<R9.d> states:
Legal plastic types include polycarbonate (Lexan), acetal monopolymer (Delrin), acetal copolymer (Acetron GP), POM (acetal), ABS, PEEK, PET, HDPE, LDPE, Nylon (all grades), Polypropylene, and FEP.
Does the word "include" indicate a non-exhaustive list i.e. is any plastic is allowed so long as it satisfies all the other constraints (non-shattering, no thicker than 0.070", no more than 12" x 24" total)? Would 1/16" PVC sheet be legal (it has excellent impact strength)?
Furthermore, are "filled/modified" plastic sheet products which are mostly a legal base plastic but partially additive legal, provided that they are non-shattering? For example, 30% glass filled nylon sheet or Delrin AF (Delrin filled with PTFE/Teflon).
Does the word "include" indicate a non-exhaustive list i.e. is any plastic is allowed so long as it satisfies all the other constraints
No. It is meant to indicate an exhaustive list. When feasible, we try to use verbiage like "includes, but is not limited to" to indicate a non-exhaustive list.
Would 1/16" PVC sheet be legal (it has excellent impact strength)?
No, this would not be legal.
Furthermore, are "filled/modified" plastic sheet products which are mostly a legal base plastic but partially additive legal, provided that they are non-shattering? For example, 30% glass filled nylon sheet or Delrin AF (Delrin filled with PTFE/Teflon).
We are not going to be able to provide a blanket answer that would encompass all hypothetical plastic products and variants of the listed plastic types. In general, however, the specific examples provided in this question would fall outside of the intent of this rule, as they rely on the Teams to convince an inspector that "glass filled nylon" is "technically still nylon". The "red box" in G3 then applies to this situation:
If a component’s legality cannot be easily / intuitively discerned by the Robot rules as written, then Teams should expect additional scrutiny during inspection"
