A variant of the paint bottle shaker I posted. This one will shake up to two bottles of craft acrylic paint at the same time. Tested and works great.
On this one you need to place the bottles in place upside down. I didn't use any rubber bands and the bottles held in place just fine — but you may want to use bands as a precaution.
You will need to cut a saw blade to a length of 5 to 6 inches and grind or file the teeth down. There are two holes to bolt the blade in but I found it wasn't necessary. I smeared teh blade with epoxy and drove it into the slot with a hammer til it bottomed out. I've used it about 10 times to date and the blade has not slipped.
WARNING Since this does attach to a power tool use precautions.Safety glasses, point it in a bucket or at the ground. Use common sense. It's designed so the bottles won't come out but sh#t happens.
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