Once again, I'm so confused.
My son needs to create an insert to replace a piece of glass that was in a table top. The first material we tried was 0.093" Lexan purchased from Lowe's. It's too thin. The next material was (what I think is) 1/8" hardwood plywood. It's too thick. Then, I tried a piece of hardboard. It's perfect. I thought hardboard was 1/8" thick. This piece measured 7/64", as I remember. How thick is 1/8" plywood?
The clear plastic drawers for the old Akro-Mils parts cabinets are very brittle. Are those polycarbonate or acrylic? Where to buy acrylic sheets?
When you get down to 1/4", and below, plywood thicknesses can vary a good bit as they are typically geared towards model building (particularly 1/8" and below), so you would have to measure on a case-by-case basis, though some may state their true thickness in mills if you look it up on the manufacturer's site. But, then, few plywoods are actually their stated nominal thickness in the same way that a modern 2x4 is no longer 2"x4".
The clear plastic drawers and dividers found in most parts drawers were typically
polystyrene, which is a very hard but brittle plastic, and tends to become increasingly so with age. That said, Acryllic is fairly brittle in its own right and will shatter if subjected to too much stress, such as if using an over aggressive saw blade or drilling too large a hole in one go and the bit catching as it breaks through, or if simply bent too far or impacted too hard -- not nearly as brittle as glass by any measure, but still a brittle plastic. Polycarbonate is quite the opposite by comparison as it will exhibit controlled plastic deformation if excessively stressed rather than catastrophic failure like Acryllic, which is also why it performs well as ballistic armor in appropriate thicknesses.
You can often purchase polycarbonate (Lexan) and Acryllic (Plexiglass) from places such as Lowes, Home Depot, and Ace, as well as from many online retailers. However, the selection at big box stores seems to be decreasing in recent years and some locations seem to have entirely discontinued carrying such, while the same store further down the road may still do so, subject to the whims of management.
Complicating matters, some products that state 1/8" (0.125"), for example, are really rounded to the nearest standard metric dimension, such as 3mm (0.118") or 2.5mm (0.098"), or even 2.54mm (0.10"), so it is often best to measure such directly if you need a precise thickness and can not find the actual dimensions on the manufacturer's website or literature (just take a dial caliper with you while shopping). For example, 7/64" (0.1094") is often rounded to 2.75mm (0.1083").