Getting 1:1 (real life) scale output from SketchUp for templates, etc…
Published by rich on Saturday, January 12, 2008 - 06:12:22 - Filed under Robots and Electronics, Other Fun Stuff
Update:
Google recently added “Scale” settings to the print dialog in the free version of SketchUp which allows for 1:1 scaled printing. Unfortunately, it’s a serious pain in the butt to keep your model from getting split into 9 different pages. Although hacky, many users may still have the best luck with the technique described below.
When I first found Google SketchUp I concluded it was the solution for all my basic CAD needs.
Then I hit a big gotcha. It’s pretty much impossible to reliably get 1:1 scale output from it (at least from the free version). For that matter, it doesn’t export to any formats that contain usable dimension data.
What’s the point of designing something if I can’t print it out on paper, glue it to a piece of aluminum and then cut it on my band saw?
Fortunately, by utilizing SketchUp’s Ruby interface - I was able to come up with a work-around.
1. Create the file C:\program files\google\google sketchup 6\plugins\72dpi.rb with the following:
def make72dpi
model = Sketchup.active_model
view = model.active_view
camera1 = view.camera
camera1.perspective=false
camera1.height = view.vpheight / 72.0
model.active_view.write_image "c:\\72dpi.jpg"
end
plugins_menu = UI.menu("Plugins")
item = plugins_menu.add_item("Make 72 DPI Image") { make72dpi }
(If you have multiple versions of SketchUp installed be sure to save the file in the right directory)
2. Restart SketchUp - you should see a new menu option - “Make 72 DPI image” under the Plugins menu.
3. Switch to the view you want to print (top, bottom, etc.)
4. Select the Camera menu and switch off “Perspective”
5. Move the model around as needed to view the portion you want printed (for best results Maximize the SketchUp window)
6. Select “Make 72 DPI image” under the Plugins menu (this will create c:\72dpi.jpg)
7. Load the file c:\72dpi.jpg into Gimp or other program you know reliably outputs in 72dpi (not all apps that mention DPI work - for instance Paint.NET -does not- work)
8. Print it!
9. Verify the dimensions are really correct using a ruler / caliper / etc…
Yes, it’s a little work - but it’s really not that bad.
Troubleshooting:
- Make sure Gimp is set to 72 DPI under the “Image / Print Size Menu”
- It’s possible your printer is actually off-scale (sometimes even only in one dimension) - try tweaking Gimps’s separate X and Y DPI settings to compensate
- Did you switch off perspective in SketchUp?
- Make sure your printer driver isn’t set to “fit to page” or otherwise scale
72 DPI Template for Melty B 2.0 Combat Robot
