Thickness of old plywood: 0.27"
New: 0.20"
26% decrease in thickness!
Density of old plywood: 0.69 grams per cubic centimeter
New: 0.31 g / cm^3
55% decrease in density!
In the substitute you can see tearout and de-lamination which reflects a much softer-feeling wood. Screw heads leave big indentations in the surface. There are also fewer plies; my quarter-inch sheet has a thin central ply and two very thick face plies. As a result, partial-thickness features result in fragile, warped parts. (The old plywood has five plies of equal thickness – see last photo).
There are already YouTube videos that address baltic birch sourcing & substitution. Is there another type of structural plywood that’s more similar in density to the "old’ plywood? Maybe pine, oak, or maple?
One easy option is to redesign parts, doubling the thickness.
#1 that isn’t Baltic Birch. That doesn’t even appear to be Indonesian Birch(known for numerous voids).
I am finding many lumber yards are using Russian Baltic Birch as a generic marketing term.
This company had some actual(Cyrillic stamped) crates of 13mm birch on the floor last week. They are primarily a MDF/particle board vendor.
McKillican American
(469) 568-2280
1536 Hutton Drive
Carrollton TX 75006
Yes, exactly. That plywood I bought recently was stamped with INDONESIA. It was also a third the price of the stuff I bought several months ago. The ‘actual’ baltic birch (five plies) actually has more voids on the edges, but that doesn’t mean much. The 1/4" Indonesian plywood only has one layer on each side so it’s easier to manufacture.
I’ll give them a call. I’m using Medex MDF to make big molds for my project.
Update:
Central Hardwoods claims to have Baltic birch plywood in various thicknesses and in both sizes.
The sales person described the Indonesian plywood as “lightweight” and mentioned that they also have Vietnamese plywood, which I tried (pictured below). It’s coarser, akin to construction grade plywood, what you would put on top of a truck bed or some concrete. I haven’t taken any measurements, but it definitely feels heavier.
My biggest complaint with both of the substitutes is that they’re laminated in a paper-thin slice of aesthetic surface veneer. Besides the obvious function it probably protects it from moisture and maybe otherwise the sheets would coalesce when you tried to stack them in a warehouse. Who knows.
Between the three options it covers quite a range. The Indonesian plywood would work well for model airplane parts, Vietnamese plywood works great for the shelf on the bottom of my work bench. Baltic birch is of course the outlier in price as well as quality.
