1.) Gaps and overlaps in the core:
There should be no gaps in the core (small spaces between the core layers). Look for them in the side profile along the length and width of a panel. It should look like the layers that run straight in parallel lines with no gaps.
Request the full core multilayer panel made with a full core and not “Fall”. Gaps from 1mm to 2mm are allowed intermittently for a couple of cases. Anything more compromises the structural integrity of the panel.
It shouldn’t have too much overlap of these layers of layers when composing. The lines of the different layers on the side profile of the plywood should be straight. If they overlap too much, that’s not good.
The heavier the canvas, the better its density, and therefore the better its strength and performance. Regular red plywood filled with eucalyptus wood should weigh 39+ kg for a 19mm 8 × 4 sheets of plywood. Alternative quality plywood made from alternating layers of eucalyptus and poplar wood should weigh approximately 32+ for a 19mm 8×4 foot sheet of plywood.
3.) Prefer eucalyptus (red core):
There is a myth that Gurjan is the finest wood we should use. It is not. It has a slightly higher density but has no tangible advantage over eucalyptus when it comes to performance, but it costs a lot more! Eucalyptus does the job and serves the purpose your veil is meant to do for a lifetime. So instead of buying a very expensive Gurjan (no longer available in-country, imported from Burma), go for the eucalyptus core.
4.) Ability to Hold Nails:
The strength of a plywood panel is based on its ability to hold onto a nail while used in furniture. Before purchasing a layer, ask your dealer to hammer a nail (1.5-inch # 14) into the side profile of a plywood sheet. If the layers break or crack during nailing, the bonding is not good enough and will not work for interiors.
5.) Test Reports:
Any genuine manufacturer would have factory lab test reports and third party test reports of their plywood panels. Ask the retailer for them before purchasing. A good manufacturer also generally offers a guarantee on the panels, ask for a certificate if they have any
6.) Choose correctly:
Finally, buy according to the purpose for which you need it. For indoor furniture, which will not come into contact with water, use the MR (moisture resistant) grade, for all furniture that has the ability to come into contact with water as often as kitchen cabinets, use BWP (boiling water resistant) / Marine Ply. You can test a marine canvas for its waterproof feature by taking a cut sample and boiling it in a pressure cooker for 7 whistles. The layers of the layer do not have to genuinely delaminate like the standard marine layer. If it splits, it’s probably not a marine layer.