If you’ve ever had to add rivets to a model, you’re probably aware how hard it can be to get the spacing right, especially if it’s a distance you can’t easily measure with a common ruler. Some time ago, I came up with a simple enough solution, that I now put some more time and effort into so that I can share it with the rest of you, in the hope you’ll find it useful too 
That is to say, rulers with spaces between the marks of 1.00, 1.05, 1.10, 1.15, etc. millimetres:
[ATTACH]488778[/ATTACH]
And because I was making these anyway, also an aid for evenly spacing out rivets and other things around the circumference of round objects:
[ATTACH]488777[/ATTACH]
You can download the PDF here — print it out at 100% (don’t reduce or enlarge to fit your paper size!) and read the instructions on the first page
Edit, about an hour later: Version 1.0.1, some typos fixed.

That is to say, rulers with spaces between the marks of 1.00, 1.05, 1.10, 1.15, etc. millimetres:
[ATTACH]488778[/ATTACH]
And because I was making these anyway, also an aid for evenly spacing out rivets and other things around the circumference of round objects:
[ATTACH]488777[/ATTACH]
You can download the PDF here — print it out at 100% (don’t reduce or enlarge to fit your paper size!) and read the instructions on the first page

Edit, about an hour later: Version 1.0.1, some typos fixed.
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