Working with png files

From time to time, a “potter” friend asks me to make a stamp for marking the bottom of different projects. I have received lots of help from this forum in the past to do this. In the last correspondence, Dave R. suggested that Image Trimmer might be of use.

I now have another project. I have a skp file with various size stamp bases. Another friend has supplied two png files of the desired image.
letter base 3 sizes.skp (235.2 KB)

Here are the two images that I want to make into stamps.
MKC Stamp

Can someone walk me through the process to bring the images into Sketchup (File/Import) and then manipulate them with Image Trimmer to get geometry that I can paste onto the stamp base and then extrude to make a 3D printed stamp?

I have looked for instructional youtube videos on this but haven’t found anything yet.

Using Sketchup Make 2017, and have Image Trimmer and Image Trimmer-Simplifier available on the Tools menu…

Hi Terry. Try these steps.

Use File>Import to import the PNG into SketchUp. (I find making them quite large is a good idea.)
Save the file.
Select the image.
Start Image Trimmer and wait until it starts asking you questions. Then answer them.
The last question will be related to simplifying the geometry. The lower the value, the less simplifying you’ll get.

The edges of the resulting geometry will be hidden by default. Open the object for editing by triple clicking on it with Select. Then Right click on it and choose Unhide from near the top of the Context menu if you want to make the edges visible.

Note that at least as the forum serves up your images, they aren’t incredibly high resolution. You might find it worthwhile to just trace them with the drawing tools to better average out the pixel variations.

By the way, the first image, at least as it comes from the forum doesn’t have totally transparent pixels for the background so it needs to be edited in an image editor first. Here’s what I got from running Image Trimmer on it with simplification set to 2.0.

The pixelation along the edges due to the low res image makes a pretty rough model.

Here you can see the difference between the Image Trimmer version in the foreground and a version drawn in SketchUp using the trimmed image only as a reference.

When I start Image Trimmer, it’s busy for a couple of minutes, but there are no questions when it comes back. I was expecting questions from reading the documentation in Sketchucation so that’s when I realized I need some help.

That’s interesting. The Sketchup drawn version looks a lot cleaner. Is there a way to use the image as a template and then use the pencil tool to trace out the cleaner pattern? Well, you did it so there must be.

Did you try editing the image to make sure that the background is really transparent? Were there any messages at the bottom left of the screen?

It is because the edges aren’t following the pixels in the image.

You can do that without employing Image Trimmer at all. Import the image and make it quite large. I like to temporarily edit the style to make Profiles very thick and give them a color that will show easily over the black of the image. Then trace around the image with the various drawing tools. When you close a loop of edges you’ll get a face. I haven’t closed the loop here.


Another good use of color. I just got used to assigning a vivid green to reversed faces so I recognize them right away. And now using a bright color to trace around the image is another good use.
My tracing with straight lines is OK. Do I need to practice my mouse control to draw decent curves or is there a technique for this too?

Yes indeed.

Probably. Zooming in can help. Working huge can also help.

Sounds like you may be trying to do the curves with the freehand tool, best option is 2 point arc tool.

My Homer Simpson impression, D’oh!