Vintage Disc Grinder Restoration

This is vintage disc grinder from Hitachi Ltd Tokyo Japan. I found this grinder from the recycle shop in my city. It is 110V, 4 AMP, 50/60 Hz, 11000 RPM, Wheel Size 100. But I don't know the year of manufacture. So please share it if you know. In this videos I recorded it step by step the process of inside cleaning & outside restoration. I hope you find something useful & enjoy from this video! Credit: Gear Show - https://www.youtube.com/channel/UCWKqh_3cb6cDiz2ICWc-5Sw