You've probably seen various folks use aluminum radius corner templates in videos and they caught my eye, too. I decided to add a set to my shop and recently used them for a small master bedroom storage project I was working on. They worked well for sure, using the painter's tape and CA method for attaching them to the material. The particular set I purchased from Amazon are coded metric (which is what I use in the shop anyway) but that shouldn't cause any issues for most situations unless you are trying to fit the radius into another one that is sized differently. Regardless of what color/brand, I think these might be a good addition to many folks' bags of tricks to create consistent radius corners.
This is a link to the product I purchased; not an endorsement, but I'm pleased with the quality for the money. They seem to be out of the red ones at the moment, but do have the black, at least as of this posting.
https://www.amazon.com/gp/product/B0...e?ie=UTF8&th=1
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