Insert mold polishing (noob here)

Hi,
I am a machining student and currently working on a mold project. I am at the point of using diamond paste on the mold inserts for polishing. We watched a video in class, but it has been a couple of weeks. I have 2 questions I am a bit unsure.


For each grit does a person usually stop when the finish is without streaks, or more a consistent color. The intent at the finest grit is for a mirror finish. We are to use 220, 400, 600, 800 and 1200 grits.


Should I use oil mixed in with the paste? I have found recommending of both with and without.

We can work on this part of the project at home, so I am working on it this weekend
Thanks, Brian

First thing first .. What material are you trying to polish ?
What media are you using for you 220-400-600-1200 .. did you use stone or ceramic ?

I usualy go dry stone for my 220 - 320 ... from there i fallow with wet ceramic (supra stone).. each grid i will cross path my last grid
For the finish of each stone or ceramic.. i will look how hard it is to remove the scratch of the last grid.. if its to long and hard ill go back down a grid..

Also is wave a problem ? if not i would go all the way with the supra stone :P

BTW at 1200 you will start to see urself on the part .. but i would not call it a mirror finish .. Depending on the paste you buy.. it will be indicated if you can use oil base liquid of not .. some paste can some dont !.. ask your supplier

PS on a machined part.. from 220 to 2400 paste .. i usualy take about 2-3 hrs a square inches if i cant wave..

We used a Hyprez fluid on Tupperware dies and also on our tablet punches pharmaceutical most of the work was carried out off site ,just my old memory i Imagine they have a site with useful tips.

I wet sand my molds all the way up to 2000 and then use mold polish and buffing.

As others have said, it depends what material you are working on though. My molds are carbon fiber with an epoxy based gel coat for the surface which is easy to polish. Metal molds are a different animal.