I have little sauce bottles of about 40 milliliters (photo below). At any given instance I have about 40 such bottles which need to be shaken in an up-and-down motion so the ingredients in the bottle are thoroughly mixed. How do I automate such a thing?
I have tried to hold one of the bottles in a rather big clothesline clip with the 'ear' end of it in a hammer impact drill machine, but that provides a circular motion of the bottle instead of an up-and-down motion. Same result if I hold the top of the bottle in the drilling machine, resulting in a "concrete mixer" kind of action, thus further separating the ingredients instead of mixing them up.
I have seen a guy in a YouTube video use a sawzall, which I don't have. Even if I manage to get one, it will be very time-consuming to zip tie each bottle and shake it and then repeat the process. Could do 4 bottles at one go I suppose.
Edit : The content in the bottles is Propylene Glycol and Vegetable Glycerin