I want to make a board displaying the weight of different things and i've searched for a long time but most of the answers seemed to assume that the part was 1 stud wide, which isn't the case with what i'm trying to do...
Is there a way to use a script to get both the mass of the part and then convert it to kilograms?
There is a way to convert that. So, 1 kilogram is 8 Roblox units of mass.
Mass counts likely as 1.25 hectograms, if you calculate 1.25 * 8, the result will be 10, which counts as a kilogram.
In grams, I would say that it is 125 grams. Calculate 125 * 8 and you get 1,000 which gives you a kilogram.