Some tips from Kristen Turner.
When you upload a 3D design file to Ponoko, you can preview your design before making it. Having a preview lets you know you have uploaded the design you wanted. And you can directly share the 3D preview of your design in your Ponoko showroom.
Uploading your file will automatically generate a thumbnail preview of your design. For a slightly larger preview, click on the Photos tab and then click "add or change photos." Now click "add more photos." This makes your Main Photo a little bit bigger.
If you're satisfied, go ahead and share the design. Otherwise, you can always change your mind and go back.