Sanding and tan resins

Sanding the full doll is fine (since the entire doll will be lightened slightly, but evenly). The majority of people, though, don't want to sand their entire doll, they only want to sand down the seams. If you do this on a tanned doll, you end up with noticeable lines between sanded and unsanded areas (which is due to the different surface texture, and happens even when the entire doll is tanned - it's not limited to dolls that are only surface tanned).

 

You are correct Tsukiyono. Ten resin is pigmented all the way through (with the exception of a few of the earliest release tan dolls from the mid 2000s). Sanding will make the resin look a little lighter at first, but if you use the right sandpaper in fine enough grits, you can restore sanded areas to their original color. I have seen certain tutorials where a polishing compound was used when sanding a dark tan doll, and she came out flawless.

 

I have returned sanded resin to an almost mirror glossy shine by first using 800, 1000, and 2000 grit papers. (I find mine in the auto section where the car paint repair stuff is) After that I use the polishing sides of a fingernail buffer (I remove the sanding sides to prevent mishaps) all over to get the super smooth surface.
I found this step to be really helpful to getting the piece to look seamless before useing MSC/ZM or a magic eraser block to make the doll look matte.
The best part is that all of the materials needed for this are easy and inexpensive to obtain.

 

I believe the one I remember was a Den of Angels thread that wasn't so much a tutorial, but more documenting the process of finishing a Twiglimbs Ylisande kit. You can try searching for it if you are a DoA member. Part of it was a video, and it was several years ago, so no guarantee that the video is still active.

 

I think there'd be the risk of having an uneven finish if you sanded the whole doll. And of course, if you just sand the seems, it'll be lighter where you sand due to the small scratches appearing lighter. I sanded a normal skin doll and the color became uneven... I sanded up to 1000 grit, but it's still uneven D: I could return the project with even finer sandpaper and polishing materials, but, ugh, I don't enjoy the process (plus I don't want my doll to be so glossy). It was a lot of work, I definitely will only be sanding white skin dolls if I have to sand anything. Just saying, sanding an entire doll is much easier said than done, especially when dealing with discoloration ^^;

 

Another thing I learned about recently to make the seam transitions sand cleaner is to use oil while sanding, it blends the color. They used cooking/mineral, and even forehead oils to test it out and they all had similar results. That said, she made sure to clean all the pieces thoroughly once she was done sanding.