Layer Adhesion Measurement Device

thingiverse

This apparatus is intended to be used with a trigger-pull-force scale. They are probably only a couple bucks on line. The handle eats a couple meters but you only print it once. The keys are designed to use little filament (about a meter) and print in under an hour at 0.1mm layers. The apparatus is a handle with a 10.6 mm square opening. The keys are 10 mm square at the base and slide into the square hole. The keys are printed vertically, so the 0.5 mm rod is comprised of cross-sectional layers. There are 3 sets of "mountain ranges" (2 for the shorter keys), the center of which is precisely 1" increments from where the rod and square base meet. The concept is pretty simple. My pull-scale goes to about 8 lbs. The closest valley to the joint then would exert up to 8 inch-lbs on the joint. The second valley would go up to 16 inch-pounds, and the third 24 inch-lbs. The trigger-pull scale has a little marker which pulls down to the force exerted and stays there when the force is released. So all you need to do is pull down slowly until the rod snaps off and the little marker gives you a quantitative measure of layer adhesion. I have drawn up 6 labeled keys, 200C, 210C, and 200C at 0.1 mm and 0.2 mm layer-heights each. You can obviously slice them at whatever settings you want, but I have 6 gcodes sliced as they are labeled. I can print them all out and not worry about mixing them up. The 6 flavors are really just for your convenience... until you slice them, the label is the only difference between them. The idea is to get a sense of how filaments compare to eachother, and also where different filaments like to operate termperature and thickness wise. My Rambery filament, which is quite good as far as adhesion goes, broke at 3.3 inch-lbs for 0.2 mm layers, and 6.5 inch-lbs for 0.1mm layers. I don't think I'll ever need the outermost slot (the second slot is questionable too), so I've made short keys with just the two slots. MAKE SURE TO LET THE KEYS COOL ALL THE WAY DOWN BEFORE RUNING THE TEST!!!