I have considered making a aluminum bed for my 10" i3v & T6 aluminum seems to be what I have read works best for this. Maybe someone else has a better choice of materials for this. This site you can get 6061 T6 Aluminum Sheet to the size you want in increments of 1/16". I can get a 10 3/8" square by .19 thick sheet for $12.21, but shipping is another $13.61, so I would probably order 2 sheets in case I mess one up on the drilling process.

https://www.midweststeelsupply.com/s...1aluminumsheet
I was going to use this part for the belt clamp under the aluminum plate, or modify if it does not quite fit my dimensions.
http://www.thingiverse.com/thing:619347