I've been commissioned to make a Slaanesh Subjugator Titan:

Another angle:

I long ago saved this picture as inspiration - NOT my own, I wish I knew who originally posted it online!

I've purchased a model of this to use as the base:

Along with some Chaos Defiler limbs and Chaos icons.

I need help with the following...

1) What should I use as pincers? Any ideas for a good place to loot big mechanical pincers?

2) What good material can I use for sculpting that's relatively cheap, air dries, and sands smooth?

Thanks for any help or comments!