[Captivate Accessories] d3v14n7:
I have a few suggestions for you that will make your dock feel more solid, make it easier to sand and paint and also won't chip. In the end, if done right, it will look like something that came out of a factory.

I use this method to fabricate and modify many things, PC cases, fixing laptop cases, building a laptop holder for my car, home/car speaker cabinets, dashboard modification, keyboards, mouse and tons of other stuff... The possibilities are endless.

Materials needed:

Small, thin pieces of wood, popsicle sticks and toothpicks work well.

Thick gauge, solid copper or aluminum wire.

Short strand fiberglass body filler. Comes in a small paint can with a tube of paste to mix it with.

Pantyhose or nylon/aluminum screen for doors and windows (optional, but will make it much easier to mold it in the shape you want and will provide a nice flat, even surface to apply the fiberglass and make it stick to the wood and wire).

Plastic card (IE: old credit card or something similar) that you won't be using anymore. DO NOT USE AN ACTIVE CREDIT CARD UNLESS YOU NEVER PLAN ON USING IT AGAIN! You have been warned.

Wood glue, hot glue, epoxy (optional)

Sandpaper low grit (80-120) for basic shaping, high grit (400+) for a smooth finish.

Metal files for shaping (optional but highly recommended)

First, build a simple frame for your dock out of thin wood or out of solid thick gauge copper/aluminum wire or a combination of both. The wire is best of you want curved surfaces, you can use both materials if you want... The difference is that you'll have to solder or epoxy the wire together to make the frame while you can just glue the wood using wood glue. Make sure you leave a few (~2-3mm) millimeters of space where your phone will sit as you will be adding the fiberglass filler everywhere on the frame to hide it and make it fit snugly.

Next, take your pantyhose or nylon/aluminum screen, wrap your dock with it and glue it in place so it doesn't move... Next mix up some of the fiberglass filler with the paste (follow directions on the can for ratio) and start applying it with a thin piece of plastic (old credit card or something similar that you will not use again), try to apply it as smooth and even as possible as it will make your life easier when it comes to sanding. Also, don't mix large batches at once as it dries fairly quickly, it's better to mix a small batch, use it all, and mix more to finish the job than to have it harden before you're able to use it all...

After you completely covered your piece in a thin layer, let it dry for about 20 mins (enough so it holds its shape), then repeat over and over again until you get the desired thickness and shape (make sure your phone still fits in the slot after drying and before you apply the next coat, if it doesn't, some sanding with the lower grit sandpaper or a metal file will be necessary)... After you're done applying the fiberglass, let your dock sit for at least 24 hours so it has enough time to cure. Then, all that's left to do is sanding it all smooth with the high grit sandpaper, primer and then paint...

This will make a dock that is fairly light, extremely durable and won't melt in the sun... Oh and depending how well you do the job, it can look like it came right out of a factory.

Also, if you don't use a case on your phone, you can just buy a cheap hard case online and build the dock around that using the same method, it would make fitting the phone MUCH easier and make it fit more snugly.

Another point, if you plan on having embedded electronics in the fiberglass, make sure you insulate it all with liquid electrical tape or something similar as it can be conductive and will mess with your circuits.

Enjoy and have fun!