result for the actual product with the 0.1 mm voxel size will be just fine. In real life things aren't so perfect so a little variation here and there can be a good thing!

The difference between my two examples was that in the first the bricks stick out from the mortar by about 0.05 mm, which probably can't be realized anyway. In the second example the bricks were flush with the mortar so the wall should be flat. Would you recommend flat surfaces as opposed to slightly bumpy ones?

I must say I am impressed by this new ability to personalize color prints. Very impressive!

At 0.05 mm, you will most likely not see any difference between the the two. If you want a non-flat surface, you would want the bricks to be at least 2 voxels (0.2 mm) out. Maybe 3 voxels to be safe. If you don't care about that, then I would just go for the flat surface.

You'll also have to keep in mind that FCS has limitations itself (if you're printing in that material). Our materials page suggest a 0.4 mm minimum emboss height. Also, the transition between colors is normally smudged, which means you won't see a sharp edge to the bricks. The brick color may bleed slightly into the gaps, so you might want to increase the width if you want the gaps to stand out more.

Thanks for you kind words about color customization!

I have some brick patterns already printed at half the above size and it's at the absolute limit of being able to see a hint of mortar. I'll do a test print of this scale to see what happens.

As far as requiring an embossing height for full color sandstone, why is that? In this case all I'm trying to do is change the colors on a flat surface. It's not like a mono-color material where you need a height change to see the customization. I wouldn't mind having the ability to set a zero embossing height when dealing with color prints.

And if you're feeling very ambitious how about allowing the transfer of full color images to a color print, possibly with a transparent definer option for areas in an image similar to a gif with transparency? In such a case the above product could be customized with multi-color graffiti, and other products could be customized with real images. For example a scale model painting with a white canvas for a doll house might be customized with a low resolution image of the Mona Lisa or something similar. Something to think about in your spare time.

Regarding the embossing height, I only meant that you may need the bricks to stick out that much in your design if you wanted to guarantee a non-flat brick like surface. If you don't, then go with bricks flushed with the mortar.

Full color image customization (rather than just black) is not in the immediate pipeline right now, but we have thought about it. We'll let you know more if/when that happens.

Your suggestion about zero embossing for color prints is interesting. We started CustomMaker from the standpoint of customizing models with embossed or engraved text and images. With color support, it does make sense that embossing isn't required to show the customization. Unfortunately, we do not currently support zero embossing (the customization wouldn't show). The best you can do is set it to the lowest embossing allowed. We'll certainly give it some thought though.

Thanks for the feedback!