This is my take on a Gridfinity baseplate for the IKEA RÅSKOG cart. There is already one on Printables, however it has a lot of issues with fitting things correctly and tends to pop up due to how tight the tolerances can be. With this in mind, and also my desire to properly fit my Gridfinity items, I made the model you're seeing on this page.
Printing:
Print 2 left, 2 right, 10 of the pegs, and attach. Use some CA Glue as a way to hold them together. Go one at a time. The pegs aren't meant to hold it together, just act as a locator pin of sorts for a proper glue up. The pegs snap really easily.
Your make may vary, however I am more than happy to help if anyone needs any help with anything!