I have designed these spacers in Fusion 360 for the Creality CR10-s that I have. I use these to space between the springs and the metal bracket of the heated bed, to increase the tension of the springs and make the knobs very solid. Often times with the generic springs you will find that they are lightweight and therefore bend lightly and might cause the knob to shift during a print. I purchased these:
springs from Amazon that worked great for me after I added these spacers. I have not had to level my CR10s since making these changes. So if you're like me and purchased those springs, you can print these spacers I made specifically to fit between the springs from Amazon and your metal bracket. Now you can save a trip to the local hardware store for washers! I also included a design for a generic size 1/8 inch x 1inch washer so if you'd like to customize how many washers you need, you can. The pictures I've included are just to give you an idea of where I placed them!
Have fun printing!