i think i know your problem. your going about this backwards. you are basecoating your model twice. once with black and than again with white. it should be the other way around since your are doing a predominately bright coloured scheme you need to do your steps but switch them. basecoat the models white. paint the parts that are not going to be yellow with black or whatever dark colour you need for a shade colour. than just apply the yellow you need to the white parts.uranium-238 said:only problem is, it takes forever to paint a single miniature with this scheme, since the main color i'm using for the armor is GW's golden yellow paint. over both white and black basecoats it takes several different coats to get a nice, strong, solid yellow color. right now i'm basecoating the entire model black, then re-coating anything that i'm painting golden yellow with white.
also if you are lucky enough to have a crafts store around you try the gesso aproach. (search these and forums like bolter and chainsword for more info). i have found that you can add a bit of colour to the gesso to give you pre done highlights. i was actually messing around with some white gesso and yellow paint from a company called delta ceramcoat. i was able to mix there bright yellow with the gesso and apply a nice basecoat over a plastic model. although the model was a light yellow it made for painting yellow easier.
good luck and keep us posted on how things work out for you.