I created a bed scraper that uses double sided plastic razor blades. These have not damaged/scratched my build plates and the blades are cheap, print quickly and work well for removing purge lines and stuck parts.

To install the blade you simply angle it in and then push back until it's fully seated. Align the hole in the blade to the peg on the body and push into place. It should click and be held firmly. When removing push the blade down until it disengages from the peg and then slide out. Generally it's easier to remove by sliding to the size rather than pulling straight out.

I have printed in both PETG and PLA. Both work but PETG does seem stronger.