I use the spring out of an ink pen and it keeps the filler from shrinking down to begin with, and holds liquid better. I just stretched out the spring, cut it to size and twisted it counter-clockwise into the poly filling and press it into the cart, it also works if you just split the filler down the middle and then wrap it around the spring, (You can get 3 of them, out of one spring, once it's stretched out)
Last edited: