Centering tool
thingiverse
I believe I've seen a tool very much like this one but I decided instead of chasing my tail trying to find it I would just do a design and print of it. It's used to find the center on a piece os square material. Simply place the on the square material and rotate it one way or another until it stops and it will automaticaly show the center of the material and you can use a pencil or marker to make the center, this can be very useful for doing dowel work on wood and such. I made two sizes, one with a 3" between posts and one with 5' between posts and if someone needs a size larger to accommodate a bigger piece of square stock I could make another one. If you look a tthe images I showed how it works more or less. The way it is orientated it does not require supports. I printed this at 15% infill but if this is something you would be tossing into your tool box you might consider more infill or heck go to 100% infill to make it very strong. Files: CFL is the large one (5") and CFS1 is the smaller one (3").
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