Rasp Pi 3b as Wirless USB Hub

Hello I recently followed this tutorial to turn a Raspberry Pi 0 into a wireless USB device that I used to send .STL files to my 3d printer wirelessly. https://www.reddit.com/r/ElegooMars/comments/jxhyi3/using_a_pi_zero_w_as_a_smart_usb_flash_drive_for/ It worked for the Pi 0 but then suddenly I kept getting error messages on the Printer due to some sort of failed communication. I then decided to try to do it with a Pi 3b. I was able to successfully create the wireless folder that I can put files into remotely but when I plug the Pi into any device via the USB port nothing is coming up. Is their something I need to do different with the Pi 3b versus the 0 in the instructions?

Have you checked the file after transferring it?

And when connecting the cable to the printer, does the printer consider it as a storage device?

Check your log with dmesg or journalctl and search for undervoltage or disconnects. And if you find errors check the log for entries before the error for a clue what has caused it.