[Here's] how I build movie-accurate hands of Optimus Prime: First of all I unscrewed the hands of the arms and unscrewed the thumbs. Then I cut off his hands of the base and made the base flat with a fine metal-rasp and sanding-paper (grid 400 waterproof): Next I made the hands fit on the upper-part of the Bionicle joint and I drilled the hole where I put the thumbs in a little wider to fit the thumbs in it: Then I put a screw into the upper-part of the joint to attach the thumbs. I also drilled holes in the upper hand part and the upper-part of the joint and put some metal-pins in with superglue to make a strong connection. Then I put it all together with super glue: [The] next step was to make the connection with the base. I drilled a hole in the center of the base just above the hole where you attach the base on the arms. Then I drilled a hole into the Lego pin, cut it to the right size, put a metal pin in it and glued it together on the base: Then I attached the Bionicle lower-part of the joint (that little black ball) on the base and also the hand. The hands must be removed to transform Optimus to truck-mode because the hands don’t fit in the sleeping-cabin: To make the hands movie accurate I looked at the CGI pictures to make the backside of his hands. I used sheet styrene of the brand Evergreen which can be bought at a local hobby-store. I attached it with metal-pins and superglue: Next I did the paint-job with a satin black base-coat using Revell acrylic satin black number 302. I dry-brushed the hands with Citadel Games Workshop Chainmail, and to brighten it a little up [I used] Mithrill Silver of the same brand. I also colored the finger-joints with Citadel Brazing Brass, Revell Messing and Revell Gold. All are acrylics. To fixate everything, I put two layers of outdoor satin sealer of the brand Plaid Folk Art: Thanks. It doesn't bother me that they have to be removed because I wanted them pose-able. The hole goes through the bottom but you don't see a thing because I put a little drop of superglue on the other side and used it as some sort of filler. It became rock-solid. Then, I flattened it all with a very fine metal rasp, waterproof sanding paper 400 grit, and 800 grit made [it] all smooth. Next, I painted the bottoms with Revell number 54 Midnight Blue Gloss acrylic. This color is close to the original blue color. I gave OPs his head the same color, which you can see on the WIP-update I did on September, 7th, 2008.