Refilling HP#21 ink cartridge?
Has anyone had success refilling Hewlett Packard ink cartridges? I cannot find any hole in the cartridge body to refill into. I was thinking of drilling a hole just large enough to insert the tip of the syringe. Another issue is the smart chip built into the cartridge, and whether this will make the cartridge unuseable once it zeros out. Please only answers from persons familiar with this model. HP F-300 using #21 and #22 ink cartridges. Thank you.