This is my attempt at lapping an old HS. It was done with 400 grit then 600 and finally 1200. After that rubbed with some bicarb toothpaste and then brasso. Things I learned: Dremmel is way too fast and not delicate enough. For large grooves its ok but for fine smoothing not ideal (you end up with wheel marks everywhere). Toothpaste works great! Patience is required. Brasso works better than expected. Be careful of the edges of your HS Cost Wet/Dry Sand paper from screwfix.com 2.79*3 1 at each grit. You get 10 pcs for that price. Cloths from sainsburys, simple dust cloths 2 for 0.97 or something like that. Brasso sainsburys about 1.60 Toothpaste something i had round the house. Hope this helps anyone who is looking to do this.